I am creating a new intent like this:
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
And I want to override its onCreate or onPause methods. How can I do it?
thanks.
An Intent is compared to Intent filters as they're definded in the Apps Manifest's. If an Intent filter matches, the corresponding Activity or Service is started.
So an Intent itself has no onCreate or onPause method.
The best you can do is, to create an Activity with the required behavior, put a SurfaceView with Camera logic in it and start it with your own intent.
Here is the link to Androids guide to camera apps. It's not too difficult to write the necessary Activity.
If you start a new intent you ask the system to call any activty that is registered for this action/namespaces. If you yourself register this in your app you can of course change the onCreate() or onPause(), but usually you have no possibility to change how the intent is handled by the other app. Furthermore I do not get your use-case, if you maybe make clear what you want to do SO could be more of assitence.
Related
I'm trying to recreate() and activity on Android. I need additional data to be passed via an Intent to the recreated activity. How can this be done?
The following code does not work.
getIntent().putExtra("flag",true);
recreate();
You can call recreate() and save your date into SharedPreferences. In this way you are free to do many things and also the previous activity is completely destroyed before NewActivity begin. Take a look at this deep StackOverflow answer.
Why don't you restart activity via Intent :
Intent intent = getIntent();
intent.putExtra("your","params");
finish();
startActivity(intent);
Form Activity Login I call
Intent intent=new Intent(LogIn.this,BRInfoActivity.class);
From Activity BrActivityList I Call
Intent intent=new Intent(BRActiviList.this, BRInfoActivity.class);
intent.putExtra("BRinfo", objBR);
And Now in BRInfoActivityList
Intent i = getIntent();
BrInfoEN objBR=(BrInfoEN)i.getSerializableExtra("BRinfo");
Now i want if(intent==BrActivityList)The last two above line execute otherwise does not.How to do it?
If you will start activity with
startActivityForResult().
Then you can use getCallingActivity() to get caller.
Form Activity Login call this--
Intent intent=new Intent(LogIn.this,BRInfoActivity.class);
intent.putExtra("call_from","ActivityClass");
From Activity BrActivityList Call--
Intent intent=new Intent(BRActiviList.this, BRInfoActivity.class);
intent.putExtra("call_from", "BRActivity");
Now, when you get the intent, compare the "call_from" string in an if-else block! That's it!
May this help you...
The new intent comes as part of onNewIntent(Intent). The original Intent is still available via getIntent().
You put whatever code you need to into onNewIntent in order to update the UI with the new parameters; probably similar to what you're doing in onCreate.
Also, you probably want to call setIntent(intent) in onNewIntent to make sure future calls to getIntent() within the Activity lifecycle get the most recent Intent data.
Inside a broadcast receiver I want to start my app (Activity) and pass in some data.
My problem is that the extras don't seem to carry over into the activity. I am trying to get the data inside the onNewIntent(Intent i) function.
Any ideas?
Here is my current attempt in the BroadcastReceiver:
Intent intSlider = new Intent();
intSlider.setClass(UAirship.shared().getApplicationContext(), SliderMenuActivity.class);
intSlider.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intSlider.putExtra("action", ScreensEnum.Object);
intSlider.putExtra("objectId", objectId);
intSlider.putExtra("objectCode", objectCode);
intSlider.putExtra("userId", userId);
UAirship.shared().getApplicationContext().startActivity(intSlider);
EDIT - Added code used in onNewIntent() and onCreate()
The following code works great in onCreate() when the app isn't currently running. For when the app is already running the same code doesn't work (i.e. no extras) from the onNewIntent() function.
Intent intent = getIntent();
if(intent.hasExtra("objectId")) {
loadDetail(intent.getStringExtra("objectId"), "2w232");
}
The problem is getIntent() method. It always returns the intent that started the activity, not the most recent one. You should use intent that was passed to onNewIntent method as an argument.
We stumbled upon this problem once, when we were trying to launch/call onNewIntent on an Activity in response to a local notification tap. The extras that we put on our Intent were disappearing at the time onNewIntent received it.
I don't remember this being documented anywhere back then, but the "problem" was that we weren't setting the action field on the Intents that we prepared. Turns out if the Intent received by your Activity doesn't have an action set using setAction, the system still delivers the Intent to its destination, but doesn't transmit the extras you have set while creating the Intent.
TL;DR:
If you encounter this problem with an Intent with no action, calling setAction to set an arbitrary action value before sending the Intent might fix it.
Extract from the docs
This is called for activities that set launchMode to "singleTop" in
their package, or if a client used the FLAG_ACTIVITY_SINGLE_TOP flag
when calling startActivity(Intent). In either case, when the activity
is re-launched while at the top of the activity stack instead of a new
instance of the activity being started, onNewIntent() will be called
on the existing instance with the Intent that was used to re-launch
it.
An activity will always be paused before receiving a new intent, so
you can count on onResume() being called after this method.
Note that getIntent() still returns the original Intent. You can use
setIntent(Intent) to update it to this new Intent.
I think the last paragraph explains your problem.
You have to set the flag FLAG_ACTIVITY_SINGLE_TOP or set launchMode singleTop in the manifest file.
Of course when onNewIntent is called you do not use getIntent but the Intent received as argument.
onNewIntent will be called when the activity instance already exists. For example, if last time you pressed the Home Screen button.
I wrote a solution that worked for me here: Intent with old extra in onCreate() for singleTask Activity
You can store the last received intent in a member variable (mLastIntent).
Then you can use this member in your onResume() method to query for your extra data.
private Intent mLastIntent;
#Override
protected void onNewIntent(Intent intent) {
mLastIntent = intent;
};
Hi friends
can anybody tell what is the use of intent filter and what is difference between intent and intent filter
Thanks
An Intent is an object passed to Context.startActivity(),Context.startService() or Activity.startActivityForResult() etc. to launch an activity or get an existing activity to do something new.
While an Intent filter describes a capability of the component(like activities, services, and broadcast receivers )
For more details see this
Intent's are used to start new activity from the current activity. With two ways
1) Activity.startActivity(intent);
2) Activity.startActivityForResult(intent,rqwuestCode);
//The above thing's you need to put in .java file
Intent-filter you need to mention on manifeast file.
// Intent filter are used for broadcast receiver. Whenever the intent filter condition is match the android OS will launch that activity.
An intent is an object that can hold the os or other app activity and its data in uri form.It is started using startActivity(intent-obj)..\n whereas IntentFilter can fetch activity information on os or other app activities.
I am intercepting sms messages with some information in them. Then in my SmsListener I'm creating notification to show in statusbar.
Then, when user clicks on a notification I want
Bring MainActivity to foreground (If such activity does not exist yet it should be created)
Pass to it data from the sms
Perform some ui changes basing on this data in this MainActivity
My activity is defined as
<activity
android:name=".MainActivity"
android:screenOrientation="sensor"
android:label="#string/app_name"
android:launchMode="singleTask"/>
Activity is launched as
Intent i = new Intent();
i.setClass(context, MainActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
Also in my activity I have overridden method onNewActivity
#Override
public void onNewIntent(Intent intent){
super.onNewIntent(intent);
// I have data from broadcast in intent variable passed to this activity
processDataFromBroadcast(intent);
}
It works fine if the MainActivity already exists but if MainActivity does not exist it is started however onNewIntent was not called
Then I tried to invoke processDataFromBroadcast from onCreate: processDataFromBroadcast(getIntent()).
First time data is passed correctly from my broadcast to the activity.
However if MainActivity is sent to background and then again brought to foreground either onCreate or onNewIntent is called and processDataFromBroadcast is executed again with intent sent by broadcast and thus my MainActivity is updated with data from broadcast every-time the app is bringing to foreground - the latter is unwanted, how can I make my activity to forget this intent after first handling.
Here is sample application.
For an activity to launch only one instance of itself, have a look at the <activity> manifest element, and particularly android:launchMode. You want to configure it with either singleTask or singleInstance.
To pass data to your activity, you add data to the Intent you use to open it. To pass data with the intent, use the putExtra() methods of the intent before sending it off, and getExtra() methods to retrieve them in your receiving activity.
I'm assuming that you know roughly how intents work, but if not you could learn more about intents by taking a look at this Android developers article.
in case your problem is still unresolved, as I was just running into the same issue, here's how I solved it:
I am putting a timestamp as intentId as an extra upon the intent during it's creation. the first time, I am handling the intent in onCreate() or onNewIntent() I am reading the intentId and store it as the last intent handled. so the next time onCreate() or onNewIntet() is invoked I can check the intentId and if it equals the id of the last intent handled, I ignore it! It don't know if this helps in your case, maybe you can adopt it.
To keep intentId independent from activity lifecycles you could persist it in the userdefaults.
I agree that one would expect calling setIntent(new Intent()) in onNewIntent should do the trick.
It it late to answer, but it might be helpful to others looking for the solution.
Just add below lines of code :
Intent mIntent = new Intent(this, SplashActivity.class);
mIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); // You need this if starting the activity from a service
mIntent.setAction(Intent.ACTION_MAIN);
mIntent.addCategory(Intent.CATEGORY_LAUNCHER);
Where SplashActivity is the name of initial application that is the first screen of your application.
Hope it helps. :)