FragmentStateManager
An Android library that holds fragment states for BottomNavigationView. Saves fragment back stack even after activity rotation. Implementation derived from FragmentStatePagerAdapter.
Installation
Add Jitpack to project level gradle file
allprojects {
repositories {
maven {
url "https://jitpack.io"
}
}
}
Then add library to module level gradle file
dependencies {
compile 'com.github.okaybroda:FragmentStateManager:1.+'
}
Usage
Create a FragmentStateManager instance in the OnCreate function of your Activity
FragmentStateManager fragmentStateManager; @Override protected void onCreate(Bundle savedInstanceState) {
// ... your code ...
FrameLayout content = findViewById(R.id.content);
fragmentStateManager = new FragmentStateManager(content, getSupportFragmentManager()) {
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new MainFragment();
case 1:
return new SearchFragment();
case 2:
return new MeFragment();
}
}
}
;
}
To change current fragment, call
fragmentStateManager.changeFragment(0);
// 0 is the index of the fragmentIntegration with BottomNavigationView
Add item selected listener
navigation.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
int position = getNavPositionFromMenuItem(item);
if (position != -1) {
fragmentStateManager.changeFragment(getNavPositionFromMenuItem(item));
return true;
}
return false;
}
}
);
(Optional) Add item reselected listener. This will reset the fragment to it's original state
navigation.setOnNavigationItemReselectedListener(new BottomNavigationView.OnNavigationItemReselectedListener() {
@Override
public void onNavigationItemReselected(@NonNull MenuItem item) {
int position = getNavPositionFromMenuItem(item);
if (position != -1) {
fragmentStateManager.removeFragment(position);
fragmentStateManager.changeFragment(position);
}
}
}
);