I have a fragment that uses multiple CursorLoaders. All works fine. Now I need to add an AsyncTaskLoader as well, to the same fragment.
Question is, how can I use the same LoaderManager.LoaderCallbacks interface to manage both my CursorLoaders and AsyncTaskLoader?
My thought is that since CursorLoader is-a AsyncTaskLoader, then I should be able to adapt the LoaderCallBacks to both, but I may be miss the boat...
这仅在所有加载器返回相同类型时才有效。如果这是真的，那么您只需为您启动的每个加载程序指定唯一的 ID。相同的 ID 被传递到 onCreateLoader() 调用中，因此您只需检查该 ID 以确定要创建的加载程序。
看来我这个问题太晚了，希望它可以帮助一些人。
我刚刚在同一个 Activity 中完成了一个带有多个加载器的项目，一个 CursorLoader 用于数据库，另一个 AsynctaskLoader 用于网络作业。
class YourActivity extends AppCompatActivity implements LoaderManager.LoaderCallbacks {
// you still implements LoaderManager.LoaderCallbacks but without add <returnType>
//and you have to cast the data into your needed data type in onLoadFinished()
Private int loader1 = 1; // eg. CursorLoaderId
private int loader2 =2; //eg. AsynctaskLoaderId
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detail);
// init loader with different Id
getSupportLoaderManager().initLoader(yourLoaderId, null, this);
}
@Override
public Loader onCreateLoader(int id, Bundle args) {
if (id == loader1 ) {
//YourLoaderClass1 is you loaderClass where you implement onStartLoading and loadingInBackground()
return new YourLoaderClass1();
} else if (id == loader2 ) {
return new YourLoaderClass2();
}
return null;
}
@Override
public void onLoadFinished(Loader loader, Object data) {
int id = loader.getId();// find which loader you called
if (id == loader1 ) {
yourMethod1((List< >) data); // eg. cast data to List<String>
} else if (id == loader2 ) {
yourMethod1((String) data); // eg. cast data to String
}
}
@Override
public void onLoaderReset(Loader loader) {
int id = loader.getId();
if (id == loader1 ) {
} else if (id == loader2 ) {
}
}
}