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Null exception in URI file?

My application has a capture button for capturing images using the device’s camera, so I used the captureImage () method in the click event of this button. When I click the button, a null pointer exception is thrown. I may not understand how this happens. Can anyone help? Thanks in advance!

capture button is enabled in the Create () method

photoButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { /* Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); startActivityForResult(cameraIntent, CAMERA_REQUEST);*/ captureImage(); } });

captureImage () method

 private void captureImage() { Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE); fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE); intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // start the image capture Intent startActivityForResult(intent, CAMERA_REQUEST); }

Null pointer exception for this method

  public Uri getOutputMediaFileUri(int type) { return Uri.fromFile(getOutputMediaFile(type)); } /** * returning image / video */ private static File getOutputMediaFile(int type) { // External sdcard location File mediaStorageDir = new File( Environment .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), Config.IMAGE_DIRECTORY_NAME); // Create the storage directory if it does not exist if (!mediaStorageDir.exists()) { if (!mediaStorageDir.mkdirs()) { Log.d(TAG, "Oops! Failed create " + Config.IMAGE_DIRECTORY_NAME + " directory"); return null; } } // Create a media file name String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault()).format(new Date()); File mediaFile; if (type == MEDIA_TYPE_IMAGE) { mediaFile = new File(mediaStorageDir.getPath() + File.separator + "IMG_" + timeStamp + ".jpg"); } else { return null; } return mediaFile; }

Logcat

  java.lang.NullPointerException: file at android.net.Uri.fromFile(Uri.java:447) at com.riafy.user.imagegallerydemo.MainActivity.getOutputMediaFileUri(MainActivity.java:235) at com.riafy.user.imagegallerydemo.MainActivity.captureImage(MainActivity.java:97) at com.riafy.user.imagegallerydemo.MainActivity.access$100(MainActivity.java:29) at com.riafy.user.imagegallerydemo.MainActivity$2.onClick(MainActivity.java:68) at android.view.View.performClick(View.java:4761) at android.view.View$PerformClick.run(View.java:19767) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5312) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:901) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:696)
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4 answers

getOutputMediaFile (type) returns null.

  public Uri getOutputMediaFileUri(int type) { return Uri.fromFile(getOutputMediaFile(type)); }

You come back here:

 // Create the storage directory if it does not exist if (!mediaStorageDir.exists()) { if (!mediaStorageDir.mkdirs()) { Log.d(TAG, "Oops! Failed create " + Config.IMAGE_DIRECTORY_NAME + " directory"); return null; } }

Did you add the following permission

 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

to your manifest?

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My solution was simple.

An error has occurred. Android Manifest set maxSDKVersion to 18 with write permission to the repository. After that, it worked great.

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 File mediaStorageDir = new File( Environment .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), Config.IMAGE_DIRECTORY_NAME);

I directly copied the code to the get started page with Android. My problem was that I ran it on an emulator. Therefore, I think the code above that I used could not evaluate my file system.

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In my case, I recognized the SDK version 23, and it may be necessary to allow runtime permissions to write external storage. So I decided like this:

 public Uri getOutputMediaFileUri(int type) { requestRuntimePermission(); return Uri.fromFile(getOutputMediaFile(type)); } public void requestRuntimePermission() { if (Build.VERSION.SDK_INT >= 23) { if (ContextCompat.checkSelfPermission(context,android.Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { ActivityCompat.requestPermissions(activity, new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1); } } }

Note. Instead of context and activity you can put this higher if applicable

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