Changed JS->Obj-C callback mechanism to use a hidden iframe instead o…

…f "location.replace". [Fixes #6]

Classes/GAScriptBlockObject.m

@@ -65,9 +65,9 @@ - (void)dealloc
 - (NSString *)stringForJavaScript
 {	
     NSAssert(m_block, @"Block for callback cannot be NULL!");
-    GADebugStr(@"ScriptBlockObject: function () { GAJavaScript.invocation('%@', arguments); }", m_blockId);
+    GADebugStr(@"ScriptBlockObject: GAJavaScript.invocation('%@')", m_blockId);
 
-	return [NSString stringWithFormat:@"function () { GAJavaScript.invocation('%@', arguments); }", m_blockId];	
+	return [NSString stringWithFormat:@"GAJavaScript.invocation('%@')", m_blockId];	
 }
 
 @end

Tests/TScriptObject.m

@@ -199,7 +199,13 @@ - (void)testCallFunction
 	GHAssertTrue([retVal isKindOfClass:[NSError class]], nil);
     NSError* myErr = (NSError *)retVal;
     GHAssertEquals([myErr domain], GAJavaScriptErrorDomain, @"Wrong error domain");
-    GHAssertEqualStrings([myErr localizedDescription], @"Result of expression 'func' [undefined] is not an object.", @"Wrong error message");
+
+	// The error message text changed on iOS 5, so we test for it by checking for the new UIWebView method.
+    //
+    if ([_engine.webView respondsToSelector:@selector(mediaPlaybackAllowsAirPlay)])
+        GHAssertEqualStrings([myErr localizedDescription], @"'undefined' is not an object", @"Wrong error message");
+    else
+		GHAssertEqualStrings([myErr localizedDescription], @"Result of expression 'func' [undefined] is not an object.", @"Wrong error message");
 }
 
 - (void)testJavaScriptTrue

ga-js-runtime.js

@@ -26,8 +26,35 @@
  or implied, of Andrew Goodale.
  */ 
 
-GAJavaScript = {
+GAJavaScript = 
+function () {
 
+	/**
+	 * Uses an iframe navigation to cause the UIWebViewDelegate to be called.
+	 * The custom URL scheme identifies this request as the "trigger" to make Obj-C calls.
+	 * Note that call happens asynchronously, so a script can queue several calls that will be invoked in order when the run loop is ready.
+	 */
+	function callScriptEngine () {
+		var iframe = document.getElementById("gajavascript_frame");
+
+		if (iframe === null) {
+			iframe = document.createElement("iframe");
+			iframe.id = "gajavascript_frame";
+			iframe.style = "display: none";
+			iframe.src = "ga-js:makeLotsaCalls";
+
+			document.documentElement.appendChild(iframe);	// will make the callback happen
+		}
+		else {
+			iframe.src = iframe.src;	// a kind of "refresh"
+
+			// Experimental: The two statements below would cause Obj-C to be invoked synchronously.
+//			document.documentElement.removeChild(iframe);
+//			document.documentElement.appendChild(iframe);
+		}
+	}
+
+return {
 	ref: { 
 		index: 0
 	},
@@ -146,22 +173,24 @@ GAJavaScript = {
 	},
 
     performSelector: function (selName) {
-        var newCall = {
+        this.calls.push({
             sel: selName,
             args: Array.prototype.slice.call(arguments)     // Converts it to a true Array
-        };
-        this.calls.push(newCall);
-
-        location.replace("ga-js:makeLotsaCalls");
+        });
+
+        callScriptEngine();
     },
 
-	invocation: function (invocationHash, callArguments) {
-        var newCall = {
-			inv: invocationHash,
-			args: Array.prototype.slice.call(callArguments)     // Converts it to a true Array
-        };
-        this.calls.push(newCall);
+	invocation: function (invocationHash) {
 
-		location.replace("ga-js:makeLotsaCalls");
+		return function () {
+			GAJavaScript.calls.push({
+				inv: invocationHash,
+				args: Array.prototype.slice.call(arguments)     // Converts it to a true Array
+			});
+
+			callScriptEngine();
+		};
 	}
-};
+}
+}();