Android: NPE happens when getting picture from camera
I have a problem on my Android app. I'm using MediaStore.ACTION_IMAGE_CAPTURE intent to take picture from camera. It worked all most of devices but I got the following crash errors on DroidX device from android market.
I think imageCaptureUri can not be null in this case. So it is not the cause.
Do you have any ideas? Is it a firmware error?
java.lang.NullPointerException at android.content.ContentResolver.openInputStream(ContentResolver.java:286) at com.eb.android.activity.AddActivity.getBase64Receipt(AddActivity.java:193) at com.eb.android.activity.AddActivity.publishReceipt(AddActivity.java:204) at com.eb.android.activity.AddActivity.access$0(AddActivity.java:203) at com.eb.android.activity.AddActivity$1.run(AddActivity.java:50) at java.lang.Thread.run(Thread.java:1102)
java.lang.NullPointerException at android.content.ContentResolver.openInputStream(ContentResolver.java:288) at com.eb.android.activity.AddActivity.getBase64Receipt(AddActivity.java:193) at com.eb.android.activity.AddActivity.publishReceipt(AddActivity.java:204) at com.eb.android.activity.AddActivity.access$0(AddActivity.java:203) at com.eb.android.activity.AddActivity$1.run(AddActivity.java:50) at java.lang.Thread.run(Thread.java:1096)
This is my implementation:
public class AddActivity extends Activity {
public static final int TAKE_RECEIPT = 2;
private Uri imageCaptureUri;
private Runnable submitReceiptRunnable = new Runnable() {
public void run() {
publishReceipt();
}
};
private ProgressDialog progressDialog;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add);
registerListeners();
}
public void onActivityResult(int reqCode, int resultCode, Intent data) {
super.onActivityResult(reqCode, resultCode, data);
switch (reqCode) {
case (TAKE_RECEIPT):
takeReceiptCallback(resultCode, data);
break;
}
}
private void registerListeners() {
ImageView addReceiptButton = (ImageView) findViewById(R.id.AddReceiptButton);
addReceiptButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
takePictureFromCamera();
}
});
}
private void takePictureFromCamera() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
imageCaptureUri = Uri.fromFile(new File(Environment.getExternalStorageDirectory(), "tmp_receipt_"
+ String.valueOf(System.currentTimeMillis()) + ".jpg"));
intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, imageCaptureUri);
intent.putExtra("return-data", true);
startActivityForResult(intent, TAKE_RECEIPT);
}
private void takeReceiptCallback(int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK) {
submitReceipt();
}
}
private void submitReceipt() {
Thread thread = new Thread(null, submitReceiptRunnable);
thread.start();
progressDialog = ProgressDialog.show(this, "Please wait...", "Publishing receipt ...", true);
}
private String getBase64Receipt() {
try {
InputStream inputStream = getContentResolver().openInputStream(imageCaptureUri);
byte[] bytes = CommonUtil.getBytesFromInputStream(inputStream);
return Base64.encodeBytes(bytes);
} catch (IOException e) {
Log.e(TAG, e.getMessage(), e);
}
return null;
}
private void publishReceipt() {
String receipt = getBase64Receipt();
...
}
}
Are you sure that image crop mode forcing
intent.putExtra("return-data", true);
works correctly for the device you use. Correct me if I am wrong, but it is not safe and not well documented approach. Here you can find example of working code without cropping.
UPDATE: Issue you are facing with has long history, also at SO:
https://stackoverflow.com/questions/3904685/unable-to-find-com-android-camera-cropimage-activity-in-android
Issue I experienced was using crop immediatelly after image was taken by the camera. Also, it is not compatible through different Android versions, so if you get it working for 1.5 maybe it will not work for 2.3. Definitely something is wrong, as may be concluded from the Android Developer Group posts:
http://groups.google.com/group/android-developers/browse_thread/thread/2dd647523926192c/569f36b5b28f2661?lnk=gst&q=Crop+image+intent#569f36b5b28f2661
http://groups.google.com/group/android-developers/browse_thread/thread/2dd647523926192c/dcbe5aef29eddad6?lnk=gst&q=Crop+image+intent#dcbe5aef29eddad6
http://groups.google.com/group/android-developers/browse_thread/thread/d7b6a133c164aa17/184bf3b85da2ce58?lnk=gst&q=Crop+image+intent#184bf3b85da2ce58
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