List all the images on android device

2018-07-04 18:34:59

I was trying to list all the images in android device with their paths since 14 hours straight but I wasn't able to .. It keeps giving me "java.lang.RuntimeException: Unable to start activity ComponentInfo" error.

I don't understand why..

Any help??

package com.example.allpicsexample;

import android.app.Activity; 
import android.content.Context; 
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle; 
import android.provider.MediaStore;
import android.view.Menu; 
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView; 
import android.widget.AdapterView.OnItemClickListener;

/** * Displays images from an SD card. */ public class MainActivity extends Activity {

/**
 * Cursor used to access the results from querying for images on the SD card.
 */
private Cursor cursor;
/*
 * Column index for the Thumbnails Image IDs.
 */
private int columnIndex;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    String filePath = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DATA));
    System.out.println("the path is : "+filePath);

}
}

and here is the LogCat info:

11-14 08:29:01.739: D/AndroidRuntime(16788): Shutting down VM 11-14 08:29:01.739: W/dalvikvm(16788): threadid=1: thread exiting with uncaught exception (group=0x40018578) 11-14 08:29:01.749: E/AndroidRuntime(16788): FATAL EXCEPTION: main 11-14 08:29:01.749: E/AndroidRuntime(16788): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.allpicsexample/com.example.allpicsexample.MainActivity}: java.lang.NullPointerException 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.ActivityThread.access$1500(ActivityThread.java:117) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.os.Handler.dispatchMe ssage(Handler.java:99) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.os.Looper.loop(Looper.java:130) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.ActivityThread.main(ActivityThread.java:3687) 11-14 08:29:01.749: E/AndroidRuntime(16788): at java.lang.reflect.Method.invokeNative(Native Method) 11-14 08:29:01.749: E/AndroidRuntime(16788): at java.lang.reflect.Method.invoke(Method.java:507) 11-14 08:29:01.749: E/AndroidRuntime(16788): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867) 11-14 08:29:01.749: E/AndroidRuntime(16788): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625) 11-14 08:29:01.749: E/AndroidRuntime(16788): at dalvik.system.NativeStart.main(Native Method) 11-14 08:29:01.749: E/AndroidRuntime(16788): Caused by: java.lang.NullPointerException 11-14 08:29:01.749: E/AndroidRuntime(16788): at com.example.allpicsexample.MainActivity.onCreate(MainActivity.java:37) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 11-14 08:29:01.749: E/AndroidRuntime(16788): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615) 11-14 08:29:01.749: E/AndroidRuntime(16788): ... 11 more

Here is the 2nd crash log after implementing Abhishek's code

11-14 10:00:20.159: D/AndroidRuntime(19266): Shutting down VM 11-14 10:00:20.159: W/dalvikvm(19266): threadid=1: thread exiting with uncaught exception (group=0x40018578) 11-14 10:00:20.189: E/AndroidRuntime(19266): FATAL EXCEPTION: main 11-14 10:00:20.189: E/AndroidRuntime(19266): android.app.SuperNotCalledException: Activity {com.example.allpicsexample/com.example.allpicsexample.MainActivity} did not call through to super.onCreate() 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1617) 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667) 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.app.ActivityThread.access$1500(ActivityThread.java:117) 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935) 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.os.Handler.dispatchMessage(Handl er.java:99) 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.os.Looper.loop(Looper.java:130) 11-14 10:00:20.189: E/AndroidRuntime(19266): at android.app.ActivityThread.main(ActivityThread.java:3687) 11-14 10:00:20.189: E/AndroidRuntime(19266): at java.lang.reflect.Method.invokeNative(Native Method) 11-14 10:00:20.189: E/AndroidRuntime(19266): at java.lang.reflect.Method.invoke(Method.java:507) 11-14 10:00:20.189: E/AndroidRuntime(19266): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867) 11-14 10:00:20.189: E/AndroidRuntime(19266): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625) 11-14 10:00:20.189: E/AndroidRuntime(19266): at dalvik.system.NativeStart.main(Native Method)

You are getting the exception because you have not initialized cursor object. You can use the below code to get path of all the images.

final String[] columns = { MediaStore.Images.Media.DATA, MediaStore.Images.Media._ID };
        final String orderBy = MediaStore.Images.Media._ID;
        //Stores all the images from the gallery in Cursor
        Cursor cursor = getContentResolver().query(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI, columns, null,
                null, orderBy);
        //Total number of images
        int count = cursor.getCount();

        //Create an array to store path to all the images
        String[] arrPath = new String[count];

        for (int i = 0; i < count; i++) {
            cursor.moveToPosition(i);
            int dataColumnIndex = cursor.getColumnIndex(MediaStore.Images.Media.DATA);
            //Store the path of the image
            arrPath[i]= cursor.getString(dataColumnIndex);
            Log.i("PATH", arrPath[i]);
        }

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