Android Fragments - 多项活动还是一项？

Question

I'm a new android "developer" and have a question about "Android Fragment - one vs. multiple activities".

While there are 2-3 questions on this topic, they are already a few years old.

For training, I wanted to create a simple app with an action bar and multiple fragments and i want to use the camera.

What is the best way to create something like this? One activity which manage all the fragments or multiple activities? Since i want to use the camera, it is probably easier to use multiple activities (camera intent etc...) - but i don't know - i'm new to android ;)

Are there any benefits to use more activities instead of one?

Answer 1

I always prefer the following setup:

1. A own Application - Class.
This gives you the availability to use and implement common patterns such as registry, eg
The application object can be retrieved in every activity via the getApplicationContext
-method and is singleton per nature. Also it's the only object that is guaranteed to
be existing through your application's lifecycle. This makes it a most suitable entry point for all sort of implementation details according to objects that need to be existing trough every part of your application.

2. Following 1. , I register both my Activity - objects and Fragment 's in this
application class. This allows additional cross - activity and cross - fragment
implementations.

I know that this approach seems to be rather monolithic and I wouldn't overuse concepts
like this, but it is handy in many cases, may it be reading additional application
configuration resources from the asset - directory or establishing database connections so and reuse them.
So that's where I instanziate my fragments and this kind of setup gives me full
flexibility and control over my application. Because of the of fragments I
tend to use them, and:

Answer 2

I think, one FragmentActivity holding other fragments will be good. I already have done a project, firing camera intents from fragments. You can fire intents (for result) and manage the fragment replacing in your FragmentActivity onActivityResult() function.

firing camera fragment.

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, TAKE_PICTURE);

//You fragment Activity.. When camera intent ends. onActivityResult() will be called.

public void onActivityResult(.......)
{
//check is it returning from camera, do whatever you want to do.
}