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我正在测试Developer site中的Listview示例，这是用Loader和Adapter填充ListView的示例。该应用程序因某些未知错误而失败。我不确定，但怀疑getLoaderManager().initLoader(0, null, this);声明有问题。如何用Loader填充ListView？
模拟器显示“不幸的是，ListViewLoader已停止。” 我也用过，<uses-permission android:name="android.permission.READ_CONTACTS" />之前<application>标签但收到相同的错误。在清单文件中。在logcat中显示以下信息：提前
09-25 22:57:33.853 28524-28618/com.example.listviewloader E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1
Process: com.example.listviewloader, PID: 28524
java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:309)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.SecurityException: Permission Denial: opening provider com.android.providers.contacts.ContactsProvider2 from ProcessRecord{3c98c11 28524:com.example.listviewloader/u0a108} (pid=28524, uid=10108) requires android.permission.READ_CONTACTS or android.permission.WRITE_CONTACTS
at android.os.Parcel.readException(Parcel.java:1599)
at android.os.Parcel.readException(Parcel.java:1552)
at android.app.ActivityManagerProxy.getContentProvider(ActivityManagerNative.java:3550)
at android.app.ActivityThread.acquireProvider(ActivityThread.java:4778)
at android.app.ContextImpl$ApplicationContentResolver.acquireUnstableProvider(ContextImpl.java:2018)
at android.content.ContentResolver.acquireUnstableProvider(ContentResolver.java:1468)
at android.content.ContentResolver.query(ContentResolver.java:475)
at android.content.CursorLoader.loadInBackground(CursorLoader.java:64)
at android.content.CursorLoader.loadInBackground(CursorLoader.java:56)
at android.content.AsyncTaskLoader.onLoadInBackground(AsyncTaskLoader.java:312)
at android.content.AsyncTaskLoader$LoadTask.doInBackground(AsyncTaskLoader.java:69)
at android.content.AsyncTaskLoader$LoadTask.doInBackground(AsyncTaskLoader.java:66)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818) 09-25 22:57:33.859 28524-28621/com.example.listviewloader D/OpenGLRenderer: Use
EGL_SWAP_BEHAVIOR_PRESERVED: true
09-25 22:57:33.863 28524:28524 D/ ]
HostConnection::get() New Host Connection established 0xaa9e84a0, tid 28524
09-25 22:57:34.200 28524-28621/com.example.listviewloader I/OpenGLRenderer: Initialized EGL, version 1.4
09-25 22:57:34.910 28524-28621/com.example.listviewloader E/Surface: getSlotFromBufferLocked: unknown buffer: 0xb40943e0
感谢您对下面的代码中发现任何问题。
import android.app.ListActivity;
import android.content.CursorLoader;
import android.database.Cursor;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.support.v4.widget.DrawerLayout;
import android.util.Log;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.app.LoaderManager;
import android.content.Loader;
import android.widget.SimpleCursorAdapter;
import android.widget.Toast;
public class MainActivity extends ListActivity
implements LoaderManager.LoaderCallbacks<Cursor> {
// This is the Adapter being used to display the list's data
SimpleCursorAdapter mAdapter;
// These are the Contacts rows that we will retrieve
static final String[] PROJECTION = new String[] {ContactsContract.Data._ID,
ContactsContract.Data.DISPLAY_NAME};
// This is the select criteria
static final String SELECTION = "((" +
ContactsContract.Data.DISPLAY_NAME + " NOTNULL) AND (" +
ContactsContract.Data.DISPLAY_NAME + " != ''))";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// For the cursor adapter, specify which columns go into which views
String[] fromColumns = {ContactsContract.Data.DISPLAY_NAME};
int[] toViews = {android.R.id.text1}; // The TextView in simple_list_item_1
// Create an empty adapter we will use to display the loaded data.
// We pass null for the cursor, then update it in onLoadFinished()
mAdapter = new SimpleCursorAdapter(this,
android.R.layout.simple_list_item_1, null,
fromColumns, toViews, 0);
setListAdapter(mAdapter);
// Prepare the loader. Either re-connect with an existing one,
// or start a new one.
getLoaderManager().initLoader(0, null, this); //this seems to be wrong
}
// Called when a new Loader needs to be created
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
// Now create and return a CursorLoader that will take care of
// creating a Cursor for the data being displayed.
return new CursorLoader(this, ContactsContract.Data.CONTENT_URI,
PROJECTION, SELECTION, null, null);
}
// Called when a previously created loader has finished loading
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
// Swap the new cursor in. (The framework will take care of closing the
// old cursor once we return.)
mAdapter.swapCursor(data);
}
// Called when a previously created loader is reset, making the data unavailable
public void onLoaderReset(Loader<Cursor> loader) {
// This is called when the last Cursor provided to onLoadFinished()
// above is about to be closed. We need to make sure we are no
// longer using it.
mAdapter.swapCursor(null);
}
@Override
public void onListItemClick(ListView l, View v, int position, long id) {
// Do something when a list item is clicked
}
w你应该发布错误日志和你班级的导入声明。 – Bob