[英]ListFragment displays empty screen after Transaction when in ViewPager
What I am trying to do 我要做什么
Create a ListFragment (that will be inside a ViewPager) that will replace itself with a new ListFragment containing new data based off of the click position of the previous list. 创建一个ListFragment(将位于ViewPager内),将其替换为一个新的ListFragment,其中包含基于上一个列表的单击位置的新数据的新数据。
The issue I am running into 我遇到的问题
After onListItemClick, the screen does not display anything. 在onListItemClick之后,屏幕不显示任何内容。 I considered just clearing the ListAdapter instead of initializing multiple ListFragments, but I want to retain backStack (I do not know how I would retain backStack without Fragment Transactions) 我考虑过只是清除ListAdapter而不是初始化多个ListFragments,但是我想保留backStack(我不知道如何在没有Fragment Transactions的情况下保留backStack)
MainActivity.java MainActivity.java
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
public class MainActivity extends FragmentActivity {
private ViewPager mPager;
private MainPagerAdapter mPagerAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mPagerAdapter = new MainPagerAdapter(this.getSupportFragmentManager());
mPager = (ViewPager) this.findViewById(R.id.fragment_container);
mPager.setAdapter(mPagerAdapter);
}
private class MainPagerAdapter extends FragmentPagerAdapter {
public MainPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
return new MyListFragment(); //Simplified for the post
}
@Override
public int getCount() {
return 1; //Simplified for the post
}
}
}
MyListFragment.java MyListFragment.java
import java.util.ArrayList;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class MyListFragment extends ListFragment {
private ArrayList<String> titles;
public MyListFragment() {
titles = new ArrayList<String>();
titles.add("one");titles.add("two");titles.add("three");
}
public MyListFragment(ArrayList<String> titles) {
this.titles = titles;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.setListAdapter(new MyListAdapter());
}
@Override
public void onListItemClick (ListView l, View v, int position, long id) {
ArrayList<String> list = new ArrayList<String>();
list.add("1");list.add("2");list.add("3");
getFragmentManager().beginTransaction()
.replace(R.id.fragment_container, new MyListFragment(list))
.addToBackStack(null)
.commit();
}
private class MyListAdapter extends ArrayAdapter<String> {
public MyListAdapter() {
super(getActivity(), android.R.layout.simple_list_item_1, titles);
}
}
}
activity_main.xml activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<android.support.v4.view.ViewPager android:id="@+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
Finally figured it out. 终于想通了。 I created a ListRootFragment that would inflate its layout and add in the ListFragment. 我创建了一个ListRootFragment,它将膨胀其布局并添加到ListFragment中。
ListRootFragment.java ListRootFragment.java
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class ListRootFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment, container, false);
this.getActivity().getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment, new MyListFragment())
.commit();
return view;
}
}
fragment.xml fragment.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="@+id/fragment" >
</LinearLayout>
Updated MainActivity.java 更新了MainActivity.java
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
public class MainActivity extends FragmentActivity {
...
private class MainPagerAdapter extends FragmentStatePagerAdapter {
...
@Override
public Fragment getItem(int position) {
return new ListRootFragment();
}
...
}
}
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.