Start Activity Using Custom Action

Question

I am looking to start an activity in my app using a custom action. I have found a few answers but everything I try it throws java.lang.RuntimeException saying N

Answer 1

I think you are creating your intent wrong. Try like this:

String CUSTOM_ACTION = "com.example.foo.bar.YOUR_ACTION";

//Intent i = new Intent(this, FeedBackActivity.class);  // <--- You might need to do it this way.
Intent i = new Intent();
i.setAction(CUSTOM_ACTION);

startActivity(i);

Answer 2

I think what you need is to add a default category to your intent-filter, eg.

<activity
    android:name=".FeedbackActivity" >  
    <intent-filter>
        <action android:name="com.example.foo.bar.YOUR_ACTION" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

see this answer for more info.

Answer 3

Just add and intent-filter category as Default.

Implicit intent works perfectly and in many cases its better to use a implicit intent with Intent-action to call a service/Activity than using class-name.

Before startActivty() / startService() with proper context you cane use this method 'queryIntentActivities(Intent intent, int flags)' from package manager class.

It helps the ActivityManager (responsible for launching activities) to check whether the Android system is getting any match with you Intent.

If it doesn't it returns a list size 0 or else >0.

By this you can also check if your app is getting the call,and in this case even if your app is not installed / has got some problem, it will not crash but will throw a warning in Log. Users will face no big trouble apart from app not being launched.

(users will never forgive you if tour app crashes).

Hope this will help !!! Happy Coding. :)

Answer 4

I faced the same problem when trying to launch the activity residing in the dynamic feature module and starting through action String as the Activity is not resolvable by name at compile time. So I set the action but the activity crashes every time (No Activity found to handle intent bla bla.. ) until I set the correct package name.

Context c = getApplicationContext();// flag would be require Calling startActivity() from outside of an Activity  context requires the FLAG_ACTIVITY_NEW_TASK flag
Intent i = new Intent(action_string);
i.setPackageName(context.getPackageName());//this did the trick actually
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);

In the Manifest : add catrgory default to the intent filters from google docs:

<category android:name="android.intent.category.DEFAULT"/>

Note: In order to receive implicit intents, you must include the CATEGORY_DEFAULT category in the intent filter. The methods startActivity() and startActivityForResult() treat all intents as if they declared the CATEGORY_DEFAULT category. If you do not declare it in your intent filter, no implicit intents will resolve to your activity.