fragments in viewpager, no view found error

Question

I have an activity holding a fragment, in this fragment there is a button , when it is clicked, a dialog is popped out.

In this dialog, there is a Viewpager, which holds some fragments to display.

Here are the code and the error, please spare your valuable time to show me where I am wrong. I much appreciate your help.

MainActivity.class

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;

public class MainActivity extends FragmentActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);

    FragmentManager fm = getSupportFragmentManager();
    FragmentTransaction fragmentTransaction = fm.beginTransaction();

    MyFragment fragment = new MyFragment();

    fragmentTransaction.add(R.id.container, fragment);

    fragmentTransaction.commit();

}
}

MyFragment.class

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;

public class MyFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.fragment_sandbox, container, false);
    Button button = (Button) v.findViewById(R.id.button);

    button.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            PagerDialog dialog = new PagerDialog(getActivity(),
                    getChildFragmentManager());
            dialog.show();
        }
    });
    return v;
}
}

PagerDialog.class

import android.app.Dialog;
import android.content.Context;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

public class PagerDialog extends Dialog {

ViewPager mViewPager;
FragmentStatePagerAdapter mAdapter;
FragmentManager mFragmentManager;

public PagerDialog(Context context, FragmentManager fm) {
    super(context);
    mFragmentManager = fm;
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.dialog);
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mAdapter = new MyAdapter(mFragmentManager);
    mViewPager.setAdapter(mAdapter);

}

private class MyAdapter extends FragmentStatePagerAdapter {

    public MyAdapter(FragmentManager fm) {
        super(fm);

    }

    @Override
    public Fragment getItem(int index) {
        return new DummyFragment();
    }

    @Override
    public int getCount() {
        return 2;
    }

}

private class DummyFragment extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater,
            @Nullable ViewGroup container,
            @Nullable Bundle savedInstanceState) {

        View v = inflater.inflate(R.layout.fragment_dummy_layout,
                container, false);
        return v;
    }
}
}

Here is the dialog.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

<android.support.v4.view.ViewPager
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

</LinearLayout>

Here is the error

03-06 19:43:38.487: E/AndroidRuntime(1167): FATAL EXCEPTION: main
03-06 19:43:38.487: E/AndroidRuntime(1167): Process: com.me.sandbox, PID: 1167
03-06 19:43:38.487: E/AndroidRuntime(1167): java.lang.IllegalArgumentException: No view found for id 0x7f05003d (com.mochimira.sandbox:id/pager) for fragment DummyFragment{b2d9f8c8 #0 id=0x7f05003d}
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:939)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1126)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:739)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1489)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:486)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.view.ViewPager.populate(ViewPager.java:1073)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.view.ViewPager.populate(ViewPager.java:919)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1441)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.View.measure(View.java:16497)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.View.measure(View.java:16497)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.View.measure(View.java:16497)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.View.measure(View.java:16497)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.View.measure(View.java:16497)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2291)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.View.measure(View.java:16497)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1916)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1113)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1295)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5670)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.Choreographer.doCallbacks(Choreographer.java:574)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.Choreographer.doFrame(Choreographer.java:544)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.os.Handler.handleCallback(Handler.java:733)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.os.Handler.dispatchMessage(Handler.java:95)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.os.Looper.loop(Looper.java:136)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at android.app.ActivityThread.main(ActivityThread.java:5017)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at java.lang.reflect.Method.invokeNative(Native Method)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at java.lang.reflect.Method.invoke(Method.java:515)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
03-06 19:43:38.487: E/AndroidRuntime(1167): 	at dalvik.system.NativeStart.main(Native Method

Answer 1

I have found a solution to the problem and have modified your classes so that this error no longer occurs.

The only major difference was that you should use a DialogFragment instead of a Dialog, that way you have access to call getChildFragmentManager() and receive the correct FragmentManager from the DialogFragment.

Even though you were using getChildFragmentManager() before, it was coming from MyFragment and the PagerDialog class was not a child fragment in MyFragment.

I have tested the code below, and it should be working fine now.

MyFragment

public class MyFragment extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.fragment_sandbox, container, false);
        Button button = (Button) v.findViewById(R.id.button);

        button.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                DialogFragment newFragment = PagerDialog.newInstance();
                newFragment.show(getChildFragmentManager(), "dialog");
            }

        });

        return v;
    }
}

PagerDialog

public class PagerDialog extends DialogFragment {

    public static PagerDialog newInstance() {
        return new PagerDialog();
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.dialog_fragment, container, false);

        ViewPager mViewPager = (ViewPager) v.findViewById(R.id.view_pager);

        /* Use childFragmentManager here provided from the PagerDialog */
        MyAdapter mAdapter = new MyAdapter(getChildFragmentManager());
        mViewPager.setAdapter(mAdapter);

        return v;
    }

    private class MyAdapter extends FragmentStatePagerAdapter {

        public MyAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int index) {
            return new DummyFragment();
        }

        @Override
        public int getCount() {
            return 2;
        }

    }
}

DummyFragment

public class DummyFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View v = inflater.inflate(R.layout.fragment_dummy_layout, container, false);
        return v;
    }

}

fragment_sandbox.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center">

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Test Fragment Dialog Pager"
        android:textSize="24sp"
        android:padding="20dp" />

</LinearLayout>

dialog_fragment.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="vertical" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Fragment Dialog Title Text "
        android:padding="10dp"
        android:textColor="#333"
        android:textSize="24sp"/>

    <android.support.v4.view.ViewPager
        android:id="@+id/view_pager"
        android:layout_width="match_parent"
        android:layout_height="200dp"/>

</LinearLayout>

fragment_dummy_layout.xml

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Fragment Dummy Text"
        android:textSize="24sp"
        android:textColor="#ff0000"/>

</LinearLayout>

Answer 2

I found in Google a blog post, it says that viewpager doesn't work on Dialog. It also says we should use DialogFragment instead.

Here is the link to that blog: http://www.intellicode.in/viewpager-inside-dialog/