Develop Reference

Broadcast receiver is not working - why so?

I'm studying Android.
I try to implement a Custom static Broadcast Receiver but it is not working.
I search for some issue from Google but I can't find something to solve this.
I work on Android 7.0 Min Level 24 Target Level 28
In fact, MyStaticReceiver isn't launching when I start the Activity (no log)
MyDynamicReceiver work perfectly
Do you have a solution?
AndroidManifest.xml :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="test.receiver">
<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">
<activity android:name="test.receiver.MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver
android:name=".MyStaticReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="#string/StaticAction" />
</intent-filter>
</receiver>
</application>
</manifest>
MainActivity.java :
public class MainActivity extends Activity {
public final static boolean Debug = true;
public final static String TAG = "TagDebug";
private MyDynamicReceiver dynamicReceiver;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ComponentName receiver = new ComponentName(this, MyStaticReceiver.class);
PackageManager pm = this.getPackageManager();
pm.setComponentEnabledSetting(receiver,
PackageManager.COMPONENT_ENABLED_STATE_ENABLED,
PackageManager.DONT_KILL_APP);
}
#Override
protected void onResume() {
super.onResume();
if (Debug) Log.i(TAG, "MainActivity:onResume");
configureDynamicReceiver();
}
#Override
protected void onDestroy(){
super.onDestroy();
if (Debug) Log.i(TAG, "MainActivity:onDestroy");
unregisterReceiver(dynamicReceiver);
}
public void onClickButton(View v) {
if (Debug) Log.i(TAG, "MainActivity:onClickButton");
Intent staticIntent = new Intent();
staticIntent.setAction(getString(R.string.StaticAction));
sendBroadcast(staticIntent);
Intent dynamicIntent = new Intent();
dynamicIntent.setAction(getString(R.string.DynamicAction));
sendBroadcast(dynamicIntent);
}
public void configureDynamicReceiver() {
if( dynamicReceiver == null ) {
dynamicReceiver = new MyDynamicReceiver();
}
IntentFilter filter = new IntentFilter(getString(R.string.DynamicAction));
registerReceiver(dynamicReceiver, filter);
}
}
MyStaticReceiver.java (MyDynamicReceiver is the same ...)
public class MyStaticReceiver extends BroadcastReceiver {
public final static boolean Debug = true;
public final static String TAG = "TagDebug";
public MyStaticReceiver() {
if (Debug) Log.i(TAG, "MyStaticReceiver");
}
#Override
public void onReceive(Context context, Intent intent) {
if (Debug) Log.i(TAG, "MyStaticReceiver:onReceive");
}
}

You are actually sending an implicit broadcast, therefore the receiver declared in the manifest will not work.
If your app targets Android 8.0 (API level 26) or higher, you cannot use the manifest
to declare a receiver for most implicit broadcasts (broadcasts that
don't target your app specifically). You can still use a
context-registered receiver when the user is actively using your app. Link
You don't face any issue with MyDynamicReceiver because it is context-registered receiver.
But to make it work for MyStaticReceiver, you can try sending an explicit broadcast by passing the component name in the constructor of the Intent.
Intent staticIntent = new Intent(this, MyStaticReceiver.class);
staticIntent.setAction(getString(R.string.StaticAction));
sendBroadcast(staticIntent);

How can I programmatically hide app icon after the installation in android , then access thru secret code like *#*#numbers*#*#?

I am new to android programming and I want my app to hide application icon after installation. I will use the code for my thesis. Thank you.

First, you have to make a receiver like this..
public class MyReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
String phoneNubmer = intent.getStringExtra(Intent.EXTRA_PHONE_NUMBER);
if (LAUNCHER_NUMBER.equals("**11**")) {
PackageManager p = context.getPackageManager();
ComponentName componentName = new ComponentName(context, MainActivity.class);
p.setComponentEnabledSetting(componentName, PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);
} else if (LAUNCHER_NUMBER.equals("**22**")) {
ComponentName componentToEnable = new ComponentName(getApplicationContext(), MainActivity.class);
PackageManager pm = getApplicationContext().getPackageManager();
pm.setComponentEnabledSetting(componentToEnable, PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP);
}
}
}
Add this Permission to manifest.
<uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS" />
Register it to manifest file.
<receiver android:name=".MyReceiver" >
<intent-filter>
<action android:name="android.intent.action.NEW_OUTGOING_CALL" />
</intent-filter>
</receiver>
Enjoy Coding...

How to open an app from another app in android?

I have an application named as "App" and another application named as "App1", I have a button in "App" when I click that button I want to open "App1", for this I am using Intent but it does not open "App1".Please help
here is my code for button in "App":-
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.app);
init();
}
public void init(){
mTranslucentBtn = (Button) findViewById(R.id.button);
mTranslucentBtn.setAlpha(0.7f);
mTranslucentBtn.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v){//calling an activity using <intent-filter> action name
startNewActivity(MainActivity.this,"com.example.devui1.rewardapp");
}
});
}
public void startNewActivity(Context context, String packageName) {
Intent intent = context.getPackageManager().getLaunchIntentForPackage(packageName);
if (intent == null) {
// Bring user to the market or let them choose an app?
intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse("market://details?id=" + packageName));
}
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
}

In order for getLaunchIntentForPackage() to work, that package needs to have an Activity that is suitable for being launched as an entry point into that app. The documentation includes this:
The current implementation looks first for a main activity in the category CATEGORY_INFO, and next for a main activity in the category CATEGORY_LAUNCHER. Returns null if neither are found.
This suggests you need one of the following on an Activity in your other package:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.INFO" />
</intent-filter>
Or
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
If that's not something you want, then you could try creating your own custom action string and using that to launch an activity exposing that specific action:
<intent-filter>
<action android:name="your.package.ACTION_NAME" />
</intent-filter>
public void startActivityWithPrivateAction(Context context, String packageName) {
Intent intent = new Intent("your.package.ACTION_NAME");
intent.setPackage(packageName);
List<ResolveInfo> activities = context.getPackageManager().queryIntentActivities(intent, 0);
if (activities.isEmpty() {
// no suitable activity was found; open the market instead.
intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse("market://details?id=" + packageName));
}
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
}

How to remove icon programatically (Android)

By remove the below intent-filter in AndroidManifest.xml, it can remove the icon after install.
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
But i have try the below when on Boot than remove the Icon, but the icon still remain after reboot. I have add the permission, and this reboot receiver is work.
public class BootBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
PackageManager p = context.getApplicationContext().getPackageManager();
ComponentName componentName = new ComponentName("com.example.removeicon","com.example.removeicon.LauncherActivity");
p.setComponentEnabledSetting(componentName,PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);
}
}
Or Put the Boot on service and AndroidManifest.xml intent-filter is not remove, the service is run and work.
package com.example.removeicon;
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
PackageManager p = getPackageManager();
ComponentName componentName = new ComponentName("com.example.removeicon","com.example.removeicon.LauncherActivity");
p.setComponentEnabledSetting(componentName,PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);
startService();
}

PackageManager p = getPackageManager();
ComponentName componentName = new ComponentName("com.example.removeicon","com.example.removeicon.LauncherActivity");
p.setComponentEnabledSetting(componentName,
PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);
Note that the icon may not be gone until the next reboot.

try this below code, this one worked for me
PackageManager p = ctx.getPackageManager();
p.setComponentEnabledSetting(((Activity)ctx).getComponentName(),
PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);

Start MAIN activity of the current application without knowing it's name

I am trying to write an utility method, that would be able to start activity (belonging to current application) marked as "android.intent.action.MAIN". The utility method should not accept any parameters.
Desired code:
public void startMainActivity(Context context) {
...
}
Manifest:
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
Any ideas?

This works since API Level 3 (Android 1.5):
private void startMainActivity(Context context) throws NameNotFoundException {
PackageManager pm = context.getPackageManager();
Intent intent = pm.getLaunchIntentForPackage(context.getPackageName());
context.startActivity(intent);
}

We used the nice solution of alex2k8 for a while until discovering it was not working on all devices on released version downloaded from Google Play.
Unfortunately the system didn't:
throw any exception
log the cause of the error
We used following workaround to solve it:
protected void startMainActivityWithWorkaround() throws NameNotFoundException, ActivityNotFoundException {
final String packageName = getPackageName();
final Intent launchIntent = getPackageManager().getLaunchIntentForPackage(packageName);
if (launchIntent == null) {
Log.e(LOG_TAG, "Launch intent is null");
} else {
final String mainActivity = launchIntent.getComponent().getClassName();
Log.d(LOG_TAG, String.format("Open activity with package name %s / class name %s", packageName, mainActivity));
final Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
intent.setComponent(new ComponentName(packageName, mainActivity));
// optional: intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
}

I think you'd have to find a list of all the activities declared in your manifest, and then use the intentFilter's actionsIterator() to iterate through all the actions of each activity's intent-filter, match the one that has intent.action.MAIN and then start that Activity.
The problem is I'm not sure how to retrieve a list of all your declared Activites from the manifest.