Fragment is not being replaced but put on top of t

Question

Activity:

FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();

Fragment1 fragment = new Fragment1();
Fragment2 fragment2 = new Fragment2();

transaction.replace(R.id.Fragment1, fragment);
transaction.addToBackStack(null);
transaction.commit();

FragmentTransaction transaction2 = getSupportFragmentManager().beginTransaction();
transaction2.replace(R.id.Fragment1, fragment2);
transaction2.addToBackStack(null);
transaction2.commit();

Code in the view:

<fragment
    android:id="@+id/Fragment1"
    android:name="com.landa.fragment.Fragment1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_below="@+id/include1" /> 

The problem is, the content doesn't really get replaced - it gets put on top (so it overlaps).

When I click back, the first fragment gets shown properly (without the second), but initially both are visible (I want only the last one to be visible).

What am I missing here?

Answer 1

Use a container instead of using fragment

<FrameLayout
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="Hello World!" />

Now in MainActivity

if(condition)
    getFragmentManager().beginTransaction().replace(R.id.container,new FirstFragment()).commit();                    
else
    getFragmentManager().beginTransaction().replace(R.id.container, new SecondFragment()).commit();

Please note that your fragment class should import 'android.app.Fragment' Make sure, that you use "support.v4" or the "original" implementations and do not mix them. I was getting this problem because I had mixed them.

Answer 2

You are doing two things wrong here:

1. You cannot replace a fragment that is statically placed in an xml layout file. You should create a container (e.g. a FrameLayout) in the layout and then add the fragment programatically using FragmentTransaction.

2. FragmentTransaction.replace expects the id of the container that contains the fragment and not the id of the fragment as the first parameter. So you should pass the first argument as the id of the container that you added the first fragment to.

You can refer to this link for more details.

Answer 3

I also had the same issue, but it was because I had not changed the background color of the fragment that I was trying add to my framelayout.

Try doing this, with layout_height and layout_width set to match_parent

Answer 4

I had a similar problem but my issue was that I was using two different Fragment managers: One from getSupportFragmentManager() and one from getFragmentManager(). If I added one fragment with the SupportFragmentManager and then tried replacing the fragment with the FragmentManager, the fragment would just get added on top. I needed to change the code so that the same FragmentManager would be used and that took care of the issue.

Answer 5

I had the same problem and saw all the answers, but none of them contained my mistake! Before trying to replace the current fragment, I was showing the default fragment in the xml of the container activity like this:

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

    <fragment
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:name="....ShopFragment"
        android:id="@+id/fragment"
        tools:layout="@layout/fragment_shop" />
</FrameLayout>

after that, although i was passing the FrameLayout to the fragmentTransaction.replace() but i had the exact problem. it was showing the second fragment on top of the previous one.

The problem fixed by removing the fragment from the xml and showing it programmatically in the onCreate() method of the container activity for the default preview on the start of the program like this:

    fragmentTransaction = getFragmentManager().beginTransaction();
    fragmentTransaction.replace(R.id.fragment_frame_layout,new ShopFragment());
    fragmentTransaction.addToBackStack(null);
    fragmentTransaction.commit();

and the container activity xml:

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

Answer 6

You can clear backStack before replacing fragments:

    FragmentManager fm = getActivity().getSupportFragmentManager();

    for (int i = 0; i < fm.getBackStackEntryCount(); i++) {
        fm.popBackStack();
    }

    // replace your fragments