Develop Reference

DocumentsUI shows "Anonymous" application when requesting access to directory

One user reported that my app fails to request directory access when selecting a folder via the ACTION_OPEN_DOCUMENT_TREE intent.
For some reason it does not show my application, instead "Anonymous":
Translated: "Allow Anonymous to access files in Camera. This will let Anonymous access current and future content stored in Camera".
The user has a MIUI 12 with Android 11 on a Mi Note 10 lite.
I have the same just with a Mi Note 10, no issues ofc.
Checked the Android source code:
https://android.googlesource.com/platform/packages/apps/DocumentsUI/+/refs/heads/master/src/com/android/documentsui/picker/ConfirmFragment.java#82
case TYPE_OEPN_TREE:
final Uri treeUri = mTarget.getTreeDocumentUri();
final BaseActivity activity = (BaseActivity) getActivity();
final String target = activity.getCurrentTitle();
final String text = getString(R.string.open_tree_dialog_title,
**getCallingAppName**(getActivity()), target);
message = getString(R.string.open_tree_dialog_message,
**getCallingAppName**(getActivity()), target);
builder.setTitle(text);
builder.setMessage(message);
builder.setPositiveButton(
R.string.allow,
(DialogInterface dialog, int id) -> {
pickResult.increaseActionCount();
mActions.finishPicking(treeUri);
});
break;
#NonNull
public static String getCallingAppName(Activity activity) {
final String anonymous = activity.getString(R.string.anonymous_application);
final String packageName = getCallingPackageName(activity);
if (TextUtils.isEmpty(packageName)) {
return anonymous;
}
final PackageManager pm = activity.getPackageManager();
ApplicationInfo ai;
try {
ai = pm.getApplicationInfo(packageName, 0);
} catch (final PackageManager.NameNotFoundException e) {
return anonymous;
}
CharSequence result = pm.getApplicationLabel(ai);
return TextUtils.isEmpty(result) ? anonymous : result.toString();
}
public static String getCallingPackageName(Activity activity) {
String callingPackage = activity.getCallingPackage();
// System apps can set the calling package name using an extra.
try {
ApplicationInfo info =
activity.getPackageManager().getApplicationInfo(callingPackage, 0);
if (isSystemApp(info) || isUpdatedSystemApp(info)) {
final String extra = activity.getIntent().getStringExtra(
Intent.EXTRA_PACKAGE_NAME);
if (extra != null && !TextUtils.isEmpty(extra)) {
callingPackage = extra;
}
}
} catch (NameNotFoundException e) {
// Couldn't lookup calling package info. This isn't really
// gonna happen, given that we're getting the name of the
// calling package from trusty old Activity.getCallingPackage.
// For that reason, we ignore this exception.
}
return callingPackage;
}
...and it seems that for whatever reason my packagename isn't found. How can can happen?
Asked him to install one of my other apps, and it happens there as well.
Asked him then to install another app from the playstore (FX File Explorer) and there it does not happen.
So it is specific to his device and my app.

So it turned out that this user having that issue turned off the MIUI Optimizations in the developer settings.

Bug report: συσκευη, εκδοση miui, Play store install (alpha 1021). It was impossible to specify a b i o s file or specify a game image directory in when MIUI optimizations are off. Turning them back on fixed the issue and directories are scanned normally. Also on the popup to allow folder access the app displays as "Anonymous" instead of AetherSX2 on my system. Some developer was talking about having the same issue here.

PackageManager getChangedPackages always return NULL

In my app I need to monitorize recently added or updated packages, but since Oreo this is a hard task.
To do it I have a service that runs every X time to detect the new installed/updated apps.
The main core of this service is to call the getChangedPackages function from the PackageManager, but this function always returns null, even if I install or update any app from or not from the Play Store in the interval between two consequtive calls to getChangedPackages.
https://developer.android.com/reference/android/content/pm/PackageManager.html#getChangedPackages(int)
I need to request any permission to call this function? Is the getChangedPackages buggy?
private void _doProcess()
{
try
{
PackageManager package_manager = getPackageManager();
int sequence_number = ApplicationPreferences.getInteger(this, GET_CHANGED_PACKAGES_SEQUENCE_NUMBER_KEY, 0);
ChangedPackages changed_packages = package_manager.getChangedPackages(sequence_number);
LogUtilities.show(this, String.format("Retrieve recently apps installs/updates using sequence number %d returns %s", sequence_number, changed_packages == null ? "null" : "a not null object"));
if (changed_packages == null) changed_packages = package_manager.getChangedPackages(0);
LogUtilities.show(this, String.format("Retrieve recently apps installs/updates using sequence number %d returns %s", sequence_number, changed_packages == null ? "null" : "a not null object"));
if (changed_packages != null)
{
List<String> packages_names = changed_packages.getPackageNames();
LogUtilities.show(this, String.format("%d recently installed/updated apps", packages_names == null ? 0 : packages_names.size()));
if (packages_names != null) for (String package_name : packages_names) PackagesUpdatedReceiver.doProcessPackageUpdate(this, new Intent(isNewInstall(package_manager, package_name) ? Intent.ACTION_PACKAGE_ADDED : Intent.ACTION_PACKAGE_REPLACED).setData(Uri.parse(String.format("package:%s", package_name))));
LogUtilities.show(this, String.format("Storing %s is the sequence number for next iteration", changed_packages.getSequenceNumber()));
ApplicationPreferences.putInteger(this, GET_CHANGED_PACKAGES_SEQUENCE_NUMBER_KEY, changed_packages.getSequenceNumber());
}
else
{
LogUtilities.show(this, String.format("Storing %s is the sequence number for next iteration", sequence_number + 1));
ApplicationPreferences.putInteger(this, GET_CHANGED_PACKAGES_SEQUENCE_NUMBER_KEY, sequence_number + 1);
}
}
catch (Exception e)
{
LogUtilities.show(this, e);
}
}

My experimental results so far have shown that this PackageManager API method getChangedPackages() is not reliable: quite often the returned ChangedPackages value contains many unchanged packages. So I’ve decided to implement a similar feature in a class called PackageUtils, as shown below. The idea is to poll for all the installed packages, as shown in method getInstalledPackageNames() below, and compare the string list with a previously saved one. This comparison boils down to comparing 2 string lists, as shown in method operate2StringLists() below. To get a set of removed packages, use GET_1_MINUS_2_OR_REMOVED as operation. To get a set of added packages, use GET_2_MINUS_1_OR_ADDED as operation.
public class PackageUtils {
public static final int GET_1_MINUS_2_OR_REMOVED = 0;
public static final int GET_2_MINUS_1_OR_ADDED = 1;
// Get all the installed package names
public static List<String> getInstalledPackageNames(Context context) {
List<String> installedPackageNames = new ArrayList<>();
try {
PackageManager packageManager = context.getPackageManager();
List<ApplicationInfo> appInfoList = packageManager.getInstalledApplications(PackageManager.GET_META_DATA);
for (ApplicationInfo appInfo : appInfoList) {
installedPackageNames.add(appInfo.packageName);
}
} catch (Exception e) {
e.printStackTrace();
}
return installedPackageNames;
}
// Compare 2 string lists and return differences.
public static Set<String> operate2StringLists(List<String> pkgList1, List<String> pkgList2, int operation) {
Set<String> result = null;
Set<String> pkgSet1 = new HashSet<String>(pkgList1);
Set<String> pkgSet2 = new HashSet<String>(pkgList2);
switch (operation) {
case GET_1_MINUS_2_OR_REMOVED:
pkgSet1.removeAll(pkgSet2);
result = pkgSet1;
break;
case GET_2_MINUS_1_OR_ADDED:
pkgSet2.removeAll(pkgSet1);
result = pkgSet2;
break;
default:
break;
}
return result;
}
}
The code has been tested on an Android Oreo device. It can reliably detect all added and removed packages between 2 time instances. However, it can’t detect updated packages in-between.

Finally got it. You have to create a variable called sequenceNumber, and update it every time you query changed packages.
private static int sequenceNumber = 0;
...
PackageManager pm = getContext().getPackageManager();
ChangedPackages changedPackages = pm.getChangedPackages(sequenceNumber);
if(changedPackages != null)
sequenceNumber = changedPackages.getSequenceNumber();

Open android app from webView inside another android app

In my app there is a WebView to which I load a website from server.
There are two cases:
On the loaded website there is a button which should lead to an another app. I know it can be handled like this:
Click me
but this doesn't work in the WebView (only in a standalone browser)! I tried to handle it in shouldOverrideUrlLoading and redirect to an external browser with Intent, but the URI with "intent://" URL is not recognised and cannot be opened.
The link I get from server is the 'intent' link.
The behaviour in both cases should be the same: if app is installed open the app, if not open Google Play do download the app.
Is there any way to do this?

I'm not sure if this is the best option, but I handeled it similarily to what #vineetv suggested. This method is called inside shouldOverrideUrlLoading():
private void handleNewUrl(String url) {
Uri uri = Uri.parse(url);
if (uri.getScheme().equals("http") || uri.getScheme().equals("https"))
openExternalWebsite(url);
else if (uri.getScheme().equals("intent")) {
String appPackage = getAppPackageFromUri(uri);
if (appPackage != null) {
PackageManager manager = getContext().getPackageManager();
Intent appIntent = manager.getLaunchIntentForPackage(appPackage);
if (appIntent != null) {
getActivity().startActivity(appIntent);
} else {
openExternalWebsite("https://play.google.com/store/apps/details?id=" + appPackage);
}
}
}
}
private String getAppPackageFromUri(Uri intentUri) {
Pattern pattern = Pattern.compile("package=(.*?);");
Matcher matcher = pattern.matcher(intentUri.getFragment());
if (matcher.find())
return matcher.group(1);
return null;
}
private void openExternalWebsite(String url) {
Intent webeIntent = new Intent(Intent.ACTION_VIEW);
webeIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
webeIntent.setData(Uri.parse(url));
getActivity().startActivity(webeIntent);
}
It seems, to work. But if you have a better solution, let me know!

How can I attach an image to a "Direct Message" in twitter Android?

I programmed an app that can send a message to twitter with an image attached. It works! I tested it on several devices and asked other people to do the same. It even works for a Direct Message when a twitter friend is selected. However, it does not work when "Direct Message" is selected. This forces the user to select a friend directly instead of selecting him via "Direct Message" (which is really strange) otherwise the picture is not attached. Just have a look at the screenshot:
Here is my Xamarin Android programming code. Let me know how to fix it. Currently, all options work, even selecting my friend but not "Direct Message". I also need to tell that I do not have any issue with the twitter text I expect to see in the tweet.
public bool TweetImage(Bitmap imageToTweet)
{
var messageIntent = context.FindMessageIntent(this.twitterConstants.PackageName);
if (messageIntent == null)
{
return false;
}
string outputFileBMP = SaveBitmap(imageToTweet);
context.Tweet(messageIntent, outputFileBMP, this.twitterConstants.DefaultTwitterText, this.twitterConstants.ChooserMessage);
return true;
}
and
public static Intent FindMessageIntent(this ContextWrapper contextWrapper, params string[] packageNames)
{
Intent wantedIntent = new Intent();
wantedIntent.SetType("text/plain");
var resolveInfos = contextWrapper.PackageManager.QueryIntentActivities(wantedIntent, PackageInfoFlags.MatchDefaultOnly);
var result = (from r in resolveInfos
from p in packageNames
where p == r.ActivityInfo.PackageName
select p).FirstOrDefault();
if (result != null)
{
wantedIntent.SetPackage(result);
return wantedIntent;
}
return null;
}
and
public static void Tweet(this ContextWrapper contextWrapper, Intent messageIntent, string filePath = null, string message = null, string chooserMessage = null)
{
if (filePath != null)
{
using (var file = new Java.IO.File(filePath))
{
messageIntent.PutExtra(Intent.ExtraStream, Android.Net.Uri.FromFile(file));
}
}
if (message != null)
{
messageIntent.PutExtra(Intent.ExtraText, message);
}
if (chooserMessage != null)
{
using (var chooser = Intent.CreateChooser(messageIntent, chooserMessage))
{
contextWrapper.StartActivity(chooser);
}
return;
}
contextWrapper.StartActivity(messageIntent);
}
Please note that I am using Android and need a solution based on Android (intent based).

Sadly, Twitter don't provide API access for uploading images via DM.
If you are able to use Twitter's private API, you should be able to attach a media_id to your DM. But other than that, you're out of luck.
Sorry.

Integrating and working with .pkpass passes in Xamarin Android app

I'm developing a Xamarin Android app and I need the ability to be able to work with Passes (PassKit passes for example (JSON)). I need to be able to list all the passes in a ListVew and be able to open and display the pass. Also be able to save them to a wallet such as PassWallet or Pass2u. I don't need the ability to create them, just view them, and save them to a wallet or discard them.
There seems to be an example Xamarin iOS app which does exactly what i need here but of course I need to be able to do this in Xamarin Android.
I've been researching this for hours but don't know how to achieve what i need. JSON.net seems the way to go to read the passes, but that's as far as I've managed to get. Some examples would be great. Can anybody help?

To add the pass into PassWallet you can use the following:
private static boolean launchPassWallet(Context applicationContext, Uri uri, boolean launchGooglePlay) {
if (null != applicationContext) {
PackageManager packageManager = applicationContext.getPackageManager();
if (null != packageManager) {
final String strPackageName = "com.attidomobile.passwallet";
Intent startIntent = new Intent();
startIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startIntent.setAction(Intent.ACTION_VIEW);
Intent passWalletLaunchIntent = packageManager
.getLaunchIntentForPackage(strPackageName);
if (null == passWalletLaunchIntent) {
// PassWallet isn't installed, open Google Play:
if (launchGooglePlay) {
String strReferrer = "";
try {
strReferrer = "&referrer=" + URLEncoder.encode(uri.toString(), "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
strReferrer = "";
}
try {
startIntent.setData(Uri.parse("market://details?id=" + strPackageName + strReferrer));
applicationContext.startActivity(startIntent);
} catch (android.content.ActivityNotFoundException anfe) {
// Google Play not installed, open via website
startIntent.setData(Uri.parse("http://play.google.com/store/apps/details?id=" + strPackageName + strReferrer));
applicationContext.startActivity(startIntent);
}
}
} else {
final String strClassName = "com.attidomobile.passwallet.activity.TicketDetailActivity";
startIntent.setClassName(strPackageName, strClassName);
startIntent.addCategory(Intent.CATEGORY_BROWSABLE);
startIntent.setDataAndType(uri, "application/vnd.apple.pkpass");
applicationContext.startActivity(startIntent);
return true;
}
}
}
return false;
}
And an example call is:
launchPassWallet(getApplicationContext(),Uri.parse("http://test.attidomobile.com/PassWallet/Passes/AttidoMobile.pkpass"), true);
You can also use a file:// URL if you have the file locally.
To display them in the list, you'd need to unzip the .pkpass file and then parse the JSON for the relevant fields.