Android 如何设置视图笔划宽度的动画

我有一个

ImageView

，背景设置为drawable.circle。圆的笔划宽度很宽。我想设置笔划宽度的动画，使其在指定的持续时间内从设定值缩小到1dp。如果这不能用drawable完成，我还有一个customView，路径是一个圆，paint.style设置为Stroke。我想将该动画应用于drawable.circle或customView

CustomCirleView：

public class CustomCircle extends View {

private Path path;
private Paint paint;
float customStrokeWidth = 80;


public float getCustomStrokeWidth() {
    return customStrokeWidth;
}

public void setCustomStrokeWidth(float customStrokeWidth) {
    this.customStrokeWidth = customStrokeWidth;
}


public CustomCircle(Context context, AttributeSet attrs) {
    super(context, attrs);
}

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    path = new Path();
    paint = new Paint();
    paint.setStyle(Paint.Style.STROKE);
    paint.setAntiAlias(true);
    paint.setColor(Color.parseColor("#FC6C2B"));
    paint.setStrokeWidth(customStrokeWidth);
    path.addCircle(getMeasuredWidth()/2, getMeasuredHeight()/2, (getMeasuredWidth()/2)-customStrokeWidth, Path.Direction.CW);

    canvas.drawPath(path, paint);
}

}

---

谢谢

我会这样做，然后用你的

onDraw

方法画一个圆圈。请不要在

onDraw

方法中进行所有绘制初始化，因为它总是需要一些时间，而

onDraw

方法应该尽可能少地进行初始化

private void init() {   
  animator = ObjectAnimator.ofFloat(this, "animationProgress", startVal, endVal);
  animator.setStartDelay(ANIMATION_START_DELAY);
  animator.setDuration(ANIMATION_DURATION);
  animator.setInterpolator(new FastOutSlowInInterpolator());

  path = new Path();
  paint = new Paint();
  paint.setStyle(Paint.Style.STROKE);
  paint.setAntiAlias(true);
  paint.setColor(Color.parseColor("#FC6C2B"));
  paint.setStrokeWidth(customStrokeWidth);
  path.addCircle(getMeasuredWidth()/2, getMeasuredHeight()/2, (getMeasuredWidth()/2)-customStrokeWidth, Path.Direction.CW);
}

/**
 * Is called by the {@link #animator} after an animation update
 */
protected void setAnimationProgress(float strokeWidth) {
    this.strokeWidth = strokeWidth;
    postInvalidateOnAnimation();
}

---

已设置动画的矢量绘图允许您设置笔划宽度的动画。如果需要对动画进行更精确的控制，则可以创建自定义可绘制视图并为其设置动画，它比自定义视图更解耦。