implement DrawableContainer and copy StateListDrawable from AOSP

src/api-impl/android/graphics/drawable/DrawableContainer.java

@@ -1,13 +1,61 @@
 package android.graphics.drawable;
 
-import android.graphics.Canvas;
+import android.content.res.Resources;
 
 public class DrawableContainer extends Drawable {
 
-	@Override
-	public void draw(Canvas canvas) {
-		// TODO Auto-generated method stub
-		throw new UnsupportedOperationException("Unimplemented method 'draw'");
+	private DrawableContainerState state;
+	private int curIndex = -1;
+
+	protected native long native_constructor();
+	protected native void native_selectChild(long container, long child);
+
+	public DrawableContainer() {
+		paintable = native_constructor();
+	}
+
+	public boolean selectDrawable(int idx) {
+		if (idx >= 0 && idx < state.childCount && idx != curIndex && state.drawables[idx] != null) {
+			curIndex = idx;
+			native_selectChild(paintable, state.drawables[idx].paintable);
+			return true;
+		}
+		return false;
+	}
+
+	protected void setConstantState(DrawableContainerState state) {
+		this.state = state;
+	}
+
+	public static class DrawableContainerState {
+
+		private Drawable drawables[] = new Drawable[10];
+		private int childCount = 0;
+
+		public DrawableContainerState(DrawableContainerState orig, DrawableContainer owner, Resources res) {
+		}
+		
+		public int getCapacity() {
+			return drawables.length;
+		}
+
+		public int getChildCount() {
+			return childCount;
+		}
+
+		public int addChild(Drawable dr) {
+			if (childCount >= drawables.length) {
+				growArray(drawables.length, drawables.length * 2);
+			}
+			drawables[childCount] = dr;
+			return childCount++;
+		}
+
+		public void growArray(int oldSize, int newSize) {
+				Drawable[] newDrawables = new Drawable[newSize];
+				System.arraycopy(drawables, 0, newDrawables, 0, oldSize);
+				drawables = newDrawables;
+		}
 	}
 	
 }