如何在android中使用canvas画一个环？

Question

Can anybody suggest me how to draw a ring using canvas methods. I may draw to circles using canvas.drawCircle() but how should I feel a space between them?

Answer 1

1. You can draw a circle with a thick brush (use setStrokeWidth ).
2. You can draw two circles, one inside another. One filled with 'ring' color, and another (inner one) filled with screen 'background color'

Answer 2

In kotlin you can do:

• define your paint with stroke style whitin the init block

class CustomView(context: Context, attrs: AttributeSet) : View(context, attrs) {

private var ringPaint: Paint
  init {
        ringPaint = Paint()
        ringPaint.color = R.color.RED // Your color here
        ringPaint.style = Paint.Style.STROKE // This is the important line
        ringPaint.strokeWidth = 20f // Your stroke width in pixels
  }

}

• draw your circle in the onDraw method by using drawCircleFunction (centerX,centerY,radius,paint)

override fun draw(canvas: Canvas?) {
            super.draw(canvas)
            canvas?.drawCircle(width / 2.0f, height / 2.0f, (width - 10) / 2.0f, ringPaint)
        }