我使用CursorLoader查询结果,这不是我想要在ListFramgenet中显示的顺序.怎么排序呢？
我用它来设置适配器：
mAdapter = new SimpleCursorAdapter(getActivity(),android.R.layout.simple_list_item_2,null,new String[] { "name","distance"},new int[] { android.R.id.text1,android.R.id.text2 },0);
setListAdapter(mAdapter);
// Start out with a progress indicator.
setListShown(false);
// Prepare the loader. Either re-connect with an existing one,// or start a new one.
getLoaderManager().initLoader(0,this);
创建加载器：
public Loader<Cursor> onCreateLoader(int id,Bundle args) {
return new CursorLoader(getActivity(),Uri.withAppendedPath(TraceTable.CONTENT_URI,"latest"),MEMBERS_PROJECTION,null);
}
public void onLoadFinished(Loader<Cursor> loader,Cursor data) {
mAdapter.changeCursor(data);
// The list should now be shown.
if (isResumed()) {
setListShown(true);
} else {
setListShownNoAnimation(true);
}
}
嗯,查询结果有纬度和经度.我想计算我的位置和这些结果之间的距离.并按距离asc排序.
怎么排序呢？任何答案都会被批评
解决方法
这实际上非常简单：
由此：
new CursorLoader(getActivity(),null);
对此：
// You could have them calculated in the projection like this:
String[] projection = { COLUMN1 + " * " + COLUMN2 + " as data",// Whatever your calculations are
COLUMN1,COLUMN2,COLUMN3,etc.. };
new CursorLoader(getActivity(),projection,"data ASC");
请记住,如果您的提供商中有一些方法可以检查投射并引发异常,您必须在进行测试时将其注释掉,或者将新列(您计算的那个)添加到官方投影数组中.
