自定义View之旋转的弧形进度条

效果.gif

CircleArcView .java

import android.animation.ObjectAnimator;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.LinearInterpolator;

/**
 * by.benny
 * time 2018/10/14
 * descriptions: 旋转的弧形进度条
 */
public class CircleArcView extends View {
    Paint paint;
    private ObjectAnimator objectAnimator;
    private int STATE_STOP = 0;
    private int STATE_START = 1;
    private int STATE_PAUSE = 2;
    private int state;

    public CircleArcView(Context context) {
        super(context);
        init();
    }

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

    public CircleArcView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        paint = new Paint();
        paint.setStrokeWidth(8);
        paint.setStyle(Paint.Style.STROKE);
        paint.setColor(Color.RED);
        // 消除锯齿
        paint.setAntiAlias(true);
        startAnim();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        int w = getWidth();
        int h = getHeight();
        int radius = Math.min(w, h) / 2;

        //画圆
        //canvas.drawCircle(w/2,h/2,radius-50,paint);
        int arcLeng = 10;
        //画弧
        int sX=w * arcLeng / w;//弧形的起点X
        int sY=h * arcLeng / h;//弧形的起点Y
        int eX=w * (w-arcLeng) / w;//弧形的终点X
        int eY=h * (h-arcLeng) / h;//弧形的终点Y
        RectF oval = new RectF(sX, sY, eX, eY);
        canvas.drawArc(oval, 0, 160, false, paint);

        invalidate();

    }

    private void startAnim() {
        state = STATE_STOP;
        objectAnimator = ObjectAnimator.ofFloat(this, "rotation", 0f, 360f);
        //添加旋转动画，旋转中心默认为控件中点
        objectAnimator.setDuration(3000);
        //设置动画时间
        objectAnimator.setInterpolator(new LinearInterpolator());
        //动画时间线性渐变
        objectAnimator.setRepeatCount(ObjectAnimator.INFINITE);
        objectAnimator.setRepeatMode(ObjectAnimator.RESTART);
        play();
    }


    public void play() {
        if (state == STATE_STOP) {
            objectAnimator.start();
            //动画开始
            state = STATE_START;
        } else if (state == STATE_PAUSE) {
            objectAnimator.resume();
            //动画重新开始
            state = STATE_START;
        } else if (state == STATE_START) {
            objectAnimator.pause();
            // 动画暂停
            state = STATE_PAUSE;
        }
    }

    public void stop() {
        objectAnimator.end();
        // 动画结束
        state = STATE_STOP;
    }

}

circle_arc_layout.xml