How to add a fragment to a layout of a DialogFragment?

问题

I am having a custom DialogFragment which contains a layout, some UI elements, and a Fragment holder layout. What I need to do is inflate a Content fragment into the holder layout and provide a navigation inside that. On clicking a button inside the added fragment the view will navigate to another view. The fragment will be replaced by another one in the same holder i.e. the contentFragment1 will show some data and on clicking a preview button there will replace contentFragment1 with contentFragment2. I read somewhere that you cannot replace a fragment hardcoded to the xml with another one. So I am trying to add the contentFragment1 to the viewholder from the onActivityCreated() of the dialog fragment. But I am getting an error that the resource pointed by R.id.fragmentHolder not found. What could be the possible reason?

Here is my code for the DialogFragment:

public class MyDialog extends DialogFragment {
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    Dialog customDialog = new Dialog(getActivity());
    customDialog.getWindow().requestFeature(Window.FEATURE_NO_TITLE);
    customDialog.setContentView(R.layout.reports_dialog);
    return customDialog;
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    android.app.FragmentTransaction fragmentTransaction =getFragmentManager().beginTransaction();
    fragmentTransaction.add(R.id.myFragmentHolder, new ReportsListFragment());
    fragmentTransaction.commit();
    super.onActivityCreated(savedInstanceState);
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="400dp"
    android:background="@android:color/transparent" >


    <TextView
        android:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:text="This is my header text view for the Dialog"
        android:textSize="18sp" />

<RelativeLayout
    android:id="@+id/myFragmentHolder"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_below="@+id/headerlayout" >

</RelativeLayout>

回答1:

After trying a lot, I came to a conclusion that onCreateDialog() doesn't have a view, it just sets a view on calling setView().

That is why on adding dynamic(framelayout tag) or static fragment(fragment tag) in the layout of the dialogfragment gives no parent view or duplicate id error.

To achieve the above, one should use onCreateView with a framelayout tag which can be inflated dynamically. Title and alert buttons are then added to the layout.

回答2:

R.id.myFragmentHolder is inflated to the dialog's layout, and getFragmentManager() returns the manager for the activity, so it can't find the view.

With nested fragments in API level 17 you can use getChildFragmentManager().

回答3:

Just be sure that the reports_dialog layout containts a layout whose id myFragmentHolder like this one

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

回答4:

Just for reference here, as Brandon mention the correct answer is to use the getChildFragmentManager(), keeping in mind, that android will also restore the state of fragments.

The correct code, to add your first fragment, is:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // if the saved instance isn't null, the fragment state will be restored by android
    if (savedInstanceState == null) {
        getChildFragmentManager().beginTransaction().add(R.id.myFragmentHolder, new ReportsListFragment()).commit();
    }
}

after the view has been added. Later use replace if only one fragment should be shown at the same time.

I would also recommend to call transaction.addToBackStack(null); if the Android back button should be supported.

回答5:

id of fragment holder in layout is fragmentHolder and you are using myFragmentHolder in code try to replace this by:

 fragmentTransaction.add(R.id.fragmentHolder, new ReportsListFragment());

来源：https://stackoverflow.com/questions/21258228/how-to-add-a-fragment-to-a-layout-of-a-dialogfragment

标签

android

android-layout

android-fragments

android-dialogfragment

fragmenttransaction