Android

1.

public Yuan(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    //圆弧
    paint = new Paint();
    paint.setAntiAlias(true);
    paint.setStyle(Paint.Style.STROKE);
    paint.setStrokeWidth(16f);
    paint.setColor(Color.BLUE);
    paint.setStrokeCap(Paint.Cap.ROUND);
    //进度圆弧
    paint1 = new Paint();
    paint1.setAntiAlias(true);
    paint1.setStyle(Paint.Style.STROKE);
    paint1.setStrokeWidth(16f);
    paint1.setColor(Color.RED);
    paint1.setStrokeCap(Paint.Cap.ROUND);
    //文字
    paint2 = new Paint();
    paint2.setAntiAlias(true);
    paint2.setStyle(Paint.Style.FILL);
    paint2.setStrokeWidth(10f);
    paint2.setTextSize(20f);
    paint2.setColor(Color.BLACK);
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    int width = getMeasuredWidth();
    int height = getMeasuredHeight();
    rectF = new RectF(0, 0, width, height);
    setMeasuredDimension(300, 300);
}

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    //画圆弧
    canvas.drawArc(rectF, 0, 360, false, paint);
    //进度
    float sweepAngle = 360 * mCurrent / 100;
    canvas.drawArc(rectF, 360, sweepAngle, false, paint1);
    //文字进度
    String text = mCurrent + "%";
    //文字的宽度
    float textWidth = paint2.measureText(text, 0, text.length());
    float dx = getWidth() / 2 - textWidth / 2;
    Paint.FontMetricsInt fontMetricsInt = paint2.getFontMetricsInt();
    float dy = (fontMetricsInt.bottom - fontMetricsInt.top);
    float baseLine = getHeight() / 2 + dy;
    canvas.drawText(text, dx, baseLine, paint2);
    if (onLoading != null && mCurrent == 100) {
        onLoading.complete();
    }
}

private onLoading onLoading;

public void setLoading(int mCurrent) {
    this.mCurrent = mCurrent;
    invalidate();
}
public void setOnLoading(onLoading onLoading) {
    this.onLoading = onLoading;
}

public interface onLoading {
    void complete();
}

2.

yuan = findViewById(R.id.yuan);
ValueAnimator animator = ValueAnimator.ofFloat(0, 100);
animator.setDuration(6000);
animator.setInterpolator(new LinearInterpolator());
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
    @Override
    public void onAnimationUpdate(ValueAnimator animation) {
        float current = (float) animation.getAnimatedValue();
        yuan.setLoading((int) current); }
});
animator.start();
yuan.setOnLoading(new Yuan.onLoading() {
    @Override
    public void complete() {
        startActivity(new Intent(TwoActivity.this, MainActivity.class));
    }
});