我正在使用此库https://github.com/chrisbanes/Android-PullToRefresh来实现可刷新的网格视图，但出现此错误：
android.view.InflateException: Binary XML file line #8: Error inflating class com.handmark.pulltorefresh.library.PullToRefreshGridView
at android.view.LayoutInflater.createView(LayoutInflater.java:518)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:570)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:623)
at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
at com.example.retrievetweets.FragmentPhotos.onCreateView(FragmentPhotos.java:55)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461)
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1011)
at android.support.v4.view.ViewPager.populate(ViewPager.java:880)
at android.support.v4.view.ViewPager$3.run(ViewPager.java:238)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3687)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.constructNative(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:415)
at android.view.LayoutInflater.createView(LayoutInflater.java:505)
... 24 more
Caused by: java.lang.NullPointerException
at com.handmark.pulltorefresh.library.internal.IndicatorLayout.<init>(IndicatorLayout.java:66)
at com.handmark.pulltorefresh.library.PullToRefreshAdapterViewBase.addIndicatorViews(PullToRefreshAdapterViewBase.java:355)
at com.handmark.pulltorefresh.library.PullToRefreshAdapterViewBase.updateUIForMode(PullToRefreshAdapterViewBase.java:328)
at com.handmark.pulltorefresh.library.PullToRefreshBase.init(PullToRefreshBase.java:1142)
at com.handmark.pulltorefresh.library.PullToRefreshBase.<init>(PullToRefreshBase.java:113)
at com.handmark.pulltorefresh.library.PullToRefreshAdapterViewBase.<init>(PullToRefreshAdapterViewBase.java:74)
at com.handmark.pulltorefresh.library.PullToRefreshGridView.<init>(PullToRefreshGridView.java:35)
... 27 more
这是xml：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<!-- The PullToRefreshGridView replaces a standard GridView widget. -->
<com.handmark.pulltorefresh.library.PullToRefreshGridView
xmlns:ptr="http://schemas.android.com/apk/res-auto"
android:id="@+id/pull_refresh_grid"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:numColumns="auto_fit"
android:verticalSpacing="0dp"
android:horizontalSpacing="1dp"
android:columnWidth="80dp"
android:stretchMode="columnWidth"
android:gravity="fill"
ptr:ptrMode="both"
ptr:ptrDrawable="@drawable/default_ptr_rotate"
/>
<ProgressBar
android:id="@+id/progressBar"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:indeterminateOnly="true"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
</RelativeLayout>
这是FragmentPhotos中onCreateView方法的java代码（第55行是这个“ll =（RelativeLayout）inflater.inflate（R.layout.activity_grid_view”）：
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
ref = "";
fa = getActivity();
ll = (RelativeLayout) inflater.inflate(R.layout.activity_grid_view,
container, false);
bar = (ProgressBar) ll.findViewById(R.id.progressBar);
mPullRefreshGridView = (PullToRefreshGridView) ll
.findViewById(R.id.pull_refresh_grid);
mGridView = mPullRefreshGridView.getRefreshableView();
// Set a listener to be invoked when the list should be refreshed.
mPullRefreshGridView
.setOnRefreshListener(new OnRefreshListener<GridView>() {
@Override
public void onRefresh(
PullToRefreshBase<GridView> refreshView) {
// TODO Auto-generated method stub
if (NetworkReceiver.mobileConnected) {
new GetDataTaskWhitoutLoading().execute();
} else {
Toast.makeText(
getActivity(),
"Ahora mismo no se pueden cargar nuevos datos."
+ " Comprueba la conexi—n a Internet.",
Toast.LENGTH_LONG).show();
mPullRefreshGridView.onRefreshComplete();
}
}
});
mGridView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView parent, View v, int position,
long id) {
// Do something in response to the click
Intent intent = new Intent(fa, ImageSelected.class);
intent.putExtra("URL_image", mListItems.get(position)
.subSequence(0, mListItems.get(position).length() - 6));
startActivity(intent);
}
});
mListItems = new ArrayList<String>();
mAdapter = new FotosItemAdapter(fa, R.layout.image_group, mListItems);
mGridView.setAdapter(mAdapter);
if (NetworkReceiver.mobileConnected) {
GetDataTask.newInstance(bar).execute();
}
return ll;
}
谢谢！！