我如何从片段2返回片段1？ 如图所示

Question

Fragment 1 is opened by navigation drawer and fragment 2 is opened by fragment 1 now I want to go back from fragment 2 to fragment 1 with back button as shown in picture and wanna hide drawer icon from fragment 2

Answer 1

You can use a click or swipe event

get the instance of your second fragment

SecondFragment fragment = new SecondFragment();
fragmentManager.beginTransaction().replace(R.id.first_container, fragment).commit();

Answer 2

You can do this by adding Activity and then first call activity from previous fragment then call your desired fragment in activity and finally add back button on the activity.

public class DetailActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_detail);
       /* ActionBar actionBar = getSupportActionBar();
        actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
        actionBar.setCustomView(R.layout.header);
        actionBar.setDisplayHomeAsUpEnabled(true); */
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        toolbar.setNavigationIcon(R.drawable.back);
        setSupportActionBar(toolbar);
         getSupportActionBar().setTitle("Smart Take Away");
      //  getSupportActionBar().setDisplayShowTitleEnabled(false);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        if (toolbar != null) {
            toolbar.setNavigationOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    onBackPressed();
                }
            });
        }
     //   Bundle extras = getIntent().getExtras();

        if (savedInstanceState == null) {
            try {
                android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
                android.support.v4.app.FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                DetailedListFragment fragment = new DetailedListFragment();
            //    fragment.setArguments(extras);
                fragmentTransaction.replace(R.id.detailfragment, fragment);
                fragmentTransaction.commit();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    @Override
    public void onBackPressed() {
        super.onBackPressed();

    }
}