SVG image not visible in android 3.0+ with same code

Question

I have a test app where I have got a ListView with an item which contains two images on it.

As you can see in the API 17 device does not display the play button (SVG image) while the API 10 device does that. How can I fix that?

My layout file:

<?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="match_parent" >

    <ImageView
        android:id="@+id/background"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:scaleType="centerCrop" />

    <ImageView
        android:id="@+id/forceground"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true" />

</RelativeLayout>

Here is my basic code where I set the images:

View preview = inflater.inflate(R.layout.list_video_preview, parent, false);
ImageView background = (ImageView)preview.findViewById(R.id.background);
ImageView forceground = (ImageView)preview.findViewById(R.id.forceground);
PictureDrawable play = SVGParser.getSVGFromResource(parent.getResources(), R.raw.play_blue).createPictureDrawable();
forceground.setImageDrawable(play);

The SVG paser is from svg-android.

Answer 1

The problem is the hardware acceleration. The solution is to use bitmaps instad of drawables. For fixing that I added this function to the SVG.java which returns a BitmapDrawable:

public BitmapDrawable createBitmapDrawable(Context context) {
    Bitmap bitmap = Bitmap.createBitmap(picture.getWidth(), picture.getHeight(), Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    PictureDrawable drawable = new PictureDrawable(picture);
    drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
    drawable.draw(canvas);
    return new BitmapDrawable(context.getResources(), bitmap);
}

Answer 2

The problem with your solution is that you are losing all the drawing information when converting it to a Bitmap. In your case it doesn't apply, but if you needed to support Zooming and Panning, you would be scaling and resizing a Bitmap and would get pixelated graphics. Additionally it's much more inefficient to draw a Picture into a Bitmap which will then be drawn by the View that contains it.

I had the same problem you experienced and solved it by turning off hardware acceleration only on the view that will draw the Picture:

view.setLayerType(View.LAYER_TYPE_SOFTWARE, null);

However setLayerType is only supported since API 11. So use this method instead:

public static void setHardwareAccelerated(View view, boolean enabled){
    if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
        if(enabled)
            view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
        else view.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
    }
}