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我被困在以下情况。onLoadFinished后列表项不显示
我和活动实现了2个选项卡和一个pageradapter，其上有2个片段，我使用ActionBarSherlock出于兼容目的。
有问题的片段从SherlockListFragment扩展并实现LoaderManager.LoaderCallbacks。
我创建了一个自定义ArrayListAdapter和一个自定义的Loader扩展AsyncLoader。
问题是，当加载器完成加载任务时，listview不刷新，它只有显示空白页。
我跟着这个solution但它不能解决我的问题。
这是我的片段布局xml文件。
<LinearLayout android:id="@+id/progressContainer"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone"
android:gravity="center">
<ProgressBar style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:paddingTop="4dip"
android:singleLine="true" />
</LinearLayout>
<FrameLayout android:id="@+id/listContainer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin" >
<ListView
android:id="@id/android:list"
android:layout_width="match_parent"
android:layout_height="0dp"
android:background="@color/abs__background_holo_light"
android:divider="@android:color/transparent"
android:dividerHeight="@dimen/activity_horizontal_margin"
android:drawSelectorOnTop="false"
android:headerDividersEnabled="true"
android:smoothScrollbar="true"
/>
<TextView
android:id="@android:id/empty"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FFFFFF"
android:gravity="center"
android:text="no hay rumores"
/>
这是自定义加载程序代码
package *.android.core;
import android.content.Context;
import android.support.v4.content.AsyncTaskLoader;
import *.Rumor;
import *.DownloadHelper;
import java.util.List;
public class RumorListLoader extends AsyncTaskLoader<List<Rumor>> {
List<Rumor> mRumors;
Context mContext;
/**
* Constructor.
*
* @param context
*/
public RumorListLoader(final Context context) {
super(context);
this.mContext = context;
}
/*
* (non-Javadoc)
* @see android.support.v4.content.Loader#deliverResult(java.lang.Object)
*/
@Override
public void deliverResult(final List<Rumor> data) {
if (isReset()) {
if (data != null) {
onReleaseResources(data);
}
}
final List<Rumor> oldList = data;
this.mRumors = data;
if (isStarted()) {
super.deliverResult(data);
}
if (oldList != null) {
onReleaseResources(oldList);
}
}
/*
* (non-Javadoc)
* @see android.support.v4.content.Loader#isReset()
*/
@Override
public boolean isReset() {
// TODO Auto-generated method stub
return super.isReset();
}
@Override
public List<Rumor> loadInBackground() {
final List<Rumor> rumores = DownloadHelper.downloadPreviousRumors(this.mContext);
return rumores;
}
/*
* (non-Javadoc)
* @see
* android.support.v4.content.AsyncTaskLoader#onCanceled(java.lang.Object)
*/
@Override
public void onCanceled(final List<Rumor> data) {
// TODO Auto-generated method stub
super.onCanceled(data);
onReleaseResources(data);
}
/**
* Helper function that takes care of releasing resources.
*
* @param apps
*/
protected void onReleaseResources(final List<Rumor> apps) {
}
/*
* (non-Javadoc)
* @see android.support.v4.content.Loader#onReset()
*/
@Override
protected void onReset() {
// TODO Auto-generated method stub
super.onReset();
onStopLoading();
if (this.mRumors != null) {
onReleaseResources(this.mRumors);
this.mRumors = null;
}
}
/*
* (non-Javadoc)
* @see android.support.v4.content.Loader#onStartLoading()
*/
@Override
protected void onStartLoading() {
if (this.mRumors != null) {
deliverResult(this.mRumors);
}
if (takeContentChanged() || this.mRumors == null) {
forceLoad();
}
}
/*
* (non-Javadoc)
* @see android.support.v4.content.Loader#onStopLoading()
*/
@Override
protected void onStopLoading() {
// TODO Auto-generated method stub
super.onStopLoading();
cancelLoad();
}
}
最后是这样的片段类
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.Loader;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.AnimationUtils;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
import com.actionbarsherlock.app.SherlockListFragment;
import com.actionbarsherlock.view.Menu;
import com.actionbarsherlock.view.MenuInflater;
import com.actionbarsherlock.view.MenuItem;
import java.util.ArrayList;
import java.util.List;
public class RumorsFragment extends SherlockListFragment implements
LoaderManager.LoaderCallbacks<List<Rumor>> {
protected Context mContext;
public static final String ARG_SECTION_NUMBER = "section_number";
protected final static int RUMOR_LOADER_CODE = 100;
private final static String TAG = "ru_rufragment";
protected RumorAdapter mAdapter;
protected View mProgressContainer;
protected View mListContainer;
boolean mListShown;
public ListView mList;
View mEmptyView;
TextView mStandardEmptyView;
CharSequence mEmptyText;
private LoaderManager.LoaderCallbacks<List<Rumor>> mCallbacks;
final private Handler mHandler = new Handler();
final private Runnable mRequestFocus = new Runnable() {
public void run() {
mList.focusableViewAvailable(mList);
}
};
/**
* Constructor.
*/
public RumorsFragment() {
}
/**
* Setup the list data.
*/
protected void init() {
}
@Override
public void onActivityCreated(final Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
// Initially there is no data
this.mContext = getSherlockActivity();
// Create an empty adapter to display the data.
this.mAdapter = new RumorAdapter(this.mContext, R.layout.rumor_item);
setListAdapter(this.mAdapter);
setEmptyText("Sin datos");
setListShown(false);
mCallbacks = this;
getLoaderManager().initLoader(RUMOR_LOADER_CODE, null, mCallbacks);
}
@Override
public void onAttach(final Activity activity) {
super.onAttach(activity);
this.mContext = getSherlockActivity();
}
@Override
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// This fragment adds elements to the action bar
setHasOptionsMenu(true);
}
@Override
public Loader<List<Rumor>> onCreateLoader(final int arg0, final Bundle data) {
return new RumorListLoader(this.mContext);
}
@Override
public void onCreateOptionsMenu(final Menu menu, final MenuInflater inflater) {
// TODO Auto-generated method stub
super.onCreateOptionsMenu(menu, inflater);
}
@Override
public View onCreateView(final LayoutInflater inflater, final ViewGroup container,
final Bundle savedInstanceState) {
final View fragmentView = inflater.inflate(R.layout.fragment_rumors, container, false);
setRetainInstance(true);
return fragmentView;
}
@Override
public void onDetach() {
// TODO Auto-generated method stub
super.onDetach();
}
@Override
public void onLoaderReset(final Loader<List<Rumor>> arg0) {
this.mAdapter.clear();
}
@Override
public void onLoadFinished(final Loader<List<Rumor>> loader, final List<Rumor> data) {
Log.i(TAG, "Gets to onLoadFinished");
switch (loader.getId()) {
case RUMOR_LOADER_CODE:
mAdapter.setData(data);
// The list should now be shown;
if (isResumed()) {
setListShown(true);
} else {
setListShownNoAnimation(true);
}
}
}
@Override
public boolean onOptionsItemSelected(final MenuItem item) {
// TODO Auto-generated method stub
return super.onOptionsItemSelected(item);
}
@Override
public void onPrepareOptionsMenu(final Menu menu) {
// TODO Auto-generated method stub
super.onPrepareOptionsMenu(menu);
}
public void setListShown(Boolean shown, boolean animate) {
ensureList();
if (mListShown == shown) {
return;
}
mListShown = shown;
if (shown) {
if (animate) {
mProgressContainer.startAnimation(AnimationUtils.loadAnimation(getSherlockActivity(), android.R.anim.fade_out));
mListContainer.startAnimation(AnimationUtils.loadAnimation(getSherlockActivity(), android.R.anim.fade_in));
} else {
mProgressContainer.clearAnimation();
mListContainer.clearAnimation();
}
mProgressContainer.setVisibility(View.GONE);
mListContainer.setVisibility(View.VISIBLE);
} else {
if (animate) {
mProgressContainer.startAnimation(AnimationUtils.loadAnimation(getSherlockActivity(), android.R.anim.fade_in));
mListContainer.startAnimation(AnimationUtils.loadAnimation(getSherlockActivity(), android.R.anim.fade_out));
} else {
mProgressContainer.clearAnimation();
mListContainer.clearAnimation();
}
mProgressContainer.setVisibility(View.VISIBLE);
mListContainer.setVisibility(View.GONE);
}
}
public void setListShown(boolean shown) {
setListShown(shown, true);
}
public void setListShownNoAnimation(boolean shown) {
setListShown(shown, false);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
ensureList();
}
@Override
public void onDestroyView() {
mHandler.removeCallbacks(mRequestFocus);
mList = null;
mListShown = false;
mEmptyView = mProgressContainer = mListContainer = null;
mStandardEmptyView = null;
super.onDestroyView();
}
public ListView getListView() {
ensureList();
return mList;
}
public void setEmptyText(CharSequence text) {
ensureList();
if(mStandardEmptyView == null) {
throw new IllegalStateException("Cant be used");
}
mStandardEmptyView.setText(text);
if(mEmptyText == null) {
mList.setEmptyView(mStandardEmptyView);
}
mEmptyText = text;
}
private void ensureList() {
if (mList != null) {
return;
}
View root = getView();
if (root == null) {
throw new IllegalStateException("View not created");
}
if(root instanceof ListView) {
mList = (ListView) root;
} else {
mStandardEmptyView = (TextView) root.findViewById(android.R.id.empty);
if (mStandardEmptyView == null) {
mEmptyView = root.findViewById(android.R.id.empty);
} else {
mStandardEmptyView.setVisibility(View.GONE);
}
mProgressContainer = root.findViewById(R.id.progressContainer);
mListContainer = root.findViewById(R.id.listContainer);
View rawListView = root.findViewById(android.R.id.list);
if(!(rawListView instanceof ListView)) {
if (rawListView == null) {
throw new RuntimeException("Listview argument android.R.id.list");
}
throw new RuntimeException("Content has view with id attribute 'android.R.id.list' "
+ "that is not a ListView class");
}
mList = (ListView) rawListView;
if (mEmptyView != null) {
mList.setEmptyView(mEmptyView);
} else if (mEmptyText != null) {
mStandardEmptyView.setText(mEmptyText);
mList.setEmptyView(mStandardEmptyView);
}
}
mListShown = true;
//mList.setOnClickListener(mOn)
if (mAdapter != null) {
ListAdapter adapter = mAdapter;
mAdapter = null;
setListAdapter(adapter);
} else {
if (mProgressContainer != null) {
setListShown(false, false);
}
}
mHandler.post(mRequestFocus);
}
}