Android photo gallery

Question

I have created an application with fragments and on gallery fragment whenever I open that fragment it gets closed.

following is the code:

.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_height="match_parent"
    tools:context="junagadh.pkmcollege.com.pkmcollege.bscFragment">

    <Gallery
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/gallery1"
        />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_marginTop="25dp"
        android:layout_height="wrap_content"
        android:id="@+id/imageView1"
        />



</LinearLayout>

and coding:

public class bscFragment extends Fragment {

    int img[] = new int[5];
    public bscFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        for(int i=0;i<img.length;i++) {
            img[i]=getResources().getIdentifier("img"+i,"drawable",getActivity().getPackageName());
        }

        final ImageView iv=(ImageView)getView().findViewById(R.id.imageView1);
        iv.setImageResource(img[0]);

        Gallery gal=(Gallery)getView().findViewById(R.id.gallery1);
        gal.setAdapter(new ImageAdapter(getActivity()));
        gal.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1, int pos, long arg3) {
                iv.setImageResource(img[pos]);
            }
        });

        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_bsc, container, false);
    }

    public class ImageAdapter extends BaseAdapter
    {
        Context c;
        public ImageAdapter(Context c){
            this.c=c;
        }


        @Override
        public int getCount() {
            return img.length;
        }

        @Override
        public Object getItem(int arg0) {
            return arg0;
        }

        @Override
        public long getItemId(int arg0) {
            return arg0;
        }

        @Override
        public View getView(int pos, View arg1, ViewGroup arg2) {
            ImageView iv=new ImageView(c);
            iv.setImageResource(img[pos]);
            iv.setLayoutParams(new Gallery.LayoutParams(120,150));
            iv.setScaleType(ImageView.ScaleType.FIT_XY);
            return iv;
        }
    }

}

Logs:

I/OpenGLRenderer: Initialized EGL, version 1.4
E/EGL_emulation: tid 3280: eglSurfaceAttrib(1165): error 0x3009 (EGL_BAD_MATCH)
W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xa237f040, error=EGL_BAD_MATCH
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
                  Process: junagadh.pkmcollege.com.pkmcollege, PID: 3263
                  java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference
                      at junagadh.pkmcollege.com.pkmcollege.bscFragment.onCreateView(bscFragment.java:34)
                      at android.support.v4.app.Fragment.performCreateView(Fragment.java:2189)
                      at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1299)
                      at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1528)
                      at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1595)
                      at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:757)
                      at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2355)
                      at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2146)
                      at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2098)
                      at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2008)
                      at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:710)
                      at android.os.Handler.handleCallback(Handler.java:739)
                      at android.os.Handler.dispatchMessage(Handler.java:95)
                      at android.os.Looper.loop(Looper.java:148)
                      at android.app.ActivityThread.main(ActivityThread.java:5417)
                      at java.lang.reflect.Method.invoke(Native Method)
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
I/Process: Sending signal. PID: 3263 SIG: 9
Application terminated.

I want to create a photo gallery with one gallery and Imageview. in Gallery it will display all the images from drawable folder with name img0,img1,img2, etc... and the selected image will be display on image view.

Someone help me please solving this problem.

Thanks :)

Answer 1

You can inflate the view first and get the items from inflated view. Then return the view you inflated. Given the null pointer exception on the error log, the following should work.

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_bsc, container, false);
    for(int i=0;i<img.length;i++) {
        img[i]=getResources().getIdentifier("img"+i,"drawable",getActivity().getPackageName());
    }

    final ImageView iv=(ImageView)view.findViewById(R.id.imageView1);
    iv.setImageResource(img[0]);

    Gallery gal=(Gallery)view.findViewById(R.id.gallery1);
    gal.setAdapter(new ImageAdapter(getActivity()));
    gal.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int pos, long arg3) {
            iv.setImageResource(img[pos]);
        }
    });

    return view;
}