I have two applications each with one activity in them, the first does this when you press a button:
final private static String START_APP_INTENT = "com.example.app1.START_APP2";
Intent intent = new Intent(START_APP_INTENT);
startActivity(intent);
The second application has the following in its android manifest file:
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.app2.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<action android:name="com.example.app1.START_APP2" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
When I press the button I get the following exception:
Caused by: android.content.ActivityNatFoundException: No Activity found to handle Intent { act=com.example.app1.START_APP2 }
My app2 has that intent filter. Why am I getting this exception?
Your <intent-filter> isn't correct. You have this:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<action android:name="com.example.app1.START_APP2" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
You need this:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="com.example.app1.START_APP2" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
The first filter is so that your app will show up in the list of available applications. The second filter is for use by the other application. When an application calls startActivity() and there is no explicit component specified in the Intent, Android automatically adds the DEFAULT category to the Intent. Since you haven't got the DEFAULT category in your <intent-filter>, it does not match and Android cannot find a suitable activity to start.
Related
I would like to have two main activities in my app. So in my manifest I put:
<activity
android:name="mypackage1.MainActivity"
android:label="#string/title_activity_main">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="mypackage2.MainActivity2"
android:label="#string/title_activity_main2">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
Two icons are created in my apps menu. But when I click on each of them the first activity MainActivity is always launched. Is it possible to have two main activities? If so, what's wrong with what I did?
Thanks
The LAUNCHER intent filter is what determines what shows up in the app drawer/launcher. That is why you get two icons shown up.
However, you also set the DEFAULT intent filter, which sets the default Activity for the whole package. Since you set it twice, you get the problem of precedence of the first/latest registered. When you remove the DEFAULT filter, you will be able to start whatever you click on in the launcher.
In short, remove the following line from both Activities:
<category android:name="android.intent.category.DEFAULT" />
Yes, just mark two or more of your <activity>s as LAUNCHER within your manifest.
In addition you have to set the android:taskAffinity attribute on both of your Launcher-Activities which specify the exact package and Activity to be started.
<activity android:label="MyApp" android:name=".MyApp" android:taskAffinity="com.example.MainActivity">
<intent-filter>
<action android:name=".MyApp"/>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:label="Settings" android:name=".Settings" android:taskAffinity="com.example.SettingsActivity" >
<intent-filter>
<action android:name=".Settings"/>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
Use android:documentLaunchMode="intoExisting", to launch a separate task based on the intent's Component name and data URI. Without this (by default), the activity will share all the same activities, as android:documentLaunchMode default to none.
intoExisting: The system searches for a task whose base intent's ComponentName and data URI match those of the launching intent. If the system finds such a task, the system clears the task, and restarts with the root activity receiving a call to onNewIntent(android.content.Intent). If the system does not find such a task, the system creates a new task. source
<activity
android:name=".CameraActivity"
android:exported="true"
android:documentLaunchMode="intoExisting"
android:label="#string/app_1_label">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ProfilePoseNetActivity"
android:exported="true"
android:documentLaunchMode="intoExisting"
android:label="#string/app_2_label">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
The intention of potroae using task affinities to prevent your 2 activities from sharing the same task. However, it is annoying to have to select a task name, i.e. com.example/SettingsActivity for every task you want to launch separately.
I am trying to use Implicit intent to launch an activity within the same application and for an activity of another application(my other application, not the native one), but couldn't succeed in any of the cases.
Here is my sample code for the first part (i.e. to launch an activity within the same application):
Inside Activity TESTActivity
Intent intent = new Intent();
intent.setAction("com.myapp.game.myimplicit_action");
startActivity(intent);
and here is my manifest file declaration for some activity say 'ImplicitActivity' with the same action:
<activity
android:name=".TESTActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".ImplicitActivity">
<intent-filter>
<action android:name="com.myapp.test.myimplicit_action" />
</intent-filter>
</activity>
Both the activities TESTActivity and ImplicitActivity are in the same application under same package. Still my ImplicitActivity activity is not getting called.
I have figured out the problem. Posting the answer for the others facing the same problem.
We need to add Default Category in order to make Implicit intents work. So here is the correct manifest entry for the same activity :
<activity
android:name=".TESTActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".ImplicitActivity">
<intent-filter>
<action android:name="com.myapp.test.myimplicit_action" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
I keep getting "ActivityNotFoundException: Unable to find explicit activity class ... " when using Eclipse's emulator to call the activity of another application from an application. Perhaps the problem maybe related to I am not able to download to/find both applications at the same time when I click on "Manage Applications" in Settings. This is the first project I need to call the activity of another application. But I am not sure the code is correct either. Please help me determine if there are errors in the code snippets I present below. It is hinted that I can set the action field of the intent to achieve the objective but have not found learning material for this. I learned about using the setComponent method in the calling app and to add android:export to the called activity's AndroidManifest.xml. Thanks in advance!
Calling app's relevant source code:
Intent intent = new Intent();
intent.setComponent(new ComponentName("com.MyPackage", om.MyPackage.Activity1));
startActivity(intent);
Calling app's relevant AndroidManifest.xml :
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name=".MainActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".Activity1">
<intent-filter>
<action android:name="com.MyPackage.Activity1" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
Relevant code of AndroidManifest.xml of the activity of another application
<activity android:name=".Activity1" android:exported = "true">
<intent-filter>
<action android:name="com.MyPackage.Activity1" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
Firstly point out that you're trying to start Activity in Application2 from Activity in Application1
You have to give them separate namespaces
both applications now have com.MyPackage.* prefix
OR use names Activity1 and Activity2
So you will have
com.MyPackage1.Activity1
// and
com.MyPackage2.Activity1
Then you can use this code, to start Activity1 in MyPackage2 from MyPackage1.
// in file com.MyPackage1.Activity1
Intent intent = new Intent();
intent.setComponent(new ComponentName("com.MyPackage2", "com.MyPackage2.Activity1"));
startActivity(intent);
And your AndroidManifest.xml files should look like this:
first
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name="com.MyPackage1.Activity1"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
second
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name="com.MyPackage2.Activity1"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
see related SO question:
How to start activity in another application?
My problem is thus; I am new to programming on the ANDROID platform and have a 'working' application that piggy-backs on the API-Docs example. I wish it to launch three tabs one containing a list of reports, one a form to file a report and the last to show the geo-located reports. It doesn't appear as a separate application, it instead appears as a list to be launched by the API-Docs example. Below is my manifest code...
<activity android:name=".HelloFlamingos">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.SAMPLE_CODE" />
</intent-filter>
</activity>
<activity android:name=".Controls2" android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.TAB" />
</intent-filter>
</activity>
<activity android:name=".List1" android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.TAB" />
</intent-filter>
</activity>
<activity android:name=".ReviewTab" android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.TAB" />
</intent-filter>
</activity>
</application>
<uses-sdk android:minSdkVersion="3" />
HelloFlamingos is the initial page that I wish to be displayed, I realise that the intents for this are wrong, have thought about using category: VIEWS, action: DEFAULT, however is seemingly unwilling to work. Thanks!
In what context is the activity started? If you're looking to have the HelloFlamingos activity the first displayed from the Android OS, you should change its category in the manifest to category.LAUNCHER.
If you're looking to start the activity from elsewhere in your app, create an Intent which matches what you've specified (category.SAMPLE_CODE) and use startActivity or startActivityForResult.
I am confirming about creating activity.
My Manifest.xml is like this :
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name=".FirstActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".SecondActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".ThirdActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
You can see property action android:name= property is "android.intent.action.MAIN" and
category android:name= is "android.intent.category.LAUNCHER" for all activities.
When the application starts up, it calls FirstActivity.
Then calls useless Activity such as ThirdActivity or SecondActivity.
In this case, is my manifest.xml correct?
Or, do I need to set another property to Second and Third activity?
If so, what is that?
I wonder manifest.xml file is right for my case.
Please advise.
Try this config:
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name=".FirstActivity" android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".SecondActivity" android:label="#string/app_name">
<intent-filter>
</intent-filter>
</activity>
<activity android:name=".ThirdActivity" android:label="#string/app_name">
<intent-filter>
</intent-filter>
</activity>
Think of an Intent as message used to start an Activity to do something. So I can create an Intent to view a web page and an application with an Activity which knows how to view a web page - most likely the browser - can intercept his Intent as act on it.
You tell Android which Activities can act on which Intents using the <intent-filter> part of your Manifest.
The MAIN Intent is a special one. This is sent to an application when it is launched and basically it says "Go!" So the Activity which shoud be displayed first needs to intercept this by having a correctly defined <intent-filter>.
As you had all three Activities with MAIN in their filter they all responded to the request to start your application. So you should have that <intent-filter> only for FirstActivity.
One of the other problems with using
<category android:name="android.intent.category.LAUNCHER" /> for more than one activity is that the Phone's launcher menu will display more than one icon...
From the docs:
CATEGORY_LAUNCHER The activity can
be the initial activity of a task and
is listed in the top-level application
launcher.