问题
I'm working on a tabbed application using FragmentTabHost. One of my tabs(Fragments) is a map (extends Fragment), and I can only see the first time I select it, If I select other tab and back to map, app crashes...
The app must be compatible with API8
Main activity
package pack.unimaps2;
import com.google.android.gms.common.GooglePlayServicesUtil;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTabHost;
import android.view.Menu;
public class MainActivity extends FragmentActivity {
private FragmentTabHost mTabHost;
@Override
protected void onCreate(Bundle savedInstanceState) {
GooglePlayServicesUtil.isGooglePlayServicesAvailable(getApplicationContext());
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTabHost = (FragmentTabHost)findViewById(android.R.id.tabhost);
mTabHost.setup(this, getSupportFragmentManager(), R.id.realtabcontent);
mTabHost.addTab(mTabHost.newTabSpec("simple").setIndicator("Ir a..."),
Fragments.RutaHastaTab.class, null);
mTabHost.addTab(mTabHost.newTabSpec("mapa").setIndicator("Mapa"),
Fragments.map.class, null);
mTabHost.addTab(mTabHost.newTabSpec("acercade").setIndicator("Acerca de..."),
Fragments.AcercaDeTab.class, null);
}
}
FragmentsActivity (Omitted first fragment)
package pack.unimaps2;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.google.android.gms.maps.SupportMapFragment;
public class Fragments extends FragmentActivity {
public static class map extends Fragment{
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.map, container, false);
return v;
}
}
public static class AcercaDeTab extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.tab_acercade, container, false);
return v;
}
}
}
And the xml to create the view of map Fragment (map.xml):
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.google.android.gms.maps.SupportMapFragment"/>
Log
03-30 21:07:49.180: E/AndroidRuntime(16464): FATAL EXCEPTION: main
03-30 21:07:49.180: E/AndroidRuntime(16464): android.view.InflateException: Binary XML file line #1: Error inflating class fragment
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.view.LayoutInflater.inflate(LayoutInflater.java:466)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
03-30 21:07:49.180: E/AndroidRuntime(16464): at pack.unimaps2.Fragments$map.onCreateView(Fragments.java:73)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.FragmentManagerImpl.attachFragment(FragmentManager.java:1264)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:672)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:429)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.os.Handler.handleCallback(Handler.java:615)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.os.Handler.dispatchMessage(Handler.java:92)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.os.Looper.loop(Looper.java:137)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.app.ActivityThread.main(ActivityThread.java:4745)
03-30 21:07:49.180: E/AndroidRuntime(16464): at java.lang.reflect.Method.invokeNative(Native Method)
03-30 21:07:49.180: E/AndroidRuntime(16464): at java.lang.reflect.Method.invoke(Method.java:511)
03-30 21:07:49.180: E/AndroidRuntime(16464): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
03-30 21:07:49.180: E/AndroidRuntime(16464): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
03-30 21:07:49.180: E/AndroidRuntime(16464): at dalvik.system.NativeStart.main(Native Method)
03-30 21:07:49.180: E/AndroidRuntime(16464): Caused by: java.lang.IllegalArgumentException: Binary XML file line #1: Duplicate id 0x7f040007, tag null, or parent id 0x0 with another fragment for com.google.android.gms.maps.SupportMapFragment
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:285)
03-30 21:07:49.180: E/AndroidRuntime(16464): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:676)
03-30 21:07:49.180: E/AndroidRuntime(16464): ... 18 more
Don't know what is wrong, thank you for your help...
回答1:
Still looking for an answer?
You can't inflate the layout everytime onCreateView all the time. Use something along the lines of:
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
if (view != null && this.previousContainer == container) {
ViewGroup parent = (ViewGroup) view.getParent();
if (parent != null) {
parent.removeView(view);
}
} else {
try {
view = inflater.inflate(R.layout.map, container, false);
this.previousContainer = container;
} catch (InflateException e) {
Log.w("InflateException happened ou nous", e.getMessage());
}
}
return view;
}
I managed to prevent that and also losing the map when recreating the Fragment (when changing from vertical to landscape for instance)
回答2:
Fragments should have an empty constructor
as follows:
public static class map extends Fragment{
public map(){
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.map, container, false);
// Change the previous line to this:
View v = inflater.inflate(R.layout.map, null);
return v;
}
}
回答3:
the problem is that you are trying to make a new view where there's an old one exist; just simply implement this code.
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (v != null) {
ViewGroup parent = (ViewGroup) v.getParent();
if (parent != null)
parent.removeView(v);
}
try {
v = inflater.inflate(R.layout.map_fragment, container, false);
} catch (InflateException e) {
// map is already there, just return view as it is
}
return v;
}
回答4:
this solution works, but may not be your case. I had the same problem but using a FragmentPagerAdapter inside a ViewPager, not a TabHost.
What I did is to make the ViewPager store all pages all the time:
viewPager.setOffscreenPageLimit(2);
viewPager.setAdapter(adapter);
so my tab with the map fragment (page 0 in my case) will be never deleted and re-created, getting rid of the problem.
value 2 means that it will keep in memory two pages before and two pages after the current one. That will be enough when you have 3 tabs. Feel free to increment it if you have more tabs, but your app's memory consumption will increase too
来源：https://stackoverflow.com/questions/15725581/supportmapfragment-on-a-tab-i-can-only-see-once