Skip to content
This repository
tree: eadce368fe
Fetching contributors…

Cannot retrieve contributors at this time

file 3051 lines (2223 sloc) 49.735 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051
#LyX 1.6.7 created this file. For more info see http://www.lyx.org/
\lyxformat 345
\begin_document
\begin_header
\textclass book
\use_default_options true
\language english
\inputencoding auto
\font_roman palatino
\font_sans helvet
\font_typewriter courier
\font_default_family default
\font_sc false
\font_osf false
\font_sf_scale 100
\font_tt_scale 100

\graphics default
\paperfontsize default
\spacing single
\use_hyperref false
\papersize default
\use_geometry false
\use_amsmath 1
\use_esint 1
\cite_engine basic
\use_bibtopic false
\paperorientation portrait
\secnumdepth 3
\tocdepth 3
\paragraph_separation indent
\defskip medskip
\quotes_language english
\papercolumns 1
\papersides 1
\paperpagestyle default
\tracking_changes false
\output_changes false
\author ""
\author ""
\end_header

\begin_body

\begin_layout Chapter
Templates in Lift
\end_layout

\begin_layout Standard
An XHTML page, being the central component of a web application, is likewise
 the central component of Lift's request processing.
 In Lift, we go a step further and utilize a flexible yet powerful templating
 engine that allows us to compose an XHTML
\begin_inset Index
status open

\begin_layout Plain Layout
XHTML
\end_layout

\end_inset

 page not only out of one or more XML
\begin_inset Index
status open

\begin_layout Plain Layout
XML
\end_layout

\end_inset

 files, but also from methods that can programmaticaly generate template
 XML.
 In this chapter we'll discuss the template XML capabilities and syntax,
 including XML tags provided by Lift that perform special template processing
 (Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:ArchTags"

\end_inset

).
 We will also cover how you can write your own View classes, Scala code
 that can programmatically generate template XML (Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Views"

\end_inset

).
 We'll finish up the chapter with some discussion on miscellaneous templating
 functionality.
\end_layout

\begin_layout Section
Template XML
\begin_inset CommandInset label
LatexCommand label
name "sec:Templates"

\end_inset


\end_layout

\begin_layout Standard
Templates
\begin_inset Index
status open

\begin_layout Plain Layout
Templates
\end_layout

\end_inset

 form the backbone of Lift's flexibility and power.
 A template is an XML document that contains Lift-specific tags, see
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:ArchTags"

\end_inset

, as well as whatever content you want returned to the user.
 
\end_layout

\begin_layout Standard
\align center
\begin_inset Box Shadowbox
position "t"
hor_pos "c"
has_inner_box 1
inner_pos "t"
use_parbox 0
width "75col%"
special "none"
height "1in"
height_special "totalheight"
status open

\begin_layout Plain Layout
A note on nomenclature: typically when people discuss
\begin_inset Quotes eld
\end_inset

templates
\begin_inset Quotes erd
\end_inset

 in books or on the mailing list they're talking about XML files.
 We'll cover programmatic generation of template XML in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Views"

\end_inset

.
\end_layout

\end_inset


\end_layout

\begin_layout Standard
Lift includes several built-in XML tags for specific actions.
 These utilize prefixed XML elements and are of the form
\family typewriter
<lift:tag_name/>
\family default
.
 Lift also allows you to define your own tags, which are called
\emph on
snippets
\emph default

\begin_inset Index
status collapsed

\begin_layout Plain Layout
snippets
\end_layout

\end_inset

 (Chapter
\begin_inset CommandInset ref
LatexCommand ref
reference "cha:Snippets"

\end_inset

).
 These user-defined tags are linked to Scala methods and these methods can
 process the XML contents of the snippet tag, or can generate their own
 content from scratch.
 A simple template is shown in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Sample-template"

\end_inset

.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
A Sample Template
\begin_inset CommandInset label
LatexCommand label
name "lst:Sample-template"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:surround with="default" at="content">
\end_layout

\begin_layout Plain Layout

  <head><title>Hello!</title></head>
\end_layout

\begin_layout Plain Layout

  <lift:Hello.world />
\end_layout

\begin_layout Plain Layout

</lift:surround>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
Notice the tags that are of the form
\family typewriter
<lift:name>
\family default
 which in this case are
\family typewriter
<lift:surround>
\family default
 and
\family typewriter
<lift:snippet>.
 
\family default
These are two examples of Lift-specific tags.
 We'll discuss all of the tags that users will use in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:ArchTags"

\end_inset

, but let's briefly discuss the two shown here.
 We use the built-in
\family typewriter
<lift:surround>
\begin_inset Index
status open

\begin_layout Plain Layout
lift:surround
\end_layout

\end_inset


\family default
 tag (Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sub:surround-tag"

\end_inset

) to make Lift embed our current template inside the
\begin_inset Quotes eld
\end_inset

default
\begin_inset Quotes erd
\end_inset

 template.
 We also use
\family typewriter
<lift:snippet>
\family default
 tag (aliased to Hello.world) to execute a snippet that we defined.
 In this instance, we execute the method
\family typewriter
world
\family default
 in the class
\family typewriter
Hello
\family default
to generate some content.
\end_layout

\begin_layout Subsection
Locating Template XML
\end_layout

\begin_layout Standard
During request processing, Lift first tries to match against the
\family typewriter
LiftRules.viewDispatch
\begin_inset Index
status open

\begin_layout Plain Layout
viewDispatch
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Views ! Explicit dispatch
\end_layout

\end_inset


\family default
 function to see if an explicit View method is defined for the request.
 If there isn't a
\family typewriter
viewDispatch
\family default
 match, then Lift next tries to locate a file in the template directory
 tree (typically in a WAR archive) that matches the request.
 Lift tries several suffixes (html, xhtml, htm, and no suffix) and also
 tries to match based on the client's
\family typewriter
Accept-Language
\family default
 header.
 The pattern Lift uses is:
\end_layout

\begin_layout LyX-Code
<path to template>[_<language tag>][.<suffix>]
\end_layout

\begin_layout Standard
Because Lift will implicitly search for suffixes, it's best to leave the
 suffix off of your links within the web app.
 If you have a link with an href of
\family typewriter
/test/template.xhtml
\family default
, it will only match that file, but if you use
\family typewriter
/test/template
\family default
 for the href and you have the following templates in your web app:
\end_layout

\begin_layout Itemize

\family typewriter
/test/template.xhtml
\end_layout

\begin_layout Itemize

\family typewriter
/test/template_es_ES.xhtml (Spanish localized for Spain)
\end_layout

\begin_layout Itemize

\family typewriter
/test/template_ja.xhtml
\end_layout

\begin_layout Standard
then Lift will use the appropriate template based on the user's requested
 language if a corresponding template is available.
 For more information regarding internationalization please see Appendix
 
\begin_inset CommandInset ref
LatexCommand ref
reference "cha:Internationalization"

\end_inset

.
 In addition to normal templates, your application can make use of hidden
 templates
\begin_inset Index
status open

\begin_layout Plain Layout
hidden templates
\end_layout

\end_inset

.
 These are templates that are located under the
\family typewriter
/templates-hidden
\family default
 directory of your web app.
 Technically, Lift hides files in any directory ending in
\begin_inset Quotes eld
\end_inset

-hidden
\begin_inset Quotes erd
\end_inset

, but templates-hidden is somewhat of a de facto standard.
 Like the
\family typewriter
WEB-XML
\family default
 directory, the contents cannot be directly requested by clients.
 They can, however, be used by other templates through mechanisms such as
 the
\family typewriter
<lift:surround>
\family default
 and
\family typewriter
<lift:embed>
\family default
 tags (Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sub:embed-tag"

\end_inset

).
 If a static file can't be located then Lift will attempt to locate a View
 class (Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Views"

\end_inset

) that will process the request.
 If Lift cannot locate an appropriate template based on the request path
 then it will return a 404 to the user.
\end_layout

\begin_layout Subsection
Processing Template XML
\end_layout

\begin_layout Standard
Once Lift has located the correct template, the next step is to process
 the contents.
 It is important to understand that Lift processes XML tags recursively,
 from the outermost tag to the innermost tag.
 That means that in our example Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Sample-template"

\end_inset

, the surround tag gets processed first.
 In this case the surround loads the default template and embeds our content
 at the appropriate location.
 The next tag to be processed is the
\family typewriter
<lift:Hello.world/>
\family default
 snippet.
 This tag is essentially an alias for the lift:snippet tag (specifically,
 
\family typewriter
<lift:snippet type=
\begin_inset Quotes eld
\end_inset

Hello:world
\begin_inset Quotes erd
\end_inset

>
\family default
) , and will locate the Hello class and execute the world method on it.
 If you omit the
\begin_inset Quotes eld
\end_inset

method
\begin_inset Quotes erd
\end_inset

 part of the type and only specify the class (
\family typewriter
<lift:Hello>
\family default
 or
\family typewriter
<lift:snippet type=
\begin_inset Quotes eld
\end_inset

Hello
\begin_inset Quotes erd
\end_inset

>
\family default
), then Lift will attempt to call the
\family typewriter
render
\family default
 method of the class.
\end_layout

\begin_layout Standard
To give a more complex example that illustrates the order of tag processing,
 consider Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:A-Recursive-Tag"

\end_inset

.
 In this example we have several nested snippet tags, starting with
\family typewriter
<A.snippet />
\family default
.
 Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Recursive-Tag-Snippets"

\end_inset

 shows the backing code for this example.
 Snippets are covered in more detail in Chapter
\begin_inset CommandInset ref
LatexCommand ref
reference "cha:Snippets"

\end_inset

.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
A Recursive Tag Processing Example
\begin_inset CommandInset label
LatexCommand label
name "lst:A-Recursive-Tag"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:A.snippet>
\end_layout

\begin_layout Plain Layout

  <p>Hello, <A:name />!</p>
\end_layout

\begin_layout Plain Layout

  <p>
\end_layout

\begin_layout Plain Layout

    <lift:B.snippet>
\end_layout

\begin_layout Plain Layout

      <B:title />
\end_layout

\begin_layout Plain Layout

      <lift:C.snippet />
\end_layout

\begin_layout Plain Layout

    </lift:B.snippet>
\end_layout

\begin_layout Plain Layout

  </p>
\end_layout

\begin_layout Plain Layout

</lift:A.snippet>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
The first thing that happens is that the contents of the
\family typewriter
<lift:A.snippet>
\family default
 tag are passed as a
\family typewriter
NodeSeq
\family default
 argument to the
\family typewriter
A.snippet
\family default
 method.
 In the
\family typewriter
A.snippet
\family default
 method we bind
\begin_inset Index
status open

\begin_layout Plain Layout
bind
\end_layout

\end_inset

, or replace, the
\family typewriter
<A:name />
\family default
 tag with an XML Text node of
\begin_inset Quotes eld
\end_inset

The A snippet
\begin_inset Quotes erd
\end_inset

.
 The rest of the input is left as-is and is returned to Lift for more processing.
 Lift examines the returned
\family typewriter
NodeSeq
\family default
 for more lift tags and finds the
\family typewriter
<lift:B.snippet>
\family default
 tag.
 The contents of the
\family typewriter
<lift:B.snippet>
\family default
 tag are passed as a
\family typewriter
NodeSeq
\family default
 argument to the
\family typewriter
B.snippet
\family default
 method, where the
\family typewriter
<B.title />
\family default
 tag is bound with the XML Text node
\begin_inset Quotes eld
\end_inset

The B snippet
\begin_inset Quotes erd
\end_inset

.
 The rest of the contents are left unchanged and the transformed
\family typewriter
NodeSeq
\family default
 is returned to Lift, which scans for and finds the
\family typewriter
<lift:C.snippet />
\family default
 tag.
 Since there are no child elements for the
\family typewriter
<lift:C.snippet />
\family default
 tag, the
\family typewriter
C.snippet
\family default
 method is invoked with an empty
\family typewriter
NodeSeq
\family default
 and the
\family typewriter
C.snippet
\family default
 returns the Text node
\begin_inset Quotes eld
\end_inset

The C snippet
\begin_inset Quotes erd
\end_inset

.
\end_layout

\begin_layout Standard
\begin_inset listings
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
The Recursive Tag Snippets Code
\begin_inset CommandInset label
LatexCommand label
name "lst:Recursive-Tag-Snippets"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

...
 standard Lift imports ...
\end_layout

\begin_layout Plain Layout

class A {
\end_layout

\begin_layout Plain Layout

  def snippet (xhtml : NodeSeq) : NodeSeq =
\end_layout

\begin_layout Plain Layout

    bind("A", xhtml, "name" -> Text("The A snippet"))
\end_layout

\begin_layout Plain Layout

}
\end_layout

\begin_layout Plain Layout

class B {
\end_layout

\begin_layout Plain Layout

  def snippet (xhtml : NodeSeq) : NodeSeq =
\end_layout

\begin_layout Plain Layout

    bind("B", xhtml, "title" -> Text("The B snippet"))
\end_layout

\begin_layout Plain Layout

}
\end_layout

\begin_layout Plain Layout

class C {
\end_layout

\begin_layout Plain Layout

  def snippet (xhtml : NodeSeq) : NodeSeq = Text("The C snippet")
\end_layout

\begin_layout Plain Layout

}
\end_layout

\end_inset


\end_layout

\begin_layout Standard
While the contents of the
\family typewriter
A.snippet
\family default
 tag are passed to the
\family typewriter
A.snippet
\family default
 method, there's no requirement that the contents are actually used.
 For example, consider what would happen if we swapped the B and C snippet
 tags in our template, as shown in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:The-Swapped-Recursive"

\end_inset

.
 In this example, the
\family typewriter
C.snippet
\family default
 method is called before the
\family typewriter
B.snippet
\family default
 method.
 Since our
\family typewriter
C.snippet
\family default
 method returns straight XML that doesn't contain the B snippet tag, the
 B snippet will never be executed! We'll cover how the
\family typewriter
eager_eval
\family default
 tag attribute can be used to reverse this behavior in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sub:Eager-Eval"

\end_inset

.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
The Swapped Recursive Snippet Template
\begin_inset CommandInset label
LatexCommand label
name "lst:The-Swapped-Recursive"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:A.snippet>
\end_layout

\begin_layout Plain Layout

  <p>Hello, <A:name />!</p>
\end_layout

\begin_layout Plain Layout

  <p>
\end_layout

\begin_layout Plain Layout

    <lift:C.snippet>
\end_layout

\begin_layout Plain Layout

      <lift:B.snippet>
\end_layout

\begin_layout Plain Layout

        <B:title />
\end_layout

\begin_layout Plain Layout

      </lift:B.snippet>
\end_layout

\begin_layout Plain Layout

    </lift:C.snippet>
\end_layout

\begin_layout Plain Layout

  </p>
\end_layout

\begin_layout Plain Layout

</lift:A.snippet>
\end_layout

\begin_layout Plain Layout

<!-- After the A and C snippets have been processed: -->
\end_layout

\begin_layout Plain Layout

<p>Hello, The A snippet</p>
\end_layout

\begin_layout Plain Layout

<p>The C snippet</p>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
As you can see, templates are a nice way of setting up your layout and then
 writing a few methods to fill in the XML fragments that make up your web
 applications.
 They provide a simple way to generate a uniform look for your site, particularl
y if you assemble your templates using the surround and embed tags.
 If you'd like programmatic control over the template XML used for a particular
 request, you'll want to use a View, which is discussed in the next section.
\end_layout

\begin_layout Section
Views
\begin_inset CommandInset label
LatexCommand label
name "sec:Views"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Views
\end_layout

\end_inset


\end_layout

\begin_layout Standard
We just discussed Templates and saw that through a combination of an XML
 file, Lift tags, and Scala code we can respond to requests made by a user.
 You can also generate an XHTML response entirely in code using a View.
 Custom dispatch is a similar method which can be used to programmatically
 return any kind of response (not just XHTML), and is covered in more depth
 in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Custom-dispatch-func"

\end_inset

.
\end_layout

\begin_layout Standard
A view function is a normal Scala method of type
\begin_inset Formula $()\Rightarrow scala.xml.NodeSeq$
\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
NodeSeq
\end_layout

\end_inset

.
 The
\family typewriter
NodeSeq
\family default
 that's returned from a view is processed for template tags in the same
 way that XML loaded from a static file would be.
 As we showed in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:The-Rendering-Process"

\end_inset

, there are two ways that a View can be invoked.
 The first is by defining a partial function for
\family typewriter
LiftRules.viewDispatch
\begin_inset Index
status open

\begin_layout Plain Layout
viewDispatch
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Views ! Explicit dispatch
\end_layout

\end_inset


\family default
, which allows you to dispatch to any statically-available method (i.e.
 on an
\family typewriter
object
\family default
, not a
\family typewriter
class
\family default
), or to a
\family typewriter
LiftView
\family default
 (explained in a moment) object for any arbitrary request path.
 The second way that a View can be invoked is by reflection: if the first
 element of the request path matches the class name of the View (as defined
 in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sub:Class-Resolution"

\end_inset

), then the second element is used to look up the View function depending
 on which trait the View class implements.
 For performance reasons, explicit dispatch via
\family typewriter
LiftRules.viewDispatch
\family default
 is recommended because reflection incurs a significant cost for each request.
 When you use
\family typewriter
LiftRules.viewDispatch
\family default
, you need to provide an instance of
\family typewriter
scala.lang.Either
\family default
 to differentiate the dispatch type: a
\family typewriter
scala.lang.Left
\family default
 indicates a method returning a
\family typewriter
Box[NodeSeq]
\family default
, while a
\family typewriter
scala.lang.Right
\family default
 indicates a
\family typewriter
LiftView
\family default
 object.
 If you want to dispatch a request to a
\family typewriter
LiftView
\family default
 object, the match in the
\family typewriter
LiftRules.viewDispatch
\family default
 is made on all path components except the last one (e.g.
 
\family typewriter
List.init
\family default
), and that object's
\family typewriter
dispatch
\family default
 method is checked against the last component of the path to further determine
 which method on the object will handle the request.
 Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Explicit-View-Dispatch"

\end_inset

 shows how we can define an RSS view as a feed using explicit dispatch.
 Note that we use extraction on the requested path in this case to provide
 account-specific feeds and a security token to prevent feed browsing.
\end_layout

\begin_layout Standard
\begin_inset listings
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
Explicit View Dispatch
\begin_inset CommandInset label
LatexCommand label
name "lst:Explicit-View-Dispatch"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

// In Boot.boot:
\end_layout

\begin_layout Plain Layout

LiftRules.viewDispatch.append {
\end_layout

\begin_layout Plain Layout

  // This is an explicit dispatch to a particular method based on the path
\end_layout

\begin_layout Plain Layout

  case List("Expenses", "recent", acctId, authToken) =>
\end_layout

\begin_layout Plain Layout

    Left(() => Full(RSSView.recent(acctId, authToken)))
\end_layout

\begin_layout Plain Layout

\end_layout

\begin_layout Plain Layout

  // This is a dispatch via the same LiftView object.
 The path
\end_layout

\begin_layout Plain Layout

  // "/Site/news" will match this dispatch because of our dispatch
\end_layout

\begin_layout Plain Layout

  // method defined in RSSView.
 The path "/Site/stuff/news" will not
\end_layout

\begin_layout Plain Layout

  // match because the dispatch will be attempted on List("Site","stuff")
\end_layout

\begin_layout Plain Layout

  case List("Site") => Right(RSSView)
\end_layout

\begin_layout Plain Layout

}
\end_layout

\begin_layout Plain Layout

\end_layout

\begin_layout Plain Layout

// Define the View object:
\end_layout

\begin_layout Plain Layout

object RSSView extends LiftView {
\end_layout

\begin_layout Plain Layout

  def dispatch = {
\end_layout

\begin_layout Plain Layout

    case "news" => siteNews
\end_layout

\begin_layout Plain Layout

  }
\end_layout

\begin_layout Plain Layout

\end_layout

\begin_layout Plain Layout

  def recent(acctId : String, authToken : String)() : NodeSeq = {
\end_layout

\begin_layout Plain Layout

     // User auth, account retrieval here
\end_layout

\begin_layout Plain Layout

     ...
\end_layout

\begin_layout Plain Layout

     <lift:surround with="rss" at="content">
\end_layout

\begin_layout Plain Layout

       ...
\end_layout

\begin_layout Plain Layout

     </lift:surround>
\end_layout

\begin_layout Plain Layout

  }
\end_layout

\begin_layout Plain Layout

\end_layout

\begin_layout Plain Layout

  // Display a general RSS feed for the entire site
\end_layout

\begin_layout Plain Layout

  def siteNews() : NodeSeq = { ...
 }
\end_layout

\begin_layout Plain Layout

}
\end_layout

\end_inset


\end_layout

\begin_layout Standard
If you want to use reflection for dispatch
\begin_inset Index
status open

\begin_layout Plain Layout
Views ! Implicit dispatch
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Views ! Reflection dispatch
\end_layout

\end_inset

 then there are two traits that you can use when implementing a view class:
 one is the
\family typewriter
LiftView
\family default

\begin_inset Index
status collapsed

\begin_layout Plain Layout
LiftView
\end_layout

\end_inset

 trait, the other is the
\family typewriter
InsecureLiftView
\family default

\begin_inset Index
status collapsed

\begin_layout Plain Layout
InsecureLiftView
\end_layout

\end_inset

 trait, both under the
\family typewriter
net.liftweb.http
\family default
 package.
 As you may be able to tell from the names, we would prefer that you extend
 the
\family typewriter
LiftView
\family default
 trait.
 The
\family typewriter
InsecureLiftView
\family default
 determines method dispatch by turning a request path into a class and method
 name.
 For example, if we have a path
\family typewriter
/MyStuff/enumerate
\family default
, then Lift will look for a class called
\family typewriter
MyStuff
\family default
 in the view subpackage (class resolution is covered in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sub:Class-Resolution"

\end_inset

) and if it finds
\family typewriter
MyStuff
\family default
 and it has a method called
\family typewriter
enumerate
\family default
, then Lift will execute the
\family typewriter
enumerate
\family default
 method and return its result to the user.
 The main concern here is that Lift uses reflection
\begin_inset Index
status collapsed

\begin_layout Plain Layout
reflection
\end_layout

\end_inset

 to get the method with
\family typewriter
InsecureLiftView
\family default
, so it can access any method in the class, even ones that you don't intend
 to make public.
 A better way to invoke a View is to extend the
\family typewriter
LiftView
\family default
 trait, which defines a dispatch partial function.
 This dispatch function maps a string (the
\begin_inset Quotes eld
\end_inset

method name
\begin_inset Quotes erd
\end_inset

) to a function that will return a
\family typewriter
NodeSeq
\family default
.
 Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Dispatch-in-LiftView"

\end_inset

 shows a custom
\family typewriter
LiftView
\family default
 class where the path
\family typewriter
/ExpenseView/enumerate
\family default
 will map to the
\family typewriter
ExpenseView.doEnumerate
\family default
 method.
 If a user attempts to go to
\family typewriter
/ExpenseView/privateMethod
\family default
 they'll get a 404 because
\family typewriter
privateMethod
\family default
 is not defined in the dispatch method.
 If, however, our
\family typewriter
ExpenseView
\family default
 class implemented the
\family typewriter
InsecureLiftView
\family default
 trait and someone visited
\family typewriter
/ExpenseView/privateMethod
\family default
, we would lose our hard drive (on Unix at least).
\end_layout

\begin_layout Standard
\begin_inset listings
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
\begin_inset Note Note
status open

\begin_layout Plain Layout
Change this to be the RSS feed
\end_layout

\end_inset

Dispatch in LiftView
\begin_inset CommandInset label
LatexCommand label
name "lst:Dispatch-in-LiftView"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

class ExpenseView extends LiftView {
\end_layout

\begin_layout Plain Layout

  override def dispatch = {
\end_layout

\begin_layout Plain Layout

    case "enumerate" => doEnumerate _
\end_layout

\begin_layout Plain Layout

  }
\end_layout

\begin_layout Plain Layout

\end_layout

\begin_layout Plain Layout

  def doEnumerate () : NodeSeq = {
\end_layout

\begin_layout Plain Layout

    ...
\end_layout

\begin_layout Plain Layout

    <lift:surround with="default" at="content">
\end_layout

\begin_layout Plain Layout

     { expenseItems.toTable }
\end_layout

\begin_layout Plain Layout

    </lift:surround>
\end_layout

\begin_layout Plain Layout

  }
\end_layout

\begin_layout Plain Layout

\end_layout

\begin_layout Plain Layout

  def privateMethod () : NodeSeq = {
\end_layout

\begin_layout Plain Layout

    Runtime.getRuntime.exec("rm -rf /")
\end_layout

\begin_layout Plain Layout

  }
\end_layout

\begin_layout Plain Layout

}
\end_layout

\end_inset


\end_layout

\begin_layout Standard
A major difference between Views and other programmatic rendering approaches
 (such as Custom Dispatch) is that the
\family typewriter
NodeSeq
\family default
 returned from the View method is processed for template tags including
 
\family typewriter
surrounds
\family default
 and
\family typewriter
includes
\family default
, just as it would be for a snippet.
 That means that you can use the full power of the templating system from
 within your View, as shown in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Dispatch-in-LiftView"

\end_inset

's
\family typewriter
doEnumerate
\family default
 method.
\end_layout

\begin_layout Standard
Since you can choose not to include any of the pre-defined template XHTML,
 you can easily generate any XML-based content, such as Atom or RSS feeds,
 using a View.
\end_layout

\begin_layout Section
Tags
\begin_inset CommandInset label
LatexCommand label
name "sec:ArchTags"

\end_inset


\end_layout

\begin_layout Standard
In the earlier sections on Templates and Views we briefly touched on some
 of Lift's built-in tags, namely,
\family typewriter
<lift:snippet/>
\family default
 and
\family typewriter
<lift:surround
\family default
/>.
 In this section we'll go into more detail on those tags as well as cover
 the rest of Lift's tags.
\end_layout

\begin_layout Subsection
a
\begin_inset CommandInset label
LatexCommand label
name "sub:a-tag"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! a
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
SHtml ! a
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
AJAX ! anchor tag
\end_layout

\end_inset


\end_layout

\begin_layout Standard
The
\family typewriter
<lift:a/>
\family default
 tag is used internally by
\family typewriter
SHtml.a
\family default
 to create an anchor tag that will call an AJAX function when clicked.
 This tag is generally not used directly by developers.
 See Section
\begin_inset CommandInset ref
LatexCommand vref
reference "sub:AJAX-Generators-in-detail"

\end_inset

 for more details.
\end_layout

\begin_layout Subsection
bind
\begin_inset CommandInset label
LatexCommand label
name "sub:bind-tag"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! bind
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
binding
\end_layout

\end_inset


\end_layout

\begin_layout LyX-Code
Usage: <lift:bind name=
\begin_inset Quotes erd
\end_inset

binding_name
\begin_inset Quotes erd
\end_inset

 />
\end_layout

\begin_layout Standard
The
\family typewriter
<lift:bind/>
\family default
 tag is used as a placeholder for insertion of content within included templates
 when using the
\family typewriter
<lift:surround/> and
\family default
 
\family typewriter
<lift:embed/>
\family default
 tags.
 See Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Binding"

\end_inset

 for examples and discussion.
\end_layout

\begin_layout Subsection
bind-at
\begin_inset CommandInset label
LatexCommand label
name "sub:bind-at-tag"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! bind-at
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
binding
\end_layout

\end_inset


\end_layout

\begin_layout LyX-Code
Usage: <lift:bind-at name=
\begin_inset Quotes erd
\end_inset

binding_name
\begin_inset Quotes erd
\end_inset

>contents</lift:bind-at>
\end_layout

\begin_layout Standard
The
\family typewriter
<lift:bind-at/>
\family default
 tag is used to replace named
\family typewriter
<lift:bind/>
\family default
 tags within
\family typewriter
<lift:surround/>
\family default
 and
\family typewriter
<lift:embed/>
\family default
 tags.
 See Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sec:Binding"

\end_inset

 for examples and discussion.
\end_layout

\begin_layout Subsection
children
\begin_inset CommandInset label
LatexCommand label
name "sub:children-tag"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! children
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
children
\end_layout

\end_inset


\end_layout

\begin_layout LyX-Code
Usage: <lift:children>...multiple xml nodes here...</lift:children>
\end_layout

\begin_layout Standard
The purpose of the
\family typewriter
<lift:children/>
\family default
 tag is to allow you to create fragment templates with more than one root
 element that still parse as valid XML.
 For example, Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:A-Non-Conforming-XML"

\end_inset

 shows a template that we might want to embed into other templates.
 The problem is that XML requires a single root element, and in this case
 we have two.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
A Non-Conforming XML Fragment
\begin_inset CommandInset label
LatexCommand label
name "lst:A-Non-Conforming-XML"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<div>First Div</div>
\end_layout

\begin_layout Plain Layout

<div>Second Div</div>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
By using the
\family typewriter
<lift:children/>
\family default
 tag, as shown in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:A-Conforming-XML"

\end_inset

, we have a valid XML file.
 Lift essentially replaces the
\family typewriter
<lift:children/>
\family default
 tag with its contents.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
A Conforming XML Fragment
\begin_inset CommandInset label
LatexCommand label
name "lst:A-Conforming-XML"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:children>
\end_layout

\begin_layout Plain Layout

<div>First Div</div>
\end_layout

\begin_layout Plain Layout

<div>Second Div</div>
\end_layout

\begin_layout Plain Layout

</lift:children>
\end_layout

\end_inset


\end_layout

\begin_layout Subsection
comet
\begin_inset CommandInset label
LatexCommand label
name "sub:comet-tag"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! comet
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Comet
\end_layout

\end_inset


\end_layout

\begin_layout LyX-Code

\family typewriter
Usage: <lift:comet type="ClassName" name=
\begin_inset Quotes erd
\end_inset

optional
\begin_inset Quotes erd
\end_inset

/>
\end_layout

\begin_layout Standard
The
\family typewriter
<lift:comet/>
\family default
 tag embeds a Comet actor into your page.
 The class of the Comet actor is specified by the
\family typewriter
type
\family default
 attribute.
 The
\family typewriter
name
\family default
 attribute tells Lift to create a unique instance of the Comet actor; for
 example, you could have one Comet actor for site updates and another for
 admin messages.
 The contents of the tag are used by the Comet actor to bind a response.
 Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Ledger-Entry-Comet"

\end_inset

 shows an example of a Comet binding that displays expense entries as they're
 added.
 Comet is covered in more detail in Chapter
\begin_inset CommandInset ref
LatexCommand ref
reference "cha:AJAX-and-COMET"

\end_inset

.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
Account Entry Comet
\begin_inset CommandInset label
LatexCommand label
name "lst:Ledger-Entry-Comet"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<div class="accountUpdates">
\end_layout

\begin_layout Plain Layout

  <lift:comet type="AccountMonitor">
\end_layout

\begin_layout Plain Layout

    <ul><account:entries>
\end_layout

\begin_layout Plain Layout

      <li><entry:time/> : <entry:user /> : <entry:amount /></li>
\end_layout

\begin_layout Plain Layout

    </account:entries></ul>
\end_layout

\begin_layout Plain Layout

  </lift:comet>
\end_layout

\begin_layout Plain Layout

</div>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
As we mention in the
\family typewriter
embed
\family default
 tag documentation, mixing Comet with AJAX responses can be a bit tricky
 due to the embedded JavaScript that Comet uses.
\end_layout

\begin_layout Subsection
CSS
\begin_inset CommandInset label
LatexCommand label
name "sub:CSS-tag"

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! CSS
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
CSS
\end_layout

\end_inset


\end_layout

\begin_layout LyX-Code
Usage: <lift:CSS.blueprint />
\end_layout

\begin_layout LyX-Code
       <lift:CSS.fancyType />
\end_layout

\begin_layout Standard
The
\family typewriter
<lift:CSS/>
\family default
 tag is used to insert either the blueprint
\begin_inset Foot
status open

\begin_layout Plain Layout
\begin_inset Flex URL
status open

\begin_layout Plain Layout

http://www.blueprintcss.org/
\end_layout

\end_inset


\end_layout

\end_inset

 or fancy
\end_layout

\begin_layout Subsection
embed
\begin_inset Index
status open

\begin_layout Plain Layout
embed
\end_layout

\end_inset


\begin_inset CommandInset label
LatexCommand label
name "sub:embed-tag"

\end_inset

 
\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! embed
\end_layout

\end_inset


\end_layout

\begin_layout LyX-Code
Usage:
\family typewriter
 <lift:embed what="template_name" />
\end_layout

\begin_layout Standard
The
\family typewriter
embed
\family default
 tag allows you to embed a template within another template.
 This can be used to assemble your pages from multiple smaller templates,
 and it also allows you to access templates from JavaScript commands (Chapter
 
\begin_inset CommandInset ref
LatexCommand ref
reference "cha:Lift-and-Javascript"

\end_inset

).
 As with the
\family typewriter
surround
\family default
 tag, the template name can be either the base filename or a fully-qualified
 path.
\end_layout

\begin_layout Standard
\align center
\begin_inset Box Shadowbox
position "t"
hor_pos "c"
has_inner_box 1
inner_pos "t"
use_parbox 0
width "75col%"
special "none"
height "1in"
height_special "totalheight"
status open

\begin_layout Plain Layout

\size small
Note that if you use the embed tag to access templates from within a JsCmd
 (typically an AJAX call), any JavaScript in the embedded template won't
 be executed.
 This includes, but is not limited to, Comet widgets.
\end_layout

\end_inset


\end_layout

\begin_layout Subsection
form
\end_layout

\begin_layout Subsection
HTML5
\end_layout

\begin_layout Subsection
ignore
\end_layout

\begin_layout Subsection
lazy-load
\end_layout

\begin_layout Standard
\begin_inset Note Note
status open

\begin_layout Plain Layout
Cover
\begin_inset Quotes eld
\end_inset

template
\begin_inset Quotes erd
\end_inset

 attribute
\end_layout

\end_inset


\end_layout

\begin_layout Subsection
loc
\end_layout

\begin_layout Subsection
Menu
\end_layout

\begin_layout Subsection
Msgs
\end_layout

\begin_layout Subsection
SkipDocType
\end_layout

\begin_layout Subsection
snippet
\end_layout

\begin_layout Standard
The snippet tag is covered in detail in Section
\begin_inset CommandInset ref
LatexCommand vref
reference "sec:The-Snippet-Tag"

\end_inset

, part of the chapter on snippets.
\end_layout

\begin_layout Subsection
surround
\begin_inset Index
status open

\begin_layout Plain Layout
surround
\end_layout

\end_inset


\begin_inset Index
status open

\begin_layout Plain Layout
Tags ! surround
\end_layout

\end_inset


\begin_inset CommandInset label
LatexCommand label
name "sub:surround-tag"

\end_inset


\end_layout

\begin_layout LyX-Code
Usage:
\family typewriter
 <lift:surround with="template_name" at=
\begin_inset Quotes erd
\end_inset

binding
\begin_inset Quotes erd
\end_inset

>
\end_layout

\begin_layout LyX-Code

\family typewriter
         children
\end_layout

\begin_layout LyX-Code

\family typewriter
       </lift:surround>
\end_layout

\begin_layout Standard
The
\family typewriter
surround
\family default
 tag surrounds the child nodes with the named template.
 The child nodes are inserted into the named template at the binding point
 specified by the
\family typewriter
at
\family default
 parameter (we'll cover the bind tag in Section
\begin_inset CommandInset ref
LatexCommand ref
reference "sub:bind-tag"

\end_inset

).
 Typically, templates that will be used to surround other templates are
 incomplete by themselves, so we usually store them in the
\family typewriter
<app
\begin_inset space ~
\end_inset

root>/templates-hidden
\family default
 subdirectory so that they can't be accessed directly.
 Having said that,
\begin_inset Quotes eld
\end_inset

incomplete
\begin_inset Quotes erd
\end_inset

 templates may be placed in any directory that templates would normally
 go in.
 The most common usage of
\family typewriter
surround
\family default
 is to permit you to use a
\begin_inset Quotes eld
\end_inset

master
\begin_inset Quotes erd
\end_inset

 template for your site CSS, menu, etc.
 An example use of
\family typewriter
surround
\family default
 is shown in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Surrounding-your-page"

\end_inset

.
 We'll show the counterpart master template in the section on the bind tag.
 Note also that the surrounding template name can be either a fully-qualified
 path (i.e.
 
\begin_inset Quotes eld
\end_inset

/templates-hidden/default
\begin_inset Quotes erd
\end_inset

), or just the base filename (
\begin_inset Quotes eld
\end_inset

default
\begin_inset Quotes erd
\end_inset

).
 In the latter case, Lift will search all subdirectories of the app root
 for the template.
 By default, Lift will use
\begin_inset Quotes eld
\end_inset

/templates-hidden/default
\begin_inset Quotes erd
\end_inset

 if you don't specify a
\family typewriter
with
\family default
 attribute, so Listings
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Surrounding-your-page"

\end_inset

 and
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Surrounding-with-the-default-template"

\end_inset

 are equivalent.
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "breaklines=true,language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
Surrounding Your Page
\begin_inset CommandInset label
LatexCommand label
name "lst:Surrounding-your-page"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:surround with="default" at="content">
\end_layout

\begin_layout Plain Layout

  <p>Welcome to PocketChange!</p>
\end_layout

\begin_layout Plain Layout

</lift:surround>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
Surrounding with the default template
\begin_inset CommandInset label
LatexCommand label
name "lst:Surrounding-with-the-default-template"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:surround at="content">
\end_layout

\begin_layout Plain Layout

  <p>Welcome to PocketChange!</p>
\end_layout

\begin_layout Plain Layout

</lift:surround>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
Note that you can use multiple surround templates for different functionality,
 and surrounds can be nested.
 For example, you might want to have a separate template for your administrative
 pages that adds a menu to your default template.
 In that case, your
\family typewriter
admin.html
\family default
 could look like Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Adding-an-Admin-menu"

\end_inset

.
 As you can see, we've named our bind point in the admin template
\begin_inset Quotes eld
\end_inset

content
\begin_inset Quotes erd
\end_inset

 so that we keep things consistent for the rest of our templates.
 So if, for example, we were going to nest the template in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Surrounding-your-page"

\end_inset

 above into the
\family typewriter
admin.html
\family default
 template in Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Adding-an-Admin-menu"

\end_inset

, all we'd need to do is change it's
\family typewriter
with
\family default
 attribute from
\begin_inset Quotes eld
\end_inset

default
\begin_inset Quotes erd
\end_inset

 to
\begin_inset Quotes eld
\end_inset

admin.
\begin_inset Quotes erd
\end_inset


\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
Adding an Admin Menu
\begin_inset CommandInset label
LatexCommand label
name "lst:Adding-an-Admin-menu"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:surround with="default" at="content">
\end_layout

\begin_layout Plain Layout

  <lift:Admin.menu />
\end_layout

\begin_layout Plain Layout

  <lift:bind name="content" />
\end_layout

\begin_layout Plain Layout

</lift:surround>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
\align center
\begin_inset Box Shadowbox
position "t"
hor_pos "c"
has_inner_box 1
inner_pos "t"
use_parbox 0
width "75col%"
special "none"
height "1in"
height_special "totalheight"
status open

\begin_layout Plain Layout

\size small
You cannot have a hidden template with the same name as a sub-directory
 of your webapp directory.
 For example, if you had an admin.html template in /templates-hidden, you
 could not also have an admin directory.
 
\end_layout

\end_inset


\end_layout

\begin_layout Subsection
tail
\end_layout

\begin_layout Subsection
TestCond
\end_layout

\begin_layout Subsection
with-param
\end_layout

\begin_layout Subsection
with-resource-id
\end_layout

\begin_layout Subsection
VersionInfo
\end_layout

\begin_layout Subsection
XmlGroup
\end_layout

\begin_layout Section
Head and Tail Merge
\begin_inset CommandInset label
LatexCommand label
name "sec:Head-Tail-Merge"

\end_inset


\end_layout

\begin_layout Standard
Another feature of Lift's template processing is the ability to merge the
 HTML
\family typewriter
head
\family default

\begin_inset Index
status open

\begin_layout Plain Layout
head
\end_layout

\end_inset

 element in a template with the
\family typewriter
head
\family default
 element in the surrounding template.
 In our example, Listing
\begin_inset CommandInset ref
LatexCommand ref
reference "lst:Sample-template"

\end_inset

, notice that we've specified a
\family typewriter
head
\family default
 tag inside the template.
 Without the head merge, this
\family typewriter
head
\family default
 tag would show up in the default template where our template gets bound.
 Lift is smart about this, though, and instead takes the content of the
 
\family typewriter
head
\family default
 element and merges it into the outer template's
\family typewriter
head
\family default
 element.
 This means that you can use a
\family typewriter
surround
\family default
 tag to keep a uniform default template, but still do things such as changing
 the title of the page, adding scripts or special CSS, etc.
 For example, if you have a table in a page that you'd like to style with
 jQuery's TableSorter, you could add a head element to insert the appropriate
 script:
\end_layout

\begin_layout Standard
\begin_inset listings
lstparams "language=XML"
inline false
status open

\begin_layout Plain Layout

\begin_inset Caption

\begin_layout Plain Layout
Using Head Merge
\begin_inset CommandInset label
LatexCommand label
name "lst:Using-Head-Merge"

\end_inset


\end_layout

\end_inset


\end_layout

\begin_layout Plain Layout

<lift:surround with="default" at="foo">
\end_layout

\begin_layout Plain Layout

<head><script src="/scripts/tablesorter.js" type="text/javascript" /><head>
\end_layout

\begin_layout Plain Layout

...
\end_layout

\begin_layout Plain Layout

</lift:surround>
\end_layout

\end_inset


\end_layout

\begin_layout Standard
In this manner, you'll import TableSorter for this template alone.
\end_layout

\begin_layout Section
Binding
\begin_inset CommandInset label
LatexCommand label
name "sec:Binding"

\end_inset


\end_layout

\end_body
\end_document
Something went wrong with that request. Please try again.