Question

This one is weird. I have a list view that is a part of Relative Layout. I have set a background to this Relative Layout and made list view background as transparent.

Now, everything was working great till this morning. I could see the whole screen covered with my custom background even if there is just one row in my list view.

Then, I got update on Verizon Motorola Droid X for 2.3.3 (it was 2.2 before). Once it was updated, I started my app again and now here is what happens.

If my list view has only one row, I see a white area below it and not my custom background.
But if it has say 100 rows and thus covers the whole screen I won’t see that weird white background. My relative layout has width and height set to “fill_parent”.

I have posted my XML at the bottom. Has anyone else faced this problem or I am making some really stupid mistake.

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:background = "@drawable/background" 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <ListView   android:id = "@+id/listQueue"
                android:layout_width = "fill_parent"
                android:layout_height = "fill_parent"
                android:layout_below = "@id/homeScreenBanner"
                android:background="@android:color/transparent"
                android:divider="@drawable/separator"
                android:scrollingCache="false"/>
</RelativeLayout>

EDIT:

I think I have found the solution to this problem:

Changed the layout_height attribute to wrap_content and it worked like a charm. 🙂

Following the changed line.
android:layout_height = "wrap_content"

Answer 1

I wrote a class that can be used in Android 2.1/2 that will do the right thing in 2.3 using reflection with ListViews:

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import android.content.Context;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.util.AttributeSet;
import android.widget.ListView;

public class TransparentListView extends ListView {

    private void makeTransparent() {
        if (Build.VERSION.SDK_INT >= 9) {
            try {

                Method overscrollFooterMethod = 
                    TransparentListView.class.getMethod("setOverscrollFooter", new Class[] {Drawable.class});
                Method overscrollHeaderMethod = 
                    TransparentListView.class.getMethod("setOverscrollHeader", new Class[] {Drawable.class});


                try {
                    overscrollFooterMethod.invoke(this, new Object[] {null});
                    overscrollHeaderMethod.invoke(this, new Object[] {null});
                } catch (IllegalArgumentException e) {
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                } catch (InvocationTargetException e) {
                    e.printStackTrace();
                }
            } catch (SecurityException e) {
                e.printStackTrace();
            } catch (NoSuchMethodException e) {
                e.printStackTrace();
            }
        }
    }

    public TransparentListView(Context context) {
        super(context);
        this.makeTransparent();
    }

    public TransparentListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        this.makeTransparent();
    }

    public TransparentListView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        this.makeTransparent();
    }
}

Use it in XML as follows:

<com.myapp.TransparentListView android:id="@android:id/list"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:transcriptMode="alwaysScroll"
    android:layout_weight="1"
    android:dividerHeight="0dip"
    android:divider="#00000000"
    android:cacheColorHint="#00000000"
/>