Question

For some reason that I don’t understand, when I create my SurfaceView from an XML layout the surface is cleared every refresh. But if I just initalize it in code without the XML the drawn surface is retained.

If I initialize the SurfaceView like this it is drawn blank every refresh:

app = (App) findViewById(R.id.app);
app.setActivity(this);

If I initialize the SurfaceView like this the surface’s drawing is retained every refresh:

app = new App(this);
setContentView(app);
app.setActivity(this);

Here is the XML layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/container"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@android:color/black"
    android:clickable="true">
        <com.threedtopo.someapp.android.app
            android:id="@+id/app"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@android:color/black"
            android:clickable="true" />
</LinearLayout>

Any insight would be appreciated, thanks!

Edit: This is how the root view is being initialized in the first example:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" android:layout_height="fill_parent">
        <LinearLayout
            android:layout_alignParentTop="true"
            android:layout_height="wrap_content"
            android:layout_width="wrap_content">
            <!-- <TextView -->
            <EditText
            android:id="@+id/hidden_text"
            android:inputType="textLongMessage"
            android:autoText="true"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" 
            android:editable="true"
            android:visibility="gone"
            android:focusable="true"
            android:focusableInTouchMode="true"
            />
        </LinearLayout>
    <ViewSwitcher
        android:id="@+id/switcher"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >
        <ImageView
            android:id="@+id/splash"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/splashscreen" />
        <com.threedtopo.someapp.android.app             android:id="@+id/app"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@android:color/white"
            android:clickable="true" />
    </ViewSwitcher> 
    <LinearLayout
        android:id="@+id/keyboard_layout"
        android:layout_alignParentBottom="true"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content">
        <android.inputmethodservice.KeyboardView
            android:id="@+id/keyboard"
            android:visibility="gone"
            android:focusable="true"
            android:focusableInTouchMode="true"
            android:layout_height="wrap_content"
            android:layout_width="wrap_content"
            android:layout_weight="0" />
    </LinearLayout>
</RelativeLayout>

Answer 1

Thanks to harism this has been solved. Apparently setting the background property in the XML file causes the SurfaceView to be cleared each draw.