在一些项目中经常会用到把一个列表的数据源按照一定的顺序分组排序例如联系人，日期，地址选择等。 效果如下图所示
Observable.just(dbManager).map(new Function<DBManager, Object>() {
@Override
public Object apply(DBManager dbManager) throws Exception {
sqLiteDatabase = dbManager.initDataBase(getPackageName());
String[] columns = new String[]//列属性
{"cityType", "cityID", "cityName", "parentId"};
String selection = "cityType=?";
String[] selectionArgs = new String[]{"3"};//type为3时查询的是市
List<CityVo> cityVoList = dbManager.query(sqLiteDatabase, columns, selection, selectionArgs);
sqLiteDatabase.close();
return cityVoList;
}
}).compose(RxUtils.schedulersTransformer()).subscribe(new Consumer<List<CityVo>>() {
@Override
public void accept(List<CityVo> cityVoList) throws Exception {
doData(cityVoList);
}
});
Observable.fromIterable(cityVoList).
toSortedList(new Comparator<CityVo>() {
@Override
public int compare(CityVo o1, CityVo o2) {
//a-z排序
String a = o1.getPinYin();
String b = o2.getPinYin();
return a.compareTo(b);
}
}).subscribe(new Consumer<List<CityVo>>() {
@Override
public void accept(List<CityVo> cityVoList) throws Exception {
pickCityAdapter.addHeaderView(headerView);
pickCityAdapter.setNewData(cityVoList);
//添加了头部,所以keys要从1开始
keys.put(1, "A");
letterIndexes.put("#", 0);
letterIndexes.put("A", 1);
for (int i = 0; i < cityVoList.size(); i++) {
if (i < cityVoList.size() - 1) {
//首字母不同,设为ky
String pre = cityVoList.get(i).getPinYin().substring(0, 1).toUpperCase();
String next = cityVoList.get(i + 1).getPinYin().substring(0, 1).toUpperCase();
if (!pre.equals(next)) {
keys.put(i + 2, next);
letterIndexes.put(next, i + 2);
}
}
}
floatingItemDecoration.setKeys(keys);
}
});
