I would like to go back to the Main Activity at a certain point in my application. I tried calling the Activity in an Intent as usual, however since the Activity name for the main class is called "android.intent.action.MAIN", which is the general name of every application's main activity, a "Complete Action Using:" menu pops up with every possible application on the phone as an option. I do not want this; what I want is that the main activity for my application loads up.
How can I achieve this?
Thank you in advance!
You can also specify a specific Activity to launch like so:
Intent nextActivityIntent = new Intent(this, MyActivity.class);
startActivity(nextActivityIntent);
As per the Intent documentation, the ACTION_MAIN flag is used to specify that you want to launch an application using the application's main entry point. You generally do not use it in your app unless you are trying to open another app.
Related
For an App I am developing, I override the back button to make it act like the home button so that the state of the main activity is preserved even when the app is exited. Now, I also send a notification to the user from time to time using a service. When this notification is pressed I want to open the main activity again. I noticed though that this creates a second instance of the app, which creates major problems. I am trying to make the main activity go to the front again, without calling oncreate again like so:
Intent to launch main activity again:
Intent notificationIntent = new Intent(this, MainActivity.class);
notificationIntent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
This doesn't work though. I still end up with two instances of my main activity. Does anybody know how to fix this?
By the way, I already have android:launchMode="singleInstance" in my manifest.
There's a way to force the OS to create only one instance of an activity and thats using the tag launchMode in the Manifest as shown below:
<activity android:name="YourActivity"
android:launchMode="singleInstance"/>
Hope this Helps...
Regards
Try adding this flag to the intent .addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP), works for me.
How do I get my app to appear in on the screen after it has been replaced by some other screen/activity? Some network event occurs and my application wants to reappear in the foreground (presumably in a polite manner).
I think I need to do something like:
contxt.startActivity(myActivity);
I don't want to create another instance of my app or cause it to restart, but I want it to appear.
Use FLAG_ACTIVITY_NEW_TASK
Intent intent = new Intent(contxt, myActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
contxt.startActivity(intent);
In your myActivity onNewIntent is called. I assume myActivity is the top activity in your app current stack
If Activity manager launches the MainActivity through intent-filter with action=main, and category=launcher, then which type of intent is used?
I'm confused little bit. Is it implicit intent?
An intent is an abstract description of an operation to be performed. Its most significant use is in the launching of activities.
when the user clicks on the application icon, the android system looks in the manifest file for the intent with
action="android.intent.action.MAIN"
and
category="android.intent.category.LAUNCHER".
MAIN action is the main entry point of the application.
LAUNCHER category means it should appear in the Launcher as a top-level application.
Intent is just a piece of information about intention. Intent do not starts anything. It just inform OS that there is a need to do something (i.e start app). System looks for apps able to resolve this intention, starts them and pases to them starting intent (becouse you can pass some portion of data in it).
When user clicks app icon in launcher, launcher application generates and sens intent to OS (with explicit name of desired application to start). Android creates separate DVM, main activity class, starts acrivity's life cycle with calling onCreate() and brings activity to foreground.
When the user selects your app icon from the Home screen, the system calls the onCreate() method for the Activity in your app that you've declared to be the "launcher" (or "main") activity. This is the activity that serves as the main entry point to your app's user interface.
You can define which activity to use as the main activity in the Android manifest file, AndroidManifest.xml, which is at the root of your project directory.
The main activity for your app must be declared in the manifest with an intent-filter that includes the MAIN action and LAUNCHER category(That you know probably).
If a component does not have any intent filters, it can receive only explicit intents. A component with filters can receive both explicit and implicit intents.
Therefore, activities that are willing to receive implicit intents must include "android.intent.category.DEFAULT" in their intent filters. Filters with "android.intent.action.MAIN" and "android.intent.category.LAUNCHER" settings are the exception. They mark activities that begin new tasks and that are represented on the launcher screen. They can include "android.intent.category.DEFAULT" in the list of categories, but don't need to.
For more details please refer this link:
http://developer.android.com/guide/components/intents-filters.html
My boss asked me to prove that my application behaves properly when summoned by another application (dunno why he asked that).
So I have two apps here, one launches a second one. How I launch the specific app I want? Using Intent launch seemly any generic app that reaches a certain goal, not the app I really want.
Give this a try.
Intent secondIntent = new Intent();
secondIntent.setAction(Intent.ACTION_MAIN);
secondIntent.setClassName("com.example", "com.example.YourSecondApp");
startActivity(secondIntent);
I should point out that com.example should be the package of your second application (the one you want to call) and com.example.YourSecondapp is the class name where you have your onCreate() method.
Intent secondApp = new Intent("com.test.SecondApp");
startActivity(secondApp);
Check out for more examples
http://developer.android.com/resources/faq/commontasks.html#opennewscreen
Create one Intent using the following code
Explicit Intent
When you know the particular component(activity/service) to be loaded
Intent intent = new Intent();
intent.setClass("className/package name");
start<Activity/Service>(intent);
Imlicit Intent
When we do not have the idea which class to load and we know the Action to be perform by the launched application we can go with this intent.
Action needs to set, and the Android run time fallows the intent Resolution technique and list out(one or more components) the components to perform the action. from the list out components (if more than one), user will get the chance to launch his chosen application
HI,
I have 2 projects (each has its own apk).
Can you please tell me how can I launch an activity which is in another apk that I created?
I have this activity which I want to launch from another project:
// what should I put in here so that I can launch this from another activity in another project?
You would have to implement an Intent interface. I.e. have your activities respond to specific Intents specified via Intent-filters in your manifest. Have a look at this page:
http://android-developers.blogspot.com/2009/11/integrating-application-with-intents.html
Intent myIntent = new Intent();
myIntent.setClassName("com.activity1", "com.activity2");
startActivity(myIntent);
Activity 1 is the activity that is already running.
Activity 2 is the com name of the activity you want to launch.