Android switch Fragments in the new design support navigation drawer

问题

how can I switch Fragments in the new design support navigation drawer? I found example codes on the Cheesesquare Github on how to switch fragments using the TabLayout, but not the navigation drawer. Is that the same? I also would not like to recreate fragments when switching, but rather do it like the TabLayout where it retains the fragments instance and the fragment`s content is how the user left it.

回答1:

Write some code like this:

navigationView.setNavigationItemSelectedListener(
        new NavigationView.OnNavigationItemSelectedListener() {
    @Override
    public boolean onNavigationItemSelected(MenuItem menuItem) {
        menuItem.setChecked(true);
        mDrawerLayout.closeDrawers();
        switch (menuItem.getItemId()) {
            case R.id.your_menu_id: 
                getSupportFragmentManager().beginTransaction().replace(R.id.fragment, getFragment(), "SET_A_TAG").addToBackStack("SET_A_TAG").commit();
                break;
        }
        return true;
    }
});

private YourFragment getFragment() {
    YourFragment f = getSupportFragmentManager().findFragmentByTag("SET_A_TAG");
    if (f == null) {
        f = new YourFragment();
    }
    return f;
}

回答2:

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/drawer_layout"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:fitsSystemWindows="true">

<include layout="@layout/include_list_viewpager"/>

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@id/fragmentContainer"/>

<android.support.design.widget.NavigationView
    android:id="@+id/nav_view"
    android:layout_height="match_parent"
    android:layout_width="wrap_content"
    android:layout_gravity="start"
    android:fitsSystemWindows="true"
    app:headerLayout="@layout/nav_header"
    app:menu="@menu/drawer_view"/>

Something like this?

来源：https://stackoverflow.com/questions/30816892/android-switch-fragments-in-the-new-design-support-navigation-drawer