add support for custom Java Drawables

This is made possible, by adding a second Canvas implementation which
can be used to render directly to GdkSnapshot objects

For now the only implemented method is drawBitmap(), this is already
enough to make VectorDrawableCompat functional

src/api-impl/android/graphics/Canvas.java

@@ -81,7 +81,7 @@ public class Canvas {
 	 * @param px The x-coord for the pivot point (unchanged by the rotation)
 	 * @param py The y-coord for the pivot point (unchanged by the rotation)
 	 */
-	public final void rotate(float degrees, float px, float py) {
+	public void rotate(float degrees, float px, float py) {
 		native_rotate_and_translate(skia_canvas, widget, degrees, px, py);
 	}
 	// ---

src/api-impl/android/graphics/GskCanvas.java

@@ -0,0 +1,74 @@
+package android.graphics;
+
+/**
+ * GskCanvas:
+ *   - implements Canvas for onscreen rendering inside GTKs snapshot function
+ */
+public class GskCanvas extends Canvas {
+	private long snapshot;
+
+	public GskCanvas(long snapshot) {
+		System.out.println("GskCanvas(" + snapshot + ")");
+		this.snapshot = snapshot;
+	}
+
+	@Override
+	public int save() {
+		System.out.println("GskCanvas.save()");
+		return -1;
+	}
+
+	@Override
+	public void restore() {
+		System.out.println("GskCanvas.restore()");
+	}
+
+	@Override
+	public void translate(float dx, float dy) {
+		System.out.println("GskCanvas.translate(" + dx + ", " + dy + ")");
+	}
+
+	@Override
+	public void rotate(float degrees) {
+		System.out.println("GskCanvas.rotate(" + degrees + ")");
+	}
+
+	@Override
+	public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint) {
+		native_drawBitmap(snapshot, bitmap.pixbuf, dst.left, dst.top, dst.width(), dst.height());
+	}
+
+	@Override
+	public void drawPath(Path path, Paint paint) {
+		System.out.println("GskCanvas.drawPath(" + path + ", " + paint + ")");
+	}
+
+	@Override
+	public void drawRect(float left, float top, float right, float bottom, Paint paint) {
+		System.out.println("GskCanvas.drawRect(" + left + ", " + top + ", " + right + ", " + bottom + ", " + paint + ")");
+	}
+
+	@Override
+	public void rotate(float degrees, float px, float py) {
+		System.out.println("GskCanvas.rotate(" + degrees + ", " + px + ", " + py + ")");
+	}
+
+	@Override
+	public void drawText(String text, float x, float y, Paint paint) {
+		System.out.println("GskCanvas.drawText(" + text + ", " + x + ", " + y + ", " + paint + ")");
+	}
+
+	@Override
+	public void drawLine(float startX, float startY, float stopX, float stopY, Paint paint) {
+		System.out.println("GskCanvas.drawLine(" + startX + ", " + startY + ", " + stopX + ", " + stopY + ", " + paint + ")");
+	}
+
+	@Override
+	public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) {
+		Rect src = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
+		Rect dst = new Rect((int)left, (int)top, (int)left + bitmap.getWidth(), (int)top + bitmap.getHeight());
+		drawBitmap(bitmap, src, dst, paint);
+	}
+
+	protected native void native_drawBitmap(long snapshot, long pixbuf, int x, int y, int width, int height);
+}

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

@@ -28,7 +28,9 @@ public class Drawable {
 	private int[] mStateSet = new int[0];
 	public long paintable;
 
-	public Drawable() {}
+	public Drawable() {
+		this.paintable = native_constructor();
+	}
 
 	public Drawable(long paintable) {
 		this.paintable = paintable;
@@ -180,4 +182,5 @@ public class Drawable {
 	}
 
 	protected static native long native_paintable_from_path(String path);
+	protected native long native_constructor();
 }

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

@@ -1,15 +1,7 @@
 package android.graphics.drawable;
 
-import android.graphics.Canvas;
-
 public class GradientDrawable extends Drawable {
 
-	@Override
-	public void draw(Canvas canvas) {
-		// TODO Auto-generated method stub
-		throw new UnsupportedOperationException("Unimplemented method 'draw'");
-	}
-
 	public void setColor(int color) {}
 
 	public void setCornerRadius(float cornerRadius) {}

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

@@ -1,6 +1,5 @@
 package android.graphics.drawable;
 
-import android.graphics.Canvas;
 import android.graphics.Rect;
 
 public class InsetDrawable extends Drawable {
@@ -9,12 +8,6 @@ public class InsetDrawable extends Drawable {
 		super();
 	}
 
-	@Override
-	public void draw(Canvas canvas) {
-		// TODO Auto-generated method stub
-		throw new UnsupportedOperationException("Unimplemented method 'draw'");
-	}
-
 	public boolean getPadding(Rect padding) { return false; }
 	
 }

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

@@ -1,15 +1,9 @@
 package android.graphics.drawable;
 
 import android.content.res.ColorStateList;
-import android.graphics.Canvas;
 
 public class RippleDrawable extends Drawable {
 
 	public RippleDrawable(ColorStateList colorStateList, Drawable drawable, Drawable drawable2) {}
 
-	@Override
-	public void draw(Canvas canvas) {
-		// TODO Auto-generated method stub
-		throw new UnsupportedOperationException("Unimplemented method 'draw'");
-	}
 }

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

@@ -1,6 +1,5 @@
 package android.graphics.drawable;
 
-import android.graphics.Canvas;
 import android.graphics.Paint;
 import android.graphics.drawable.shapes.Shape;
 
@@ -9,11 +8,5 @@ public class ShapeDrawable extends Drawable {
 	public ShapeDrawable(Shape shape) {}
 
 	public Paint getPaint() {return new Paint();}
-
-	@Override
-	public void draw(Canvas canvas) {
-		// TODO Auto-generated method stub
-		throw new UnsupportedOperationException("Unimplemented method 'draw'");
-	}
 	
 }