我有MainActivity的Android片段生命周期和FragmentManager.add()
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportFragmentManager()
.beginTransaction()
.add(R.id.fragment_container, AFragment.newInstance(75))
.commit();
}
@Override
public void onBackPressed() {
if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
getSupportFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
另外,我有AFragment
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_a, container, false);
view.findViewById(R.id.show_b_btn).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
AppCompatActivity appCompatActivity = (AppCompatActivity) getActivity();
appCompatActivity.getSupportFragmentManager()
.beginTransaction()
.add(R.id.fragment_container, BFragment.newInstance())
.addToBackStack("B")
.commit();
}
});
return view;
}
BFragment只是一个空片段。
而且我有以下片段生命周期的输出:
Open the App:
A - onCreateView
A - onStart
A - onResume
Click R.id.show_b_btn on AFragment:
B - onStart
B - onResume
Click back button:
B - onPause
B - onStop
Close the App:
A - onPause
A - onStop
所以,问题是为什么AFragment不调用的onPause当我点击ShowBFragment为什么AFragment不调用的onResume当我点击后退按钮?
我认为这是因为我使用.add()和BFragment只覆盖了AFragment,所以当片段可见时,AFragment也“生活”,对吗?
是的,你是对的。因为你使用.add()和BFragment只是覆盖了AFragment,所以AFragment在“BFragment”可见时也“活着”。 –
很酷,谢谢 –