Develop Reference

Android app doesn't start at system boot

I've a reciever
public class MyBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Intent myStarterIntent = new Intent(context, MainActivity.class);
context.startActivity(myStarterIntent);
}
}
and have modified the AndroidManifest.xml, adding these lines
<receiver
android:enabled="true"
android:name=".MyBroadcastReceiver"
android:permission="android.permission.RECEIVE_BOOT_COMPLETED"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED"/>
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</receiver>
to section.
The application still does not start on system boot..any ideas appreciated. At least how can I monitor what is going on after device reboot (because I cant just use breakpoints in that case)

You need to provide Intent.FLAG_ACTIVITY_NEW_TASK flag when starting activity from BroadcastReceiver.
Intent myStarterIntent = new Intent(context, MainActivity.class);
myStarterIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(myStarterIntent);
This is how you can test the BroadcastReceiver.

Open Activity With Dial Code

I want to develop app that doesn't have icon launcher. The app will run alarmscheduler which triggered when app is installed or phone is rebooted.
The problem is how can I open the activity since the app doesn't have intent filter like below:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
Is there a way to handle dial code such as ##4635*#*# to open the activity ?
or any other solutions are welcomed.

You can do it with two ways:
1) as answer by #KishuDroid
2) By define code in manifest
public class MySecretCodeReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals("android.provider.Telephony.SECRET_CODE")) {
Intent i = new Intent(context, MainActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
}
}
}
In manifest file
<receiver android:name=".MySecretCodeReceiver">
<intent-filter>
<action android:name="android.provider.Telephony.SECRET_CODE" />
<data android:scheme="android_secret_code" android:host="4635" />
</intent-filter>
</receiver>
Note:
In Second method you must have to dial *#*#your_code#*#* and dont need to press call button
But in first method you can customise your prefix or postfix of code. For example *#your_code# or **your_code##. but you need to press call button.

You have to use Broadcast Receiver...
public class OutgoingCallReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
if(null == bundle)
return;
String phonenumber = intent.getStringExtra(Intent.EXTRA_PHONE_NUMBER);
Log.i("OutgoingCallReceiver",phonenumber);
Log.i("OutgoingCallReceiver",bundle.toString());
if(code.equals("#056700") {
intent.setComponent(new ComponentName("com.example", "com.example.yourActivity"));
And Your Android Manifest
<receiver android:name="com.varma.samples.detectcalls.receivers.OutgoingCallReceiver">
<intent-filter>
<action android:name="android.intent.action.NEW_OUTGOING_CALL"/>
</intent-filter>
</receiver>
Also, include the permission:
<uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS"/>

ActivityNotFoundException when trying to call an activity from another project

I'm trying to use another project I already have in my main project but when I call the activity from it, I get the ActivityNotFoundException: have you declared this activity in your androidManifest?. This is what i've done :
final Intent intent = new Intent();
ComponentName cName = new ComponentName("com.GCM.pushnotifications","com.GCM.pushnotifications.RegisterActivity");
intent.setComponent(cName);
startActivity(intent);
and in the manifest :
<activity android:name=".RegisterActivity" android:exported="true">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
What am i doing wrong? this is what I found on the net.

You just have to provide the activity class name as the second parameter of ComponentName
Change this
ComponentName cName = new ComponentName("com.GCM.pushnotifications","com.GCM.pushnotifications.RegisterActivity");
to
ComponentName cName = new ComponentName("com.GCM.pushnotifications","RegisterActivity");

Android - Boot Receiver Error

So I have a boot receiver that is supposed to call an intent service but the receiver isn't registering at all.
Manifest file -
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
<receiver android:name=".ClockReciever">
<intent-filter >
<action android:name="android.intent.action.BOOT_COMPLETED"/>
<action android:name="android.intent.action.QUICKBOOT_POWERON" />
</intent-filter>
</receiver>
ClockReceiver.java
public class ClockReceiver extends BroadcastReceiver {
private final String TAG = "ClockReciever";
#Override
public void onReceive(Context context, Intent intent) {
Log.d(TAG,"onRecive");
context.startService(new Intent(context, RefreshIntentService.class));
}
}
I think this is correct, but according to my logcat the ClockReciever is never called and the program crashes with a "Unable to instantiate receiver" error.
Any suggestions? Thank you

Here you have a typo
<receiver android:name=".ClockReciever">
Should be ClockReceiver, i.e. same as your class.
Cheers!

Android BroadcastReceiver can't receive any broadcast events

I have created a BroadcastReceiver to detect SDCard mount and unmount
event, however, I am not able to receive any events at all:
here's the AndroidManifest.xml:
<receiver android:enabled="true" android:label="SDCardMountReceiver" android:exported="true" android:name="xxx.broadcasts.SDCardBroadcastReceiver">
<intent-filter>
<action android:name="android.content.Intent.ACTION_MEDIA_MOUNTED"></action>
<!-- or <action android:name="android.content.Intent.ACTION_MEDIA_UNMOUNTED" />--></intent-filter>
</receiver>
And the SDCardMountReceiver class:
public class SDCardBroadcastReceiver extends BroadcastReceiver {
public SDCardBroadcastReceiver() {
super();
System.err.println("constructor");
}
public void onReceive(Context context, Intent intent) {
Log.d("SDCardBroadCastReceiver", "receive " + intent.getAction());
System.err.println("jonathan receive " + intent.getAction());
}
}

You also need to set the data scheme to "file".
<intent-filter>
<action android:name="android.intent.action.MEDIA_MOUNTED" />
<data android:scheme="file" />
</intent-filter>
Reference: android-developers thread

The Intent javadoc specifies a different action:name value.
Use "android.intent.action.MEDIA_MOUNTED" instead of "android.content.Intent.ACTION_MEDIA_MOUNTED"

If you register a broadcast receiver programmatically, you must also set the scheme to "file".
IntentFilter filter = new IntentFilter();
filter.addAction(Intent.ACTION_MEDIA_MOUNTED);
filter.addAction(Intent.ACTION_MEDIA_REMOVED);
filter.addDataScheme("file");
mContext.registerReceiver(mExternalStorageReceiver, filter);