android-loadermanager

问题 If I have a ViewPager with a certain number of pages, what would be the best way of loading the data for each page using the Loader framework? Each page contains a ListView with its own adapter instance. Use a separate loader for each page; or Use a single loader that checks which pages are not loaded and loads them The thing is, it's possible the user may want to quickly swipe through a bunch of pages and thus it should be easy to "cancel" loading pages that aren't needed for performance

问题 My Custom Adapter that extends SimpleCursorAdapter for my ListFragment does not display the items in my database correctly. it does not display the text in the TextView, what else do I have to do to the cursor for it to show the correct text? I thought I had to override the bindView but that had no effect Setting the adapter: public void populateList(){ String[] fields = new String[] {BowlersDB.NAME}; Cursor c = getActivity().getContentResolver().query(BowlersDB.CONTENT_URI, new String[]

问题 I have a cursor returned on an onLoadFinished callback (from LoaderManager.LoaderCallbacks ), and I want to do some (possibly costly) post-processing on this cursor. So, I'm firing off an AsyncTask that uses this Cursor. However, I'm getting intermittent crashes with this exception: android.database.StaleDataException: Attempted to access a cursor after it has been closed. My suspicion is that this is happening because the cursor (being managed by the Loader in the UI Thread) is being closed

问题 I wish to implement a Loader for in a ListActivity but the activity do not recognize getLoaderManager. @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); dbHelper = new DBHelper(this,DBNAME,FindPackageName(), TABLE_NAME); sql = dbHelper.getReadableDataBase(); //Log.d("Gaurav","Database Open"); String[] from = new String[]{"word","_id","MyList"}; int[] to = new int[]{R.id.listrow }; simpleCursorLoader = new SimpleCursorLoader(this, TABLE_NAME, from,

问题 I would like to follow this nice usability pattern, where app stores data offline for faster response and updates it when it gets new data online. And I use Loaders with LoaderManager . Now, what is the correct approach to implement the aforementioned approach with Loaders ? Currently I use two approaches, which have their downsides and, generally, are not very elegant. Storing the data in the application context instead of SQLite Two separate AsyncTaskLoaders - offlineLoader and onlineLoader

问题 Hi I want to get location from cell tower(Sim card) without internet. I had used below mentioned code it's give me only last location when network available. my requirement is to get location without WiFi or internet. can it's possible? package com.example.gpscelltower; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Timer; import java.util.TimerTask; import android.app.Activity; import android.content.Context; import android

问题 I keep seeing "The application may be doing too much work on its main thread." Is this being caused by swapCursor() in my code below? It appears so: if I remove it, the above warning disappears. I still don't understand why it claims to be the main thread that is causing the problem. I have moved the swapCursor() around into various places such as onLoadFinished() and in loadInBackground() but I get the same result. How can I call swapCursor() so that this warning doesn't appear? The whole

问题 I'm learning about custom providers and loaders. As a simple example I'm trying to implement a GridView that shows the pictures stored in the external SD card. Although I've read a lot (documentation, threads on SO, Google groups, forums...) I'm not able to get my code working. I know that several issues may be present on this example but I want to go step by step. The first error stopping the code is a NullPointerException , so my question is how to fix it. This is a minimal version of my

问题 I have an app with a fairly standard fragment layout. An expandable listview fragment on the left and a panel on the right that is used for different things depending on what the user chooses to do with the list on the left (displaying data, adding new data, etc). I'm using the LoaderManager (first time using loaders) with CommonWare's loaderex library as I have no need or desire to create a Content Provider for my database just so I can use a standard CursorLoader. This setup works great for

问题 I created a loader that descends from AsyncTaskLoader . It works 99% of the time, but there's an edge case where LoaderCallbacks.onLoadFinished() is not called after AsyncTaskLoader.loadInBackground() returns successfully. I don't know what's different in the edge case but I can't think of any reason why the loader would fail between these two calls. Is there anything I could be doing wrong? 回答1: First of all, it is important how you run your Loader: You can run it first time by activity