android-canvas

I am working on an Android project similar to a scratch card. I have two layers in RelativeLayout. Bottom layer contains an ImageView, and top layer contains a SurfaceView. The problem is the display stays black and doesn't show the ImageView even if I set canvas.drawColor(Color.TRANSPARENT) . What should I do if I want to scratch and erase the part of SurfaceView and reveal the ImageView below? Thanks in advance. And I am sorry for the bad English. Here's my layout: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android

I am drawing an Rectangle with outside of rectangle fill. I tried some of this. But cant get the perfect one what i expected. This is what i expected. I tried Point pTopLeft = new Point(); Point pBotRight = new Point(); pTopLeft.x = 100; pTopLeft.y = 100; pBotRight.x = canvas.getWidth() - 100; pBotRight.y = canvas.getHeight() - 100; Rect above = new Rect(0, 0, canvas.getWidth(), pTopLeft.y); paint.setColor(Color.parseColor("#77000000")); canvas.drawRect(above, paint); Rect left = new Rect(0, pTopLeft.y, pTopLeft.x, pBotRight.y); paint.setColor(Color.parseColor("#77000000")); canvas.drawRect

I am working with canvas in android. i want to draw shapes on canvas which fits in every screen. if screen size is 320 * 240 then height & width with is 90 * 90 but if screen_size is > 320 * 240 then it should increase accordingly. Suppose screen_size = 1280 * 800 then how much it should increase I don't know what to do for this Code is Like int fixHeight = 240, fixWidth = 320; Paint paint; paint = new Paint(); paint.setColor(Color.GREEN); DisplayMetrics displaymetrics = new DisplayMetrics(); getWindowManager().getDefaultDisplay().getMetrics(displaymetrics); int height = displaymetrics

I am working on creating a custom view where a user can select an angle. Below is an example of what the end result should look like: I am achieving this with the following code: mPaint.setColor(Color.BLACK); canvas.drawCircle((int) (mSize.right / 2), (int) (mSize.bottom / 2), mWidthOutside, mPaint); mPaint.setColor(Color.LTGRAY); canvas.drawCircle((int) (mSize.right / 2), (int) (mSize.bottom / 2), mWidthInside, mPaint); The problem with doing it this way, is the background is a static LTGRAY , which I hope to make Transparent. How would I go about leaving the center of the circle transparent?