Android自定义View实现圆环进度条

本文实例为大家分享了Android自定义View实现圆环进度条的具体代码，供大家参考，具体内容如下

效果展示

动画效果

View实现

1.底层圆环是灰色背景2.上层圆环是红色背景3.使用动画画一条弧线

View

/** * 圆环进度条 */public class RoundProgressBar extends View { //绘制矩形区域 private RectF rectF; //起始角度 private float startAngle; //扫过角度 private float sweepAngle; //画笔 private Paint paint; //默认控件大小 private int defoutSize; //默认线条宽度 private int defoutLine; private int strokeWidth; private PointF pointF = new PointF(); public RoundProgressBar(Context context) { super(context); initData(); } public RoundProgressBar(Context context, AttributeSet attrs) { super(context, attrs); initData(); } /** * 参数初始化 */ private void initData() { startAngle = 0; sweepAngle = 0; defoutSize = 400; defoutLine = 20; strokeWidth = 20; rectF = new RectF(); //抗锯齿画笔 paint = new Paint(Paint.ANTI_ALIAS_FLAG); paint.setColor(Color.GRAY); paint.setStrokeWidth(defoutLine); //笔帽样式 paint.setStrokeCap(Paint.Cap.ROUND); paint.setStyle(Paint.Style.STROKE); } /** * xml -----> 提供可绘制位置 * * @param widthMeasureSpec 宽 * @param heightMeasureSpec 高 */ @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); setMeasuredDimension(defoutSize, defoutSize); } /** * 当大小时改变回调 * * @param w * @param h * @param oldw * @param oldh */ @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); pointF.x = w >> 1; pointF.y = h >> 1; rectF.top = strokeWidth >> 1; rectF.bottom = h - (strokeWidth >> 1); rectF.left = strokeWidth >> 1; rectF.right = w - (strokeWidth >> 1); } /** * 绘制 * * @param canvas */ @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); //画布旋转 paint.setColor(Color.GRAY); canvas.rotate(135, pointF.x, pointF.y); //绘制圆环 canvas.drawArc(rectF, startAngle, 270, false, paint); paint.setColor(Color.RED); canvas.drawArc(rectF, startAngle, sweepAngle, false, paint); } public void setProgress(float index) { //防止数值越界 if (index > 1 || index < 0) { return; } ValueAnimator valueAnimator = ValueAnimator.ofFloat(0, index); valueAnimator.setDuration(3000); valueAnimator.setInterpolator(new DecelerateInterpolator()); valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { sweepAngle = (float) animation.getAnimatedValue() * 270; //重写绘制 invalidate(); } }); valueAnimator.start(); }}

最后在Activity中使用setProgress方法赋值进度条的进度来实现效果

progressView.setProgress(0.8f);

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持好吧啦网。