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Android, Glide Image Loading Library: NullPointerException, ProviderInfo

Just getting into the Glide image loading library for Android. Currently working with some code from here:
https://github.com/bumptech/glide/issues/459
My full project is here is you want to look at it:
https://github.com/mhurwicz/glide02
I'm getting the following exception when I run the app in the emulator in Android Studio:
java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.XmlResourceParser android.content.pm.ProviderInfo.loadXmlMetaData(android.content.pm.PackageManager, java.lang.String)' on a null object reference
This is the key statement in MainActivity:
new ShareTask(this).execute("http://thelink");
(thelink is actually goo.gl/gEgYUd -- couldn't leave that in above because stackoverflow doesn't allow URL shorteners. )
Here is my code for the ShareTask class
class ShareTask extends AsyncTask<String, Void, File> {
private final Context context;
public ShareTask(Context context) {
this.context = context;
}
#Override protected File doInBackground(String... params) {
String url = params[0]; // should be easy to extend to share multiple images at once
try {
return Glide
.with(context)
.load(url)
.downloadOnly(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL)
.get() // needs to be called on background thread
;
} catch (Exception ex) {
Log.w("SHARE", "Sharing " + url + " failed", ex);
return null;
}
}
#Override protected void onPostExecute(File result) {
if (result == null) { return; }
Uri uri = FileProvider.getUriForFile(context, context.getPackageName(), result);
share(uri); // startActivity probably needs UI thread
}
private void share(Uri result) {
Intent intent = new Intent(Intent.ACTION_SEND);
intent.setType("image/jpeg");
intent.putExtra(Intent.EXTRA_SUBJECT, "Shared image");
intent.putExtra(Intent.EXTRA_TEXT, "Look what I found!");
intent.putExtra(Intent.EXTRA_STREAM, result);
context.startActivity(Intent.createChooser(intent, "Share image"));
}
}
Using debug, it seems I may be running into trouble at the get() statement. For one thing, the width and the height are very large negative numbers. (See the code highlighted in green below.) Then the get() statement returns null. (See the code highlighted in red below.)
Thanks in advance for any help you can provide!

The NPE is coming from FileProvider.getUriForFile because you're passing in the wrong authority. You declared android:authorities="com.example.fileprovider" in the manifest, but you're using the package name at the call. This fails to resolve the info in FileProvider.parsePathStrategy. Match those two strings up and you'll be good to go.
The easiest fix is to use android:authorities="${applicationId}", this leads to 0 hardcoded strings, so you can keep using context.getPackageName().
Regarding your concerns during debug:
Target.SIZE_ORIGINAL is declared to be MIN_VALUE, hence the large number
it's not returning null, IDEA is just confused about where it is in the method, that return null; shouldn't be executed if it fails in the FileProvider code.
doGet(null): null is the timeout here, it's guarded properly in code
I've run the app and weirdly I got a log line saying
W/SHARE: Sharing http://... failed
but not a stack trace, which is weird, because ex cannot be null in a catch!

CN1 CodeScanner not working

I am having issues with the CodeScanner not returning values in my application.
This project I have had unchanged for a year and it was working, but there were some new changes that had to be done and when I was making them I noticed I was using a now deprecated scanner and I was to use the new library. I implemented it into the application and it loads correctly, but after I scan the QR code it never goes into the Completed method.
import com.codename1.ext.codescan.CodeScanner;
import com.codename1.ext.codescan.ScanResult;
...
if (CodeScanner.isSupported()) {
CodeScanner.getInstance().scanQRCode(new ScanResult() {
public void scanCompleted(String contents, String formatName, byte[] rawBytes) {
Dialog.show("Scanning Completed", "Scanning Completed", "OK", null);
}
public void scanCanceled() {
Dialog.show("Scanning Cancelled", "Scanning was cancelled", "OK", null);
}
public void scanError(int errorCode, String message) {
NoScanner(2);
}
});
} else {
NoScanner(2);
}
I am hoping I can get some help as to why it suddenly doesn't want to return the scanned value or even enter the various methods.
This was tested on Android, there is also an iOS build but I don't have a device handy for testing

There was a regression in intent handling that we fixed over the weekend. Please try this again and see if the issue resolved itself.

Changing Flash setting of Android Camera 2 at runtime

Basically, what I am trying to do is change the CONTROL_AE_MODE by button click in the app. The user can use AUTO flash(ON_AUTO_FLASH), turn if ON(ON_ALWAYS_FLASH), or OFF(CONTROL_AE_MODE_OFF).
In this example: https://github.com/googlesamples/android-Camera2Basic/blob/master/Application/src/main/java/com/example/android/camera2basic/Camera2BasicFragment.java
Line 818, they set the flash once:
// Use the same AE and AF modes as the preview.
captureBuilder.set(CaptureRequest.CONTROL_AF_MODE,
CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
setAutoFlash(captureBuilder);
// Orientation
int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, ORIENTATIONS.get(rotation));
CameraCaptureSession.CaptureCallback CaptureCallback
= new CameraCaptureSession.CaptureCallback() {
#Override
public void onCaptureCompleted(#NonNull CameraCaptureSession session,
#NonNull CaptureRequest request,
#NonNull TotalCaptureResult result) {
showToast("Saved: " + mFile);
Log.d(TAG, mFile.toString());
unlockFocus();
}
};
mCaptureSession.stopRepeating();
mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null);
And then builds the CaptureSession at line 840.
Is there a way to change the CONTROL_AE_MODE after the preview is made?
I have tried remaking the session, which kinda worked:
if(flashMode == CameraView.CAMERA_FLASH_ON){
Log.e("CAMERA 2", "FLASH ON");
mPreviewCaptureRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_ALWAYS_FLASH);
}else if(flashMode == CameraView.CAMERA_FLASH_OFF){
Log.e("CAMERA 2", "FLASH OFF");
mPreviewCaptureRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_OFF);
}else if(flashMode == CameraView.CAMERA_FLASH_AUTO){
Log.e("CAMERA 2", "FLASH AUTO");
mPreviewCaptureRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
}
mFlashMode = flashMode;
if (mCameraCaptureSession != null) {
mCameraCaptureSession.close();
mCameraCaptureSession = null;
}
createCameraPreviewSession();
For some reason, CONTROL_AE_MODE_OFF would turn the whole preview black.
I tried looking in the docs for methods to update but haven't found anything.
Any tutorials or docs is much appreciated.

As mentioned by #cyborg86pl when switching flash modes you should not switch CONTROL_AE_MODE . Instead you can switch between FLASH_MODE´s. Here is a working example for my case:
when (currentFlashState) {
FlashState.AUTO -> {
previewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH)
}
FlashState.ON -> {
previewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON)
previewRequestBuilder.set(CaptureRequest.FLASH_MODE, CameraMetadata.FLASH_MODE_TORCH)
}
FlashState.OFF -> {
previewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON)
previewRequestBuilder.set(CaptureRequest.FLASH_MODE, CaptureRequest.FLASH_MODE_OFF)
}
}
previewRequest = previewRequestBuilder.build()
captureSession.setRepeatingRequest(previewRequest, captureCallback, backgroundHandler)

I don't know why your preview turn black, but you don't need to close capture session manually. From .close() method's docs:
Using createCaptureSession(List , CameraCaptureSession.StateCallback,
Handler) directly without closing is the recommended approach for
quickly switching to a new session, since unchanged target outputs can
be reused more efficiently.
So you can reuse existing CaptureRequest.Builder, set your changed value, build new PreviewRequest and just start new session with this new request, like this:
try {
// Change some capture settings
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON);
// Build new request (we can't just edit existing one, as it is immutable)
mPreviewRequest = mPreviewRequestBuilder.build();
// Set new repeating request with our changed one
mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback, mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
It will be much faster (almost without any visible freeze of preview).

What you want is disabling flash, not auto-exposure (AE), thus you want to use CONTROL_AE_MODE_ON rather than CONTROL_AE_MODE_OFF.
As mentioned in the documentation:
CONTROL_AE_MODE_ON
The camera device's autoexposure routine is active, with no flash control.

How to save Arrays and Strings together into one, Compact Package

I am trying to save some user data internally. Ideally, I would like to save
String[] text;
String name;
String file_name;
Together in one (for lack of a better term) package, and then use all saves name's with the other data to populate another activities listView, where I can load the saved information. Here is the code I am trying to use to save the information:
Button fileName;
fileName = (Button) findViewById(R.id.save_text);
fileName.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
outputStream = openFileOutput(file_name, Context.MODE_APPEND);
ObjectOutputStream phone_save = new ObjectOutputStream(outputStream);
phone_save.writeObject(name);
phone_save.writeObject(text);
Log.i("Save", "Files saved");
} catch (Exception e) {
e.printStackTrace();
}
}
});
Then this is the code that tries to get that saved information(for now I just have it trying to set the text of a text View, not a listView yet)
Button load;
TextView load_text
load = (Button) findViewById(R.id.load);
load.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
fin = openFileInput(file_name);
ObjectInputStream ois = new ObjectInputStream(fin);
String[] Loaded_Text = (String[]) ois.readObject();
ois.close();
load_text.setText(Html.fromHtml(Arrays.toString(Loaded_Text)));
} catch (Exception e) {
e.printStackTrace();
}
}
});
I am having a problem saving and loading the data, no log statement appears when I push the filename button, and nothing appears in the textView when I push the load Button. Essentially none of it works, and I have absolutely no clue how to fix it. I'm sure this code is a mess, but this is really my first time working with storage. Thanks everyone!

Posting as an answer you can accept.
Did you consider using SharedPreferences? I think that would be a lot simpler than writing and reading files. You store key-value pairs, so any piece of data needs a unique string to identify it.
prefs.putString("key1",stringValue);
prefs.putString("key2", anotherStringValue);
You would just need to convert your string array to and from a string.

You should consider implementing database support for your application. Database data is easier to maintain, in contrast to SharedPreferences. Here is a good tutorial that explains how to implement an SQLite database.

How can I delete a pre-existing image from storage before re-downloading using DownloadManager?

I am writing code for an Android app using Eclipse that is supposed to download an image from a URL (which is generated by the app, elsewhere in the code, using GPS information), then attach the newly downloaded image to an e-mail to be sent. I am able to, in general, accomplish this without much issue.
My problem is this: I only want one image downloaded by the app to be present in the device's external storage at any given time. Deleting the image after the email intent does not work, because because the app doesn't always call onStop or onDestroy when switching to another app to send the email. Time-sensitive deleting of the image will not work either, because I cannot assume that the user will send only one email from the app per hour. I want to give the user the freedom of sending as many of these emails (with one newly downloaded image, each) as they wish.
My current method (which works MOST of the time) is this: in the downloadFile method, simply check for the file's existence (I call it sensorMap.png), then delete it if it exists, before downloading a new one. This SHOULD ensure that there may be only one sensorMap.png image in external storage at any given time (EDIT: it does do this), and that when it comes time to attach the image to the email intent, there will be exactly one image ready to go. Instead, I see that sometimes a second sensorMap image is sometimes being downloaded into storage (i.e. "sensorMap-1.png"), OR the image cannot be attached to the email due to a "File size: 0 bytes" error, OR the image cannot be attached due to a "File does not exist" error. I am unsure what the difference between the latter two problems is. EDIT: Upon manually examining the contents of the directory I created, it seems that, as intended, I end up with only one image titled "sensorMap.png" at a time; it remains in the directory after the app closes, as expected. However, I still occasionally get the "File size: 0 bytes" message or the "File does not exist." message with no attached image, even though I see that the image DOES exist upon looking in directory afterwards. Other times, everything works just fine. It's rather bewildering.
In addition, there is an issue of the button which sends the email becoming unresponsive occasionally. Most of the time, it prompts the user to select an email client, as intended, but occasionally the button will LOOK as if clicked, but do nothing. When this happens, the logcat does not sense that the button was even clicked (I inserted a println statement to test it).
I am unsure of why my delete-before-download is not working flawlessly; the basic idea, at least, appears to be logically sound. Here is the code pertaining to my issue:
Code used to download file (in MainCountActivity.java):
//Function to download image given URL. Will use to attach image file to email.
public void downloadFile(String uRl) {
//delete existing file first so that only one sensorMap image exists in memory
//at any given time.
File file = new File(Environment.getExternalStorageDirectory()+"/SensorLocationImages");
File checkFile = new File(Environment.getExternalStorageDirectory()+"/SensorLocationImages/sensorMap.png");
if(checkFile.exists())
{
//debugging:
System.out.println("About to delete file!");
//deleteFiles(Environment.getExternalStorageDirectory()+"/SensorLocationImages");
checkFile.delete();
}
DownloadManager mgr = (DownloadManager) getActivity().getSystemService(Context.DOWNLOAD_SERVICE);
Uri downloadUri = Uri.parse(uRl);
DownloadManager.Request request = new DownloadManager.Request(
downloadUri);
request.setAllowedNetworkTypes(
DownloadManager.Request.NETWORK_WIFI
| DownloadManager.Request.NETWORK_MOBILE)
.setAllowedOverRoaming(false).setTitle("Sensor Location Map")
.setDescription("Pinpointed is the location from which the log file was sent.")
.setDestinationInExternalPublicDir("/SensorLocationImages", "sensorMap.png");
mgr.enqueue(request);
}
public Activity getActivity() //I wasn't sure if this would work, but it did. Or at least appears to.
{ return this; }
Method to send email (in MainCountActivity.java):
public void sendEmail(String toAddress, String ccAddress, String bccAddress, String subject, String body, String attachmentMimeType) throws Exception{
try {
Intent emailIntent = new Intent(Intent.ACTION_SEND_MULTIPLE);
emailIntent.setType(attachmentMimeType); //new
String sToAddress[] = { toAddress };
String sCCAddress[] = { ccAddress};
String sBCCAddress[] = { bccAddress };
emailIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
emailIntent.putExtra(Intent.EXTRA_EMAIL, sToAddress);
emailIntent.putExtra(android.content.Intent.EXTRA_CC, sCCAddress);
emailIntent.putExtra(android.content.Intent.EXTRA_BCC, sBCCAddress);
emailIntent.putExtra(Intent.EXTRA_SUBJECT, subject);
emailIntent.putExtra(Intent.EXTRA_TEXT, body);
//get URI of logfile
File tempFile = new File(Environment.getExternalStorageDirectory () + MainCountActivity.dirPath);
Uri uri = Uri.fromFile(tempFile);
//create URI arraylist and add first URI
ArrayList<Uri> uris = new ArrayList<Uri>();
uris.add(uri);
//get URI of map image and add to arraylist
//make sure it is there to attach
File file = new File(Environment.getExternalStorageDirectory()+"/SensorLocationImages");
do {
downloadFile(getMapLink());
//createDirectoryAndSaveFile(getBitmapFromURL(getMapLink()), "sensorMap.png");
} while (!file.exists());
uris.add(Uri.fromFile(new File(Environment
.getExternalStorageDirectory()
+ "/SensorLocationImages/sensorMap.png")));
//+ "/sdcard/SensorLocationImages/sensorMap.png")));
emailIntent.putParcelableArrayListExtra(Intent.EXTRA_STREAM, uris);
startActivity(emailIntent);
}
catch(Exception ex) {
ex.printStackTrace();
throw ex;
}
}
OnClick method, for my occasional button issue (In MaincountActivity.java):
public void onClick(View v){
switch(v.getId())
{
case R.id.textView1:
{
break;
}
case R.id.Reset:
{
//allowCounting will let the program know when to let it to count or not, depending if Start or Stop button are pressed.
logCount=0;
mCounter.setText("Total: 0");
mToggle.setChecked(false);
break;
}
/* case R.id.toggleButton:
{
break;
}*/
case R.id.SendEmail:
{
//for debugging purposes:
System.out.println("Email button being clicked!");
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
{
Toast.makeText(this, "GPS is enabled in your device", Toast.LENGTH_SHORT).show();
try {
sendEmail("","","","Sensor Log Info",getEmailBody(),"multipart/mixed");
} catch (Exception e) {
e.printStackTrace();
}
}
else
{
showGPSAlertForEmail();
}
break;
}
}
Basically, I really want to know why my delete-then-download method has not worked every time. Logcat errors have provided no insight. Thank you for your time.