Question

Is there any functional difference between using the intent-filter

Intent myIntent = new Intent("com.this.that.MYACT");
myIntent.setPackage("com.this.that");

vs.

Intent myIntent = new Intent(context, MyActivity.class);
myIntent.setPackage("com.this.that");

Is one of these

• safer?
• faster?
• some other advantage?

Or is there no difference at all?

TIA

Answer 1

The answer is: use whatever Intent structure that the author of the “external app” told you to use, or use getLaunchIntentForPackage() on PackageManager to get an Intent suitable for generically starting up the “external app”.

I’ve tested them both in both circumstances, and don’t see any difference in behavior.

That is only because com.this.that.MyActivity happens to have an <intent-filter> or has specifically marked itself is as being exported. By default, activities are not exported, and no Intent can be used to launch them from a third-party app.

Also, your code will not even compile, as MyActivity is not in your project (it is in the “external app”), and so MyActivity.class does not exist. The only way it will compile (and work successfully) is if both your app and the “external app” happen to have the same activity class in the same Java package, which is unlikely.

safer?

The author of the “external app” should be using Intent actions (your first scenario), as it is easier to keep those consistent in the face of refactoring code. Your second approach will break if the author of the “external app” refactors their code into sub-packages, renames the activity class, etc. Basically, the action name becomes the public API, if you will, of the activity (along with any documented extras). This is why you see the Android SDK use this approach exclusively for its own documented and supported activities.

faster?

There might be a tiny speed increase for the second one, but we’d be talking microseconds per startActivity(), which is not worth worrying about.