Android Developer Documentation

• onDraw()

Exercise

In this exercise you are going to draw a frame around the sketch.

1. In MyCanvasView, add a variable called frame that holds a Rect object.

private lateinit var frame: Rect

2. In onSizeChanged() add code to create the Rect that will be used for the frame, using the new dimensions and the inset.

// Calculate a rectangular frame around the picture.
val inset = 40
frame = Rect(inset, inset, width - inset, height - inset)

3. In onDraw(), after drawing the bitmap, draw a rectangle.

// Draw a frame around the canvas.
canvas.drawRect(frame, paint)

4. Run your app. Notice the frame.