I am sending custom broadcasts from AppWidgetProvider class:
intent = new Intent();
intent.setAction("packagename.intent.action.SET_VOLUME_STATE");
context.sendBroadcast(intent);
and listening for them in BroadcastReceiver class:
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals("packagename.intent.action.SET_VOLUME_STATE"))
{
//do stuff
}
}
and have also registered the receiver with intent filter in manifest file. The problem is I am receiving the broadcast intent very late ~20-30 seconds after it is broadcast and sometimes it is sooner than that. I expect to receive the broadcast immediately and not lag behind. Am i missing something?
Related
the title says all, I need to change the variable of my service from a activity in my other app , what to finalize the service or not, this is possible?
I found the Message object , but I do not quite understand
The simplest solution would be to implement a BroadcastReceiver. Your Service listens for the Broadcast and the other App sends the Broadcast.
Example Reciever:
public class MyReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// Get bundle from intent and use it to set your Variable in your Service
}
}
Example Broadcaster (courtesy of Vogella):
Intent intent = new Intent();
intent.setAction("de.vogella.android.mybroadcast");
sendBroadcast(intent);
I have an application that using "AlarmService". For handling alarms i have a Broadcast receiver. That receiver has to start certain activity. Code i'm using for achieving that is following:
#Override
public void onReceive(Context context, Intent intent) {
...other code....
Intent intIntent = new Intent(context, MainActivity.class);
intIntent .putExtra("IsAlarm", true);
Intent alarmChooser = Intent.createChooser(intIntent , "Alarm");
alarmChooser.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(alarmChooser);
}
That works but only if activity isn't shown already (if it's not in the foreground). If called activity is already opened nothing happens. How can i overcome that?
Is there a flag that will start the activity if it's not started OR send intent to it even if it's in the foreground?
P.S. i tried using dedicated "broadcast" above the provided code. Reciever for that broadcast is registered programmatically in the MainActivity: "onResume" would register dedicated receiver, "onPause" would unregister it. That way in case MainActivity is already on it will receive a broadcast but then i have a problem when phone goes to "stand by" - "dedicated" receiver is unregistered.
Check in the activity onNewIntent callback
there should be the new intent from the receiver
I think you don't need the chooser:
#Override
public void onReceive(Context context, Intent intent) {
Intent intIntent = new Intent(context, MainActivity.class);
intIntent.putExtra("IsAlarm", true);
context.startActivity(intIntent);
}
i develop an Android-Bluetooth App with 3-4 Activitys. Now i have to receive bluetooth data in any of these activitys.
I think i have to implement a Service which contains a BroadcastReceiver which listens to incoming BlueTooth Data and send a Broadcast, but i don't know how to do that.
Thanks in advance.
You can implement your own BroadcastReceiver. So, when your LocalService receive a data, it will notify using sendBroadcast method. Your activities should register the specific BrodcastReceiver.
In your Service
Notify about received messages:
public void onMessageReceived(String message) {
Intent intent = new Intent(ACTION_BLUETOOTH_MESSAGE);
intent.putExtra(BLUETOOTH_MESSAGE_CONTENT, message);
sendBroadcast(intent);
}
On each activity
Registering the broadcast receiver:
registerReceiver(messageReceiver,
new IntentFilter(ACTION_BLUETOOTH_MESSAGE));
Implementation of the broadcast receiver:
private BroadcastReceiver messageReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String message = intent.getStringExtra(BLUETOOTH_MESSAGE_CONTENT);
//Do something you want
}
};
From the examples this looked straightforward. Maybe you can show me what I did wrong. I can't get an activity to receive a broadcast sent from a local service.
I have Activity1 that start Service1:
startService(new Intent(Activity1.this, Service1.class));
Activity1 then starts Activity2:
startActivity(new Intent(Activity1.this, Activity2.class));
Service1, a local service, listens for downloads:
protected final BroadcastReceiver service2DownloadBroadcastReceiver = new BroadcastReceiver()
{
public void onReceive(final Context context, final Intent intent)
{
...
broadcastDownloadFinished(Uri.fromFile(downloadedFile));
The broadcast receiver of Service1 then broadcasts its own message:
protected Intent broadcastDownloadFinished(final Uri uri)
{
final Intent intent = new Intent(ACTION_DOWNLOAD_FINISHED).setData(checkNotNull(uri));
sendBroadcast(intent);
Activity2, which is in the foreground at the time, listens for the ACTION_DOWNLOAD_FINISHED intent using its own broadcast receiver:
private final BroadcastReceiver activity2DownloadBroadcastReceiver = new BroadcastReceiver()
{
public void onReceive(final Context context, final Intent intent)
{
Log.i(Activity2.class.getSimpleName(), "Received download event: " + intent.getAction() + " " + intent.getData());
Activity2 of course registers the receiver:
protected void onResume()
{
super.onResume();
final IntentFilter downloadIntentFilter = new IntentFilter();
downloadIntentFilter.addAction(ACTION_DOWNLOAD_FINISHED);
registerReceiver(activity2DownloadBroadcastReceiver, downloadIntentFilter);
In case it matters, ACTION_DOWNLOAD_FINISHED is something like "com.example.intent.action.DOWNLOAD_FINISHED".
Service1 receives the download manager event in its receiver and apparently broadcasts its own custom event, but Activity2 never seems to receive it. What did I do wrong? Is it a problem to broadcast an intent in the middle of processing another one? (I wouldn't think so---this is asynchronous, right?)
Update: Just to make sure there is no problem sending a broadcast in the middle of receiving a broadcast, I changed my broadcast code to actually perform the broadcast three seconds later on the main thread:
Log.i(getClass().getSimpleName(), "...ready to broadcast");
final Intent intent = new Intent(ACTION_DOWNLOAD_FINISHED).setData(checkNotNull(uri));
mainThreadHandler.postDelayed(new Runnable()
{
public void run()
{
Log.i(getClass().getSimpleName(), "...broadcasting");
sendBroadcast(intent);
Log.i(getClass().getSimpleName(), "...broadcasted");
}
}, 3000);
Log.i(getClass().getSimpleName(), "...scheduled to broadcast");
As expected, the log says:
...ready to broadcast
...scheduled to broadcast
...broadcasting
...broadcasted
Yet nothing is received in the activity. Please help.
Eureka! I found it! The problem is that I supplied a data URI in my broadcast intent. The Android intent matching rules get a little complicated. If you supply a data URI, then your intent filter must specify a matching MIME type.
Unfortunately, although the Android documentation says that the data type can be inferred from the data URI, apparently Android doesn't know that a file://.../example.jpg is an image. So this doesn't work:
intentFilter.addDataType("image/*");
However, instead of specifying a type, I can specify a scheme that I accept:
intentFilter.addDataScheme("file");
That works! It's a little rough---and a little artificial to restrict my broadcasts to file: URIs, but as that's all I'm using for the moment, it works.
Note that apparently I could manually specify the MIME type in the intent when I broadcast it, but that's too much trouble for now, as I'm downloading images from Picasa so I already know that they are images (and don't care the specific MIME type). And if it gets too much trouble, I could ditch the whole setData() thing altogether and set an extra---but of course I want to do things the Right Way.
have you included your receiver in your activity's manifest?
<receiver
android:name=".YourReceiver">
<intent-filter>
<action
android:name="intent_name"></action>
</intent-filter>
</receiver>
App A has this BroadcastReceiver in its manifest (within <application>):
And this receiver:
public class RemoteControl extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Log.w(TAG, "Look what I did!");
}
}
I'm trying to trigger this from App B:
public void onClick(View v) {
Log.w(TAG, "Sending stuff");
Intent i = new Intent("app.a.remotecontrol");
i.setData("http://test/url");
sendBroadcast(i);
}
For whatever reason, the onReceive() in App A is never triggered even though it's broadcasted from App B. What can be the cause of this?
EDIT & SOLUTION: I forgot to write that I used setData() on the Intent before broadcasting it. That was indeed the problem: as soon as I removed setData(), the broadcast worked as intended.
Originally I forgot to write that I used setData() on the Intent before broadcasting it. That was indeed the problem: as soon as I removed setData(), the broadcast worked as intended.
I've switched to use putExtra() instead for the Intent metadata:
Intent i = new Intent("app.a.remotecontrol");
i.putExtra("url", "http://test/url");
sendBroadcast(i);