在我正在开发的应用程序中,我使用带有片段的ViewPager,每个片段独立于ViewPager中的所有其他片段构建自己的菜单。Viewpager初始片段中的操作项不被显示
问题是有时默认情况下由ViewPager初始化(即处于初始状态)的片段没有将其项目填充到操作项目菜单中。更糟糕的是,这个问题只是间歇性地发生。如果我滑过ViewPager足够多,以便片段被迫重新初始化它们,当我向后滑动时,菜单正确填充。
活动码:
package net.solarnz.apps.fragmentsample;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.os.Bundle;
import android.support.v13.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
public class FragmentSampleActivity extends Activity {
private ViewPagerAdapter mViewPagerAdapter;
private ViewPager mViewPager;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
if (mViewPagerAdapter == null) {
mViewPagerAdapter = new ViewPagerAdapter(getFragmentManager());
}
mViewPager = (ViewPager) findViewById(R.id.log_pager);
mViewPager.setAdapter(mViewPagerAdapter);
mViewPager.setCurrentItem(0);
}
private class ViewPagerAdapter extends FragmentStatePagerAdapter {
public ViewPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return 8;
}
@Override
public Fragment getItem(int position) {
Fragment f = Fragment1.newInstance(position);
// f.setRetainInstance(true);
f.setHasOptionsMenu(true);
return f;
}
}
}
片段代码:
package net.solarnz.apps.fragmentsample;
import android.app.Fragment;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
public class Fragment1 extends Fragment {
int mNum;
static Fragment newInstance(int num) {
Fragment1 f = new Fragment1();
// Supply num input as an argument.
Bundle args = new Bundle();
args.putInt("num", num);
f.setArguments(args);
return f;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
mNum = getArguments() != null ? getArguments().getInt("num") : 0;
}
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_list, menu);
}
}
布局:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<android.support.v4.view.ViewPager
android:id="@+id/log_pager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
菜单:
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/menu_refresh"
android:title="Refresh"
android:icon="@android:drawable/ic_delete"
android:showAsAction="ifRoom|withText" />
</menu>
操作菜单被填充:不被填充 http://i.stack.imgur.com/QFMDd.png
操作菜单: http://i.stack.imgur.com/sH5Pp.png
与Solarnz同意似乎没有明显的解决方法。我创建了一个[演示程序](https://github.com/snodnipper/page-flipper-race-condition/),可以让您可靠地重现问题。同样的问题似乎是[在ActionBarSherlock中报告](https://github.com/JakeWharton/ActionBarSherlock/issues/351),我提出了这个问题(http://code.google.com/p/android/issues/detail?id = 29472)在android问题跟踪器中。 – snodnipper 2012-04-25 21:27:46