Develop Reference

Android Q - Delete Media (Audio) File

I've been trying to get my app to be able to delete an audio file. However, after trying many possible solutions, I couldn't really find one that works.
Here is my solution so far:
public static void deleteFiles(List<Track> tracks, Context context,
final MutableLiveData<IntentSender> deletionIntentSenderLD){
final Uri AUDIO_URI = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
for(Track t : tracks){
try {
context.getContentResolver().delete(ContentUris
.withAppendedId(AUDIO_URI, t.getUriId()), null, null);
}catch (SecurityException securityException) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
if (securityException instanceof RecoverableSecurityException) {
deletionIntentSenderLD
.postValue(((RecoverableSecurityException) securityException)
.getUserAction().getActionIntent().getIntentSender());
} else
throw securityException;
} else
throw securityException;
}
}
}
When the try block fails a SecurityException is catch then the IntentSender is passed to the live data that is observed in a fragment:
audioViewModel.getDeletionIntentSenderLD().observe(getViewLifecycleOwner(),
intentSender -> {
try {
startIntentSenderForResult(intentSender, DELETE_PERMISSION_REQUEST,
null, 0 ,0, 0,
null);
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
});
I've tried implementing the onRequestPermissionResult() method but that doesn't do anything. I've also tried deleting the files using File file = new File(), however, due to the changes made to Android 10, I didn't expect it to work.

So after many Google searches, I've come to the conclusion that the best approach (to my knowledge) is to simply turn off scoped storage for Android Q (10).
Here, I'll provide two solutions. The first is the one where I turn it off and the second is the one where scope storage is still enable. However, a thing you should note is that the second solution is a little buggy, at times it actually does delete both the actual media file and updates the Media Store, but most times it simply deletes from the Media Store only. Obviously, this isn't a very good solution as on reboot your application would then load those files back in because the Media Store would scan for them.
Solution 1 - Turn off Scoped Storage
For this solution you can still target Android 11. All you have to do is go to the build.gradle file at the Module Level and set the compileSdkVersion and targetSdkVersion to 30.
After that, you go into the AndroidManifest.xml and have the uses-permission and application tag set up like this:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission
android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="29"
tools:ignore="ScopedStorage"/>
<application
android:requestLegacyExternalStorage="true"
...
After having done that, you could use the Content Resolver to delete the media file (and update the Media Store) and you do not have to worry about catching a security exception like its said in the Android docs. Your implementation for Android 11s delete operation should not be affected.
Solution-ish 2 - Turn on Scoped Storage
Firstly, in your manifest ensure that the WRITE_EXTERNAL_STORAGE permissions maxSdkVersion is set to 28. Also ensure that requestLegacyExternalStorage is set to false (don't think this is required). Then simply copy the code in my original post. You do not require a Live Data if you are doing the delete operation from your activity/fragment. But you should note that startIntentSenderForResult() requires an activity.
But as I mentioned before, I did experience some bugs with this. The most frustrating thing about this solution though is that it does not delete the actual file but instead deletes the entry from the Media Store. Maybe this has something to do with the fact that #blackapps mentioned, which is that you cannot bulk delete and I might have implemented it slightly wrong. Nevertheless, this is horrible for user experience if bulk deletion is impossible in Android 10.
The tutorials I followed for this are:
https://developer.android.com/training/data-storage/shared/media#remove-item
https://www.raywenderlich.com/9577211-scoped-storage-in-android-10-getting-started#toc-anchor-007
https://www.solutionanalysts.com/blog/scoped-storage-in-android-10/
Side Note - Delete on Android 11
To delete on Android 11 you just need to call createDeleteRequest() which should return a PendingIntent. From this PendingIntent you could get the IntentSender by using getIntentSender. Pass this intent sender to the activity/fragment then call startIntentSenderForResult() in your activity/fragment. This pops up a dialog to the user asking them if the application can delete a file. If the user gives permission the system goes ahead and deletes the file and updates the Media Store.
Side Side Note - Scoped Storage, Android 10 and Future
From everything I've seen, it seems to suggest that scoped storage is only enforced in Android 11 but I'm not entirely sure if the legacy option would still be available in Android 10 indefinitely. But I would have to do more research on this...

Android Studio #androidx.annotation.NonNull error when onRequestPermissionResult is called inside MapFragment

Hello I am still fairly new to this, so please help me understand why I am having this error. I have tried many solutions, so I'm just going to list everything I've done since I can't seem to understand why this is happening.
I created a project that integrates GoogleMaps at min SDK 21 to target/compile at SDK 28. I did call the permissions needed inside the Manifesto.
I created a file that extends the MapFragment class and everything seems to be working fine. I am able to check and request permission for the user's location (the box does show up), but when I called the onRequestPermissionResult method it is shown differently and gives me an error saying "error: cannot find symbol class NonNull":
#Override
public void onRequestPermissionsResult(int requestCode, #androidx.annotation.NonNull String[] permissions, #androidx.annotation.NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
In my other Fragment (android.support.v4.app) classes the #androidx.annotation.NonNull is #NonNull instead. I first thought maybe I needed to add implementation 'com.android.support:support-annotations:28.0.0' to the build.gradle, but that wasn't the case. I then tried to just replace the #androidx.annotation.NonNull with #NonNull which made the error go away, but whenever I clicked allow or deny it wasn't hitting the onRequestPermissionResult method.
I created a method that checks for a permission, but it won't let me use requestPermission on its own without checking if the build is greater or equal to SDK 23, but my min SDK is 21. So instead I just checked if the build is greater or equal to 21 and used ActivityCompat to get the requestPermission method and it works. It will check and ask for permission, so I'm thinking maybe the onRequestPermissionResult only works in the MainActivity which is what I don't want. I want to be able to call a method after checking if the request was granted inside the MapFragment. Is it because MapFragment isn't supported with android.support.v4.app? It looks like this:
private boolean checkAskPermission(int requestCode, String permissionString){
if(Build.VERSION.SDK_INT >= 21){
int permission = ContextCompat.checkSelfPermission(mContext, permissionString);
if(permission!=PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(getActivity(), new String[]{permissionString}, requestCode);
return false;
}
}
return true;
}
At this point I don't know what else to try. I thought maybe I wasn't checking the permission correctly inside onRequestPermissionResult when I change #androidx.annotation.NonNull to #NonNull to be able to use it, but the method doesn't hit when I use a break on it.
Please leave detail responses, so I can fully understand my problem. I have been stuck on this for a day.
Edit: Solution
private boolean checkAskPermission(int requestCode, String permissionString){
if(Build.VERSION.SDK_INT >= 23){
int permission = ContextCompat.checkSelfPermission(mContext, permissionString);
if(permission!=PackageManager.PERMISSION_GRANTED){
requestPermissions(new String[]{permissionString}, requestCode);
return false;
}
}
return true;
}
and just changed the #androidx.annotation.NonNull to #NonNull and now it hits the method.
Thanks to Eugene for clearing up SDK permissions. Only SDK 23 and higher require permission.

import that annotation class:
import androidx.annotation.NonNull;
which is either coming from this dependency:
implementation "androidx.annotation:annotation:1.0.0"
or from this dependency, in case not yet using androidx:
implementation "com.android.support:support-annotations:28.0.0"
then you can use it as usual:
#NonNull

The only work-around that I found useful was to fore-go the react-native run-android command and manually go into the react-native library (for me: ProjectHome/node_modules/ModuleIWantToChange/android/src/main/java/FileToChange.java) that was importing androidx.annotation.NonNull, changing that dependency to android.support.annotation.NonNull and then making sure to compile with the com.android.support:support-annotations under "dependencies" in that node_module's "android/build.gradle" file. In my case, I'm using version "com.android.support:support-annotations:25.3.1". You'll have to make sure that you have the version you call out here. Look at what you have installed with Android Studio under $ANDROID_HOME/extras/android/m2repository/com/android/support/support-annotations.
Then, instead of react-native run-android, I moved to the android directory under the project's home directory and ran sudo ./gradlew --stacktrace installDebug (stacktrace is optional) to build and install the apk on my emulator/device.
This might not work for everyone, but it was a tolerable fix in my case.

[...] but the method doesn't hit when I use a break on it.
[...] used ActivityCompat to get the requestPermission [...]
You're in a fragment. Don't ask the activity for permissions. If you ask the fragment you also get callback in the fragment.
requestPermissions(new String[]{permissionString}, requestCode);
Runtime permissions were introduced in API 23 (that's why the method is only available since API 23). Fix your condition. Before that having the permission declared in manifest is enough.
Off-topic: Platform fragments have been deprecated. Use support fragments instead. Extend SupportMapFragment.
#androidx.annotation.NonNull cannot be found because you don't use AndroidX in your project. You can use whatever other #NonNull annotation is available (either from the SDK or from the support library).

detector.isOperational() always false on android

I'm using the new google plays service: Barcode detector, for this porposue I'm following this tutorial : https://search-codelabs.appspot.com/codelabs/bar-codes
But when I run the application on my real device(Asus Nexus 7), the text view of the app always is showing me "Couldn't set up the detector" and i don't know how to make it work >< ...
Here some code for fast debugging:
public class DecoderBar extends Activity implements View.OnClickListener{
private TextView txt;
private ImageView img;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_decoder);
Button b = (Button) findViewById(R.id.button);
txt = (TextView) findViewById(R.id.txtContent);
img = (ImageView) findViewById(R.id.imgview);
b.setOnClickListener(this);
}
// [...]
#Override
public void onClick(View v) {
Bitmap myBitmap = BitmapFactory.decodeResource(getApplicationContext().getResources(),R.drawable.popi);
img.setImageBitmap(myBitmap);
BarcodeDetector detector = new BarcodeDetector.Builder(getApplicationContext())
.setBarcodeFormats(Barcode.DATA_MATRIX | Barcode.QR_CODE)
.build();
if(!detector.isOperational()){
// Always show this message, so, never is operational!
txt.setText("Could not set up the detector!");
return;
}
Frame frame = new Frame.Builder().setBitmap(myBitmap).build();
SparseArray<Barcode> barcodes = detector.detect(frame);
Barcode thisCode = barcodes.valueAt(0);
txt.setText(thisCode.rawValue);
}
}

It looks like the first time barcode detector is used on each device, some download is done by Google Play Services. Here is the link:
https://developers.google.com/vision/multi-tracker-tutorial
And this is the excerpt:
The first time that an app using barcode and/or face APIs is installed
on a device, GMS will download a libraries to the device in order to
do barcode and face detection. Usually this is done by the installer
before the app is run for the first time.

I had this problem now. You can't update the Google Play Services. After I used the same as on the tutorial it works.
compile 'com.google.android.gms:play-services:7.8+'

Here is what was my case.
I was using BarcodeDetector for decoding QR codes from imported images. On 4 my testing devices it was working fine. On one was not reading anything from bitmap. I thought this might be incompatibility with android 5.0 but this was not the case. After hours of investigation I finally noticed that detector.isOperational(); returns false. The reason was:
The first time that an app using barcode and/or face APIs is installed on a device, GMS will download a libraries to the device in order to do barcode and face detection. Usually this is done by the installer before the app is run for the first time.
I had wi-fi off on that testing device. After turning it on and relaunching app, detector became operational and started decoding bitmaps.

To use the API, it's necessary to have internet connection, I had connection to my ADSL but not resolved DNS. Fixing that problem make my app works

Sometimes detector dependencies are downloaded when the app runs for the first time and not when the app installs. I too faced the same issue, the problem is either your network connection is weak or you don't have enough storage for download say 10% of the total space though it does not take that much space but downloads from Google Play Services does require good amount of storage and don't forget to clear cache(Simple check try to update any application from playstore). Refer this Github thread for more information.

Check your storage! make sure it is over 10%
That fixed my problem, and I answered it here too...
https://stackoverflow.com/a/43229272/6914806

you must not forget this:
add this to your AndroidManifest.xml
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<meta-data
android:name="com.google.android.gms.version"
android:value="#integer/google_play_services_version" />
<meta-data
android:name="com.google.android.gms.vision.DEPENDENCIES"
android:value="ocr"/>

App crashing after update FragmentList from loader using support library

I have a loader that uses the Support Library v4, it is being used to carry the loading of a ListView in an Activity that contains two fragments, one containing the ListView (being it an extension of ListFragment) and the other carrying a button (which can be clicked while the loader is doing the work).
The implementation is pretty similar to the one available at the Android documentation of the AsyncTaskLoader, which is also creating a ListView trough the loader, with the exception of the monitoring part, where my implementation does not need the monitoring of changes: http://developer.android.com/reference/android/content/AsyncTaskLoader.html
As the app has support to API level 8, I am using the FragmentActivity::getSupportLoaderManager method to start the loader as advised in the documentation in order to keep the support.
http://developer.android.com/reference/android/support/v4/app/FragmentActivity.html
When using this class as opposed to new platform's built-in fragment and loader support, you must use the getSupportFragmentManager() and getSupportLoaderManager() methods respectively to access those features.
Being the loader started from the Fragment, I had to use the ListFragment::getActivity method to call the method FragmentActivity::getSupportLoaderManager, resulting in the following code being used to start the loader:
getActivity().getSupportLoaderManager().initLoader(0, null, this).forceLoad();
The app is running fine with APIs higher than 8, but on level 8 it is crashing when the loader tries to renders the list on UI after loading (Loader::onLoadFinished method).
Debugging I found that it is crashing at the moment that the ArrayAdapter<>::addAll method is being called on the adapter, which confirms that the problem is on the rendering of the UI. At that moment, the app is thrown to the SamplingProfilerIntegration class where something related to a snapshot is trying to be done at a static part of the class:
/** Whether or not a snapshot is being persisted. */
private static final AtomicBoolean pending = new AtomicBoolean(false);
static {
samplingProfilerMilliseconds = SystemProperties.getInt("persist.sys.profiler_ms", 0);
samplingProfilerDepth = SystemProperties.getInt("persist.sys.profiler_depth", 4);
if (samplingProfilerMilliseconds > 0) {
File dir = new File(SNAPSHOT_DIR);
dir.mkdirs();
// the directory needs to be writable to anybody to allow file writing
dir.setWritable(true, false);
// the directory needs to be executable to anybody to allow file creation
dir.setExecutable(true, false);
if (dir.isDirectory()) {
snapshotWriter = Executors.newSingleThreadExecutor(new ThreadFactory() {
public Thread newThread(Runnable r) {
return new Thread(r, TAG);
}
});
enabled = true;
Log.i(TAG, "Profiling enabled. Sampling interval ms: "
+ samplingProfilerMilliseconds);
} else {
snapshotWriter = null;
enabled = true;
Log.w(TAG, "Profiling setup failed. Could not create " + SNAPSHOT_DIR);
}
} else {
snapshotWriter = null;
enabled = false;
Log.i(TAG, "Profiling disabled.");
}
}
It could be related to the specific behavior of the UI rendering on prior to Honeycomb versions as stated in the documentation, but I can not think of what.
http://developer.android.com/reference/android/support/v4/app/FragmentActivity.html
Prior to Honeycomb (3.0), an activity's state was saved before pausing. Fragments are a significant amount of new state, and dynamic enough that one often wants them to change between pausing and stopping. These classes throw an exception if you try to change the fragment state after it has been saved, to avoid accidental loss of UI state. However this is too restrictive prior to Honeycomb, where the state is saved before pausing. To address this, when running on platforms prior to Honeycomb an exception will not be thrown if you change fragments between the state save and the activity being stopped. This means that in some cases if the activity is restored from its last saved state, this may be a snapshot slightly before what the user last saw.

I found that the support libraries v4 and v7, which are the being imported to the project, does not support the method ArrayAdapter<>::addAll() and this was making the app crash.
This question is related to this issue and the solution presented was suitable to address my problem:
ListViews - how to use ArrayAdapter.addAll() function before API 11?
So, the solution was to implement my own version of the ArrayAdapter class, so that the prior to Honeycomb versions of Android could use it.

How does Facebook add badge numbers on app icon in Android?

I know there are several Qs here that ask if its possible to add badges to an android app and they all end up with a NO answer...
But somehow the latest Facebook beta version for Android seems to do something which at least look like a badge even if it is not technically exactly that.
In that post one of the commenters says that it is somehow related to TouchWiz.
And also here they mention it as a feature of the "S3 TouchWiz Jelly Bean Addon".
I still would appreciate information on how does this can be done and if there is some API for this that I can use in my own app (when running in an appropriate environment - i.e. the same device where FB demonstrates this behavior) ?

Hi you can use this lib simply.
Support : Sony,Samsung,LG,HTC,Xiaomi,ASUS,ADW,APEX,NOVA,Huawei,ZUK,OPPO
ShortcutBadger
Add :
int badgeCount = 1;
ShortcutBadger.applyCount(context, badgeCount);
Remove :
ShortcutBadger.applyCount(context, 0);

I have figured out how this is done for Sony devices.
I've blogged about it here. I've also posted a seperate SO question about this here.
Sony devices use a class named BadgeReciever.
Declare the com.sonyericsson.home.permission.BROADCAST_BADGE permission in your manifest file:
Broadcast an Intent to the BadgeReceiver:
Intent intent = new Intent();
intent.setAction("com.sonyericsson.home.action.UPDATE_BADGE");
intent.putExtra("com.sonyericsson.home.intent.extra.badge.ACTIVITY_NAME", "com.yourdomain.yourapp.MainActivity");
intent.putExtra("com.sonyericsson.home.intent.extra.badge.SHOW_MESSAGE", true);
intent.putExtra("com.sonyericsson.home.intent.extra.badge.MESSAGE", "99");
intent.putExtra("com.sonyericsson.home.intent.extra.badge.PACKAGE_NAME", "com.yourdomain.yourapp");
sendBroadcast(intent);
Done. Once this Intent is broadcast the launcher should show a badge on your application icon.
To remove the badge again, simply send a new broadcast, this time with SHOW_MESSAGE set to false:
intent.putExtra("com.sonyericsson.home.intent.extra.badge.SHOW_MESSAGE", false);
I've excluded details on how I found this to keep the answer short, but it's all available in the blog. Might be an interesting read for someone.

There is not a standard way to achieve this; Many makers such as Sony or Samsung have implemented it in their own Android customization.
For example in Samsung, you have to broadcast an intent with BADGE_COUNT_UPDATE action, let MainActivity be your main activity class and count be the number you want to display in your app icon, note that 0 will hide the badge:
Intent intent = new Intent("android.intent.action.BADGE_COUNT_UPDATE");
intent.putExtra("badge_count", count);
intent.putExtra("badge_count_package_name", context.getPackageName());
intent.putExtra("badge_count_class_name", MainActivity.class.getName());
context.sendBroadcast(intent);
Sony devices uses "com.sonyericsson.home.action.UPDATE_BADGE" action with their custom extras as #Marcus Answered, so you have to add "com.sonyericsson.home.permission.BROADCAST_BADGE" permission to your app manifest and:
Intent intent = new Intent("com.sonyericsson.home.action.UPDATE_BADGE");
intent.putExtra("com.sonyericsson.home.intent.extra.badge.ACTIVITY_NAME", MainActivity.class.getName());
intent.putExtra("com.sonyericsson.home.intent.extra.badge.SHOW_MESSAGE", true);
intent.putExtra("com.sonyericsson.home.intent.extra.badge.MESSAGE", String.valueOf(count));
intent.putExtra("com.sonyericsson.home.intent.extra.badge.PACKAGE_NAME", context.getPackageName());
context.sendBroadcast(intent);
Note: it's desirable to query your app's data (context.getPackageName(), MainActivity.class.getName()) rather than hardcode it just in case you do some refactoring in the future.

But somehow the latest Facebook beta version for android does just that...
Not according to the forum thread that contains the screenshot that you linked to. Quoting vakama94:
Well, that's actually TouchWiz and not just the app. I have a Galaxy S II running JellyBean 4.1.2 and it makes the same thing but with some other applications
Whether Samsung has a public API to allow apps to publish numbers to be used as badges, I cannot say. This could be something that they did privately with a few firms.
You are welcome to provide evidence of seeing these badges on a stock Android home screen, such as one of the Nexus series devices.

I answer to this assuming that some flutter dev can search this...
In Flutter, you can achieve this by using
Flutter app badger library.
It is as simple as
FlutterAppBadger.updateBadgeCount(1); // show
FlutterAppBadger.removeBadge(); // hide