findViewById() 在片段中返回 null

Question

So I think I have gone through all the answers here on stackoverflow for this problem. However, noone of them have helped. I am currently working with the camera2 example by Google trying to add an imageview "imageOverlay" that covers the whole screen. However, imageview is always null when trying to retrieve it. Any idea what I am missing?

Edit:

What has been tried:

• Moving the ImageView in the camera_fragment.xml into the FrameLayout so that I can retrieve it just like the Button. This seemed like the best idea to make it an overlay.
• Using getView()
• Using getActivity()
• Cleaning and rebuilding.
• Using View view = inflater.inflate(R.layout.camera_fragment, null);

Camera_Activity xml:

    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:id="@+id/container"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:background="#000"
   tools:context="com.irg.hig.imageregistrationgame.CameraActivity"
/>

camera_fragment.xml:

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <com.irg.hig.imageregistrationgame.CameraTextureView
        android:id="@+id/texture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true" />

    <ImageView
        android:id="@+id/imageOverlay"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:alpha="0.5" />

    <FrameLayout
        android:id="@+id/control"
        android:layout_width="match_parent"
        android:layout_height="112dp"
        android:layout_alignParentBottom="true"
        android:layout_alignParentStart="true"
        android:background="@color/control_background">

        <Button
            android:id="@+id/picture"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="@string/picture" />

        <ImageButton
            android:id="@+id/info"
            android:contentDescription="@string/description_info"
            style="@android:style/Widget.Material.Light.Button.Borderless"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical|right"
            android:padding="20dp" />

    </FrameLayout>
</RelativeLayout>

CameraFragment.java:

    @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.camera_fragment , container, false);
    imageView = (ImageView) view.findViewById(R.id.imageOverlay);

    return view;
}

    @Override
public void onViewCreated(final View view, Bundle savedInstanceState) {
    view.findViewById(R.id.picture).setOnClickListener(this);
    view.findViewById(R.id.info).setOnClickListener(this);
    mTextureView = (CameraTextureView) view.findViewById(R.id.texture);
    //imageView = (ImageView) view.findViewById(R.id.imageOverlay);
}

Answer 1

The problem was that there was a second xml file in layout-v21 that was used and not the one in the Layout folder that I was trying to change. Thanks to everyone that tried to help, it was appreciated immensely.

Answer 2

Try this.

LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View view = inflater.inflate(R.layout.your_layout, null);

Answer 3

Try to replace : View view = inflater.inflate(R.layout.camera_fragment , container, false);

by View view = inflater.inflate(R.layout.camera_fragment, null);