Display toast in fragment getActivity() vs mActivity reference

Question

Is calling the method getActivity() once in my fragment and saving the reference in mActivity better than calling getActivity() every time I want to show a toast message?

Toast.makeText(mActivity, text, duration).show();

vs.

Toast.makeText(getActivity(), text, duration).show();

Answer 1

getActivity() should be preferred for 2 reasons:
1) Memory leak prevention
Having a variable mActivity lying around opens up opportunities for memory leak eg mistakenly set the variable as static , makes it easy and convenient to reference the activity in some running anonymous AysncTask

2) Correct nature of fragment-activity relationship
Fragments can be attached or detached at many point of times. Therefore, getting a reference of the activity hosting the current fragment should be on a on-demand basis . Having a mActivity variable means you need to set and unset it correctly.

Take note that what Toast requires here is a Context object so it's not necessarily the activity that is required here. An application context object would also suffice

Answer 2

Fragment wise both are same

First one

Activity mActivity = getActivity();

@Override
public void onClick(View arg0) {

Toast.makeText(**mActivity**,"Text!",Toast.LENGTH_SHORT).show();

}

Second one

use Directly like this

    Toast.makeText(getActivity(),"Text!",Toast.LENGTH_SHORT).show();

Answer 3

if you just need a Context or Activity, no difference. but if you want to access some method or field inside the parent activity, you would better saving the reference in mActivity.

Answer 4

如果您只想让上下文显示Toast消息并且很难获得对Activity的引用，则可以使用getApplicationContext()代替。