SupportMapFragment on a tab. I can only see once

Question

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...

Answer 1

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;
}

Answer 2

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

Answer 3

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;
    }

}

Answer 4

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)