我无法在FragmentPagerAdapter中重用片段.使用destroyItem()方法,它正在删除片段,但仍然没有再次调用getItem().只有2-3个图像所以我使用FragmentPagerAdapter而不是FragmentStatePagerAdapter ..
public class ExamplePagerAdapter extends FragmentPagerAdapter {
ArrayList < String > urls;
int size = 0;
public ExamplePagerAdapter(FragmentManager fm, ArrayList < String > res) {
super(fm);
urls = res;
size = urls.size();
}
@Override
public int getCount() {
if (urls == null) {
return 0;
} else {
return size;
}
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
FragmentManager manager = ((Fragment) object).getFragmentManager();
FragmentTransaction trans = manager.beginTransaction();
trans.remove((Fragment) object);
trans.commit();
}
@Override
public Fragment getItem(int …Run Code Online (Sandbox Code Playgroud) 下面是我的ViewpagerAdapter的代码
private class ImagePagerAdapter extends FragmentStatePagerAdapter
{
public ImagePagerAdapter(FragmentManager fm) {
super(fm);
// TODO Auto-generated constructor stub
}
@Override
public Fragment getItem(int arg0) {
// TODO Auto-generated method stub
Fragment fragment = new DemoObjectFragment();
Bundle args = new Bundle();
args.putInt(DemoObjectFragment.ARG_OBJECT, arg0 );
fragment.setArguments(args);
return fragment;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
int returnVal=0;
if (totalPlayer%5==0) {
returnVal= totalPlayer/5;
}
else
{
moduloImage=totalPlayer%5;
returnVal= (totalPlayer/5)+1;
}
return returnVal;
}
@Override
public int getItemPosition(Object object){
return POSITION_NONE; …Run Code Online (Sandbox Code Playgroud) 首先,我使用FragmentStatePagerAdapter为ViewPager提供要显示的片段.
当app处于运行状态(即之后onResume())时,在ViewPager上调用setAdapter将始终工作并使我的ViewPager刷新,getItem(int position)调用适配器中的方法.
但是在方向更改后,如果我在onCreate(Bundle savedInstance)我的activity 的方法中调用setAdapter,getItem(int position)则不会调用该方法,并且会重用旧的片段.
我想也许FragmentManager正在做一些我不明白的事情?片段管理器是在方向更改期间唯一不会被破坏的东西.
谢谢