本文實例為大家分享了Android自定義View實現圓環進度條的具體代碼，供大家參考，具體內容如下

效果展示

動畫效果

View實現

1.底層圓環是灰色背景2.上層圓環是紅色背景3.使用動畫畫一條弧線

View

/** * 圓環進度條 */public class RoundProgressBar extends View { //繪制矩形區域 private RectF rectF; //起始角度 private float startAngle; //掃過角度 private float sweepAngle; //畫筆 private Paint paint; //默認控件大小 private int defoutSize; //默認線條寬度 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(); } /** * 參數初始化 */ private void initData() { startAngle = 0; sweepAngle = 0; defoutSize = 400; defoutLine = 20; strokeWidth = 20; rectF = new RectF(); //抗鋸齒畫筆 paint = new Paint(Paint.ANTI_ALIAS_FLAG); paint.setColor(Color.GRAY); paint.setStrokeWidth(defoutLine); //筆帽樣式 paint.setStrokeCap(Paint.Cap.ROUND); paint.setStyle(Paint.Style.STROKE); } /** * xml -----> 提供可繪制位置 * * @param widthMeasureSpec 寬 * @param heightMeasureSpec 高 */ @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); setMeasuredDimension(defoutSize, defoutSize); } /** * 當大小時改變回調 * * @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); } /** * 繪制 * * @param canvas */ @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); //畫布旋轉 paint.setColor(Color.GRAY); canvas.rotate(135, pointF.x, pointF.y); //繪制圓環 canvas.drawArc(rectF, startAngle, 270, false, paint); paint.setColor(Color.RED); canvas.drawArc(rectF, startAngle, sweepAngle, false, paint); } public void setProgress(float index) { //防止數值越界 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; //重寫繪制 invalidate(); } }); valueAnimator.start(); }}

最后在Activity中使用setProgress方法賦值進度條的進度來實現效果

progressView.setProgress(0.8f);

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持好吧啦網。