I was able to get Astro to launch my activity when I selected a certain filetype. However, I don't know how to grab the intent when my activity starts!
public class Viewer extends ListActivity{
....
// Flag if receiver is registered
private boolean mReceiversRegistered = false;
// I think this is the broadcast you need for something like an incoming call
private String INCOMING_CALL_ACTION = "android.intent.action.VIEW";
// Define a handler and a broadcast receiver
private final Handler mHandler = new Handler();
private final BroadcastReceiver mIntentReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// Handle reciever
String mAction = intent.getAction();
Toast.makeText(context,"Found with passed context", Toast.LENGTH_LONG).show();
Toast.makeText(BallLidarViewer.this, "Found with my context", toast.LENGTH_LONG).show();
System.out.print("FOUND");
Log.d("FOUND","FOUND");
if(mAction.equals(INCOMING_CALL_ACTION)) {
// Do your thing
}
}
};
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
....
}
}
I can't get any of my test output code to be run when my activity starts. What am I doing wrong? Thank you!
If I get you right, you can simply call getIntent in your onCreate method.
To get the bundle of the intent, call getExtras on the intent.
Related
I want to update an Activity which is not the MainActivity.
So I start a second Activity via a onClick method in MainActivity.
Now the Activty "SecondActivity" is at front.
When I started a Thread in the "MainActivity" how can I reference to the "SecondActivity" to update their TextViews and so on?
PseudoCode
public class activity_MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ThreadSome threadSome= new ThreadSome();
threadSome.start()
}
onClick(View View){
Intent intent = new Intent(this, activity_Second.class);
startActivity(intent);
}
}
Inside Thread
public class ThreadSome extends Thread {
#Override
public void run() {
//This is what I don't know, so I just write what I want to do.
// I know the following Code is wrong and not working.
activity_Second.someTextView.setText("Hi");
}
}
Is a WeakReference the best way to do this, or better work with static TextView objects? How would you solve this problem?
Based on your description, I think you want to do something where there will be some ui change in activity stack based on some event performed in the forground activity. There is a good way to use onActivityResult() via startActivityForResult() but if this is not fullfilling your requirement directly then you can try something like below:
/**
UpdateActivity is the activity where some ui update or action will be taken based on event in EventActivity.
**/
public class UpdateActivity extends Activity {
private BroadcastReceiver mReceiver;
public static final String ACTION_UPDATE = "com.my.internal.activity.action";
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_update);
......
//Prepared Intent for broadcast receiver
IntentFilter intentFilter = new IntentFilter(ACTION_UPDATE);
//registering our receiver
this.registerReceiver(mReceiver, intentFilter);
.....
}
//This is the receiver section where you need to do the ui update
mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//extract our message from intent
String some_msg = intent.getStringExtra("msg_1"); //parameter received if passed in intent when broadcast called.
//log our message value
Log.i("Message", some_msg);
updateActivityUi();
}
};
private void updateActivityUi() {
// you need to write the code for the update which you want to do after an event done in other activity.
}
#Override
protected void onDestroy() {
super.onDestroy();
//unregister our receiver
this.unregisterReceiver(this.mReceiver);
}
}
public class EventActivity extends Activity {
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_event);
......
//Sending BroadcastReceiver against the action ACTION_UPDATE and it will be received by UpdateActivity.
if(condition_for_event) {
Intent i = new Intent(UpdateActivity.ACTION_UPDATE).putExtra("msg_1", "Hey! an event performed here.");
this.sendBroadcast(i);
}
.....
}
....
}
Let me know if it solved your issue.
I have a serious issue about passing data from BroadcastReceiver to an Activity. Let see my issue carefully. I have a class PhoneStateReceiver extends BroadcastReceiver that used to received an incoming phone.
public class PhoneStateReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
try {
System.out.println("Receiver start");
String state = intent.getStringExtra(TelephonyManager.EXTRA_STATE);
String incomingNumber = intent.getStringExtra(TelephonyManager.EXTRA_INCOMING_NUMBER);
if(state.equals(TelephonyManager.EXTRA_STATE_RINGING)){
}
}
catch (Exception e){
e.printStackTrace();
}
}
}
The incoming phone will be sent to an Activity, called ReceiverActivity. The ReceiverActivity receives the incoming phone and sends it to a server via a socket connection. The socket connection is initialized in the onCreate function. I googled and found server way to pass the data from BroadcastReceiver to an Activity. The common way is that send data via putExtra function and call startActivity. However, the way will call the onCreate again and then connect the socket, draw the UI again. Thus, it is not helpful in my case.
In my goal, If the phone receives an incoming call, it will send the incoming call to the ReceiverActivity. The ReceiverActivity receives the message and calls the send function. Which is the best way to do it? Thank you
The common way to pass data from a BroadcastReceiver to a ReceiverActivity that I used as follows
In PhoneStateReceiver class :
Intent intent_phonenum = new Intent(context, ReceiverActivity.class);
intent_phonenum.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent_phonenum.putExtra("phone_num", incomingNumber);
context.startActivity(intent_phonenum);
In ReceiverActivity class :
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
connect_socket();
Intent intent = getIntent();
phone_num = intent.getStringExtra("phone_num");
send(phone_num);
}
Simple without any third party libs.
Make sure BroadcastReceiver must be registered and also unregistered on OnPause().
You have to do two thing
Register a receiver in you activity like below.
public class MainActivity extends Activity {
Context context;
BroadcastReceiver updateUIReciver;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
context = this;
IntentFilter filter = new IntentFilter();
filter.addAction("service.to.activity.transfer");
updateUIReciver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//UI update here
if (intent != null)
Toast.makeText(context, intent.getStringExtra("number").toString(), Toast.LENGTH_LONG).show();
}
};
registerReceiver(updateUIReciver, filter);
}
}
Now in you service
public class PhoneStateReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
try {
System.out.println("Receiver start");
String state = intent.getStringExtra(TelephonyManager.EXTRA_STATE);
String incomingNumber = intent.getStringExtra(TelephonyManager.EXTRA_INCOMING_NUMBER);
if (state.equals(TelephonyManager.EXTRA_STATE_RINGING)) {
Intent local = new Intent();
local.setAction("service.to.activity.transfer");
local.putExtra("number", incomingNumber);
context.sendBroadcast(local);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
There is a very simple design pattern you can use here to ease communication between your classes and also decouple your code: publisher/subscriber. My favorite library for this is EventBus:
First, add to your build.gradle file:
compile 'org.greenrobot:eventbus:3.0.0'
Then, create a simple POJO - Plain Old Java Object like this:
public class OnReceiverEvent{
private String phoneNumber;
public OnReceiverEvent(String phone){
this.phoneNumber = phone;
}
public String getPhoneNumber(){
return phoneNumber;
}
}
Next, by making your Receiver class a publisher, and your Activity a subscriber, you should be able to easily pass the information to your activity like this:
//inside your PhoneStateReceiver class when you want to pass info
EventBus.getDefault().post(new OnReceiverEvent(phoneNumber));
Next, inside your activity, simply do this:
//onStart
#Override
public void onStart(){
super.onStart();
EventBus.getDefault().register(this);
}
//onStop
#Override
public void onStop(){
super.onStop();
EventBus.getDefault().unregister(this);
}
Finally, handle the posted data i.e phoneNumber value:
#Subscribe
public void onPhoneNumberReceived(OnReceiverEvent event){
//get the phone number value here and do something with it
String phoneNumber = event.getPhoneNumber();
//display or something?
}
UPDATE
If you have another Event that you want this activity to subscribe to, simply create a method like you did in the first one using the #Subscribe annotation.
#Subscribe
public void onSomeOtherEvent(EventClassName event){
//get the variables here as usual;
}
This is the easiest way to pass the data from your receiver to your activity without having to worry about starting the activity over and over!
I hope this helps and good luck!
So I understand you don't want to recreate your Activity everytime.
In your Intent changing this flag will help you :
intent_phonenum.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
In Intent class if you read method summary of FLAG_ACTIVITY_CLEAR_TOP:
If set, and the activity being launched is already running in the
current task, then instead of launching a new instance of that activity,
all of the other activities on top of it will be closed and this Intent
will be delivered to the (now on top) old activity as a new Intent. (you can read more ...)
In this case: If your app is running and you have an Activity instance then Intent will not recreate your Activity. But assume that your app is in closed state and when BroadcastReceiver triggered, the Intent will create new Activity because you don't have instance of that Activity.
#Edit :
You can specify special Intent like that in your BroadcastReceiver:
public void onReceive(Context context, Intent intent) {
Bundle extras = intent.getExtras();
Intent i = new Intent("mycustombroadcast");
i.putExtra("phone_num", incomingNumber);
context.sendBroadcast(i);
}
Then in your Activity inside onCreate() register receiver like that :
BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
Bundle bundle = intent.getExtras();
int incoming_number= bundle.getInt("phone_num");
Log.e("incoming number", "" + incoming_number);
}
};
//then register receiver like that :
registerReceiver(broadcastReceiver, new IntentFilter("mycustombroadcast"));
You can unregister Receiver in onDestroy() : unregisterReceiver(broadcastReceiver);
Also another way is overriding onNewIntent() in your Activity:
#Override
protected void onNewIntent(Intent intent) {
//your intent is here, you can do sth.
super.onNewIntent(intent);
}
I've set up a BroadcastReceiver as a way for one activity to stop another. The activity I want to stop looks something like this:
public class TestActivity extends Activity {
private static final String TAG = "TestActivity";
private Context mContext = null;
private final BroadcastReceiver mQuitReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals("finish_activity")) {
mLogUtil.d(TAG, "onReceive() finishing...");
finish();
}
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mContext = this;
mLogUtil.d(TAG, "onCreate()");
LocalBroadcastManager.getInstance(mContext).registerReceiver(mQuitReceiver, new IntentFilter("finish_activity"));
// Other initialization stuff...
}
#Override
protected void onDestroy()
{
LocalBroadcastManager.getInstance(mContext).unregisterReceiver(mQuitReceiver);
// Other de-initialization stuff...
super.onDestroy();
}
}
And I finish it from another activity via:
Intent intent = new Intent("finish_activity");
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
My question is, do I actually need to un-register that receiver manually if the receiver is tied to the activity instance anyway? Or does the finish() method clean that up for me?
You have to unregister the receiver, since it isn't really tied to the activity. As you can see in the source, finish doesn't know about receivers you've registered, so there's nothing it can really do to automate this.
To expand on this, as you can see in the LocalBroadcastManager source the application context you pass to getInstance() isn't actually used for anything, it's the application context that's used. So the LocalBroadcastManager doesn't have any sort of reference to your Activity to know it's lifecycle.
I have a service that listens for (ON_BATTERY_CHANGE), then onReceive service sends a Broadcast to My MainActivity. The problem is that I somehow can't get them from service to my main activity. Code: Main Activity:
public class MainActivity extends Activity
private BroadcastReceiver batteryReceiverService;
private TextView text2;
....
protected void onCreate(Bundle savedInstanceState) {
text2=(TextView)findViewById(R.id.TV_text2);
batteryReceiverService = new BroadcastReceiver(){
#Override
public void onReceive(Context context, Intent intent) {
text2.setText("left: "+intent.getStringExtra("H")+" hours "+intent.getStringExtra("M")+" minute(s)");
Log.e("text2","text2 HHH " +intent.getStringExtra("H")); //log shows 0
Log.e("text2","text2 MMM " +intent.getStringExtra("H")); // log shows 0
}
};
registerReceiver(batteryReceiverService, new IntentFilter(UltimateBatterySaverService.BROADCAST_ACTION));
....
#Override
protected void onDestroy() {
unregisterReceiver(batteryReceiverService);
super.onDestroy();
}
Service:
public class UltimateBatterySaverService extends Service {
private Intent intent;
static final String BROADCAST_ACTION = "lt.whitegroup.ultimatebatterysaver";
private BroadcastReceiver batteryLevelReceiver;
....
public void onCreate() {
super.onCreate();
intent = new Intent(BROADCAST_ACTION);
}
#Override
public void onDestroy() {
unregisterReceiver(batteryLevelReceiver);
super.onDestroy();
}
IntentFilter batteryLevelFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
batteryLevelReceiver = new BroadcastReceiver(){
#Override
public void onReceive(Context context, Intent intent){
// Receiving data, calculating and etc
averageChargingH=timeAllInHours;
averageChargingM=timeAllInMinutes;
// to put extras and send broadcast
does();
......
public void does(){
String strLong = Long.toString(averageChargingH);
String strLong2 = Long.toString(averageChargingM);
Log.e("cccccc","strLong h "+strLong); // getting good value not 0(everything ok)
Log.e("cccccc","strLong2 m"+strLong2); // getting good value not 0(everything ok)
intent.putExtra("H", strLong);
intent.putExtra("M", strLong2);
sendBroadcast(intent);
}
Any ideas why my information is not transfered correctly?
The does() method seems to be using variables in the same scope as onReceive so I'm guessing that the intent variable in does() is actually the Intent passed in from onReceive.
Try adding some logging before sending the broadcast to check if the action of the intent is correct, or simply create the broadcast intent in the onReceive method and name it intent2.
I my app I'm calling a Broadcast Receiver to read incoming Text Messages and say it aloud. My Broadcast Receiver gets called properly, it reads the text message properly but when it comes to the speak() method, it just crashes. Here's my code:
This is the BroadcastReceiver:
public class DrivingModeSpeaker extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent)
{
// TODO Auto-generated method stub
int n;
Bundle bundle=intent.getExtras();
Object messages[]=(Object[])bundle.get("pdus");
SmsMessage smsMessage[]=new SmsMessage[messages.length];
for(n=0;n<messages.length;n++)
{
smsMessage[n]=SmsMessage.createFromPdu((byte[])messages[n]);
}
//show first message
String sms1=smsMessage[0].getMessageBody();
String from=smsMessage[0].getOriginatingAddress();
Toast toast=Toast.makeText(context,"In DrivingModeSpeaker BR",1);
toast.show();
DrivingMode.speakSMS(sms1);
}
}
And this is DrivingMode.java which contains the speak() method:
public class DrivingMode extends Activity {
private static TextToSpeech myTts;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.message_m);
myTts = new TextToSpeech(this,ttsInitListener);
}
private TextToSpeech.OnInitListener ttsInitListener=new TextToSpeech.OnInitListener() {
#Override
public void onInit(int version) {
// myTts.speak(""+o, 0 ,null);
}
};
public static void speakSMS(String sms)
{
myTts.speak(sms,0,null);
}
}
I have tried out this code in a separate project, it works. But in my main project, it doesn't - could it be because of two broadcast receivers clashing or something? I dunno, I'm new to Android, please help!
Currently you are trying to call Activity method by Creating an instance of Activity which through NullPointerException if Activity is not running. so instead of calling Activity's method start Activity from BroadcastReceiver and send sms data using Intent.putExtra as :
For Example :
public void onReceive(Context context, Intent intent)
{
// Your code here....
Toast toast=Toast.makeText(context,"In DrivingModeSpeaker BR",1);
toast.show();
// start Activity here
Intent intent = new Intent(context,
DrivingMode.class);
intent.putExtra("sms", sms); //<<< put sms text
context.startActivity(intent);
}
and in DrivingMode onCreate method get sms data and call speakSMS method as :
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.message_m);
Bundle extras = getIntent().getExtras();
myTts = new TextToSpeech(this,ttsInitListener);
DrivingMode.speakSMS(extras.getString("sms"));
}
also use TextToSpeech.setOnUtteranceCompletedListener for finishing Activity at the end of Speak