Make Canvas easier to use in Kotlin

by androidexample

Kanvas

WORK IN PROGRESS

Make canvas easier to use in Kotlin blush

Use shapes & write less code to do more magic

val canvasAnimator = CanvasAnimator(this)

val background = RectShape {
        this.color = Color.parseColor("#6fbf73")
        this.cornerRadius = 16.dpToPx(context)
}.initWhenViewHasSize(this){ view ->
    left = 100f
    width = view.width / 2f
    top = 100f
    height = view.height / 3f
}


fun animate(){
    canvasAnimator
            .play(background.animate().right.to(this.width.toFloat()))
            .start()
}

override fun onDraw(canvas: Canvas) {
    super.onDraw(canvas)
    canvas.draw(background)
}

Examples




Available shapes

Shapes link
Rect
Circle
Text
Arc
Line
Triangle
Drawable
Path

Animation

Follow the example of SwitchView

Shape animations are executed by an instance of ShapeAnimator attached to your view

val canvasAnimator = CanvasAnimator(this)

All animated methods of shapes are wrapped into the method .animate()

For example, for a CircleShape, you can animate his position (centerX) using

myCircleShape.animate().centerX.to(15);

Then use your ShapeAnimator to execute this animation

shapeAnimator.play(myCircleShape.animate().centerX.to(15);)
    .setDuration(500)
    .start()

Added support methods to Canvas

drawArc(centerX, centerY, circleRadius, startAngle, sweepAngle, paint)

drawArc(center: PointF, circleRadius, startAngle, sweepAngle, paint)

drawArc(left, top, right, bottom, startAngle, sweepAngle, useCenter, paint)

drawOval(left, top, right, bottom, startAngle, sweepAngle, useCenter, paint)

drawLine(start: PointF, end: PointF, paint)

drawRoundRect(left, top, right, bottom, rx, ry, paint)

Added support methods to Path

addRoundRect(left, top, right, bottom, rx, ry, dir: Path.Direction)

addRoundRect(left, top, right, bottom, radiiArray, dir: Path.Direction)

arcTo(centerX, centerY, circleRadius, startAngle, sweepAngle, forceMoveTo)

arcTo(center: PointF, circleRadius, startAngle, sweepAngle, forceMoveTo)

arcTo(left, top, right, bottom, startAngle, sweepAngle, forceMoveTo)

GitHub