一个Android自定义进度条

直接上代码

public class RoundLoadingBar extends View {
  private String TAG = RoundLoadingBar.class.getSimpleName();
  private Context mConText;
  private Paint mPaint;
  //大框的颜色
  private int mFramColor = Color.BLACK;
  //大圆的颜色
  private int mBigCircleColor = Color.BLACK;
  //小圆的颜色
  private int mSmallCircleColor = Color.BLACK;
  //大框的圆角度数
  private int mFrameAngle = 30;
  //大圆的半径
  private int mBigCircleRadius = 200;
  //小圆的半径
  private int mSmallCircleRadiue = 180;

  //大框透明度
  private int mFrameAlpha = 110;
  //小圆透明度
  private int mSmallCircleAlpha = 110;

  private int curValue = 0;

  public RoundLoadingBar(Context context, @Nullable AttributeSet attrs) {
      super(context, attrs);
      init(context, attrs);
  }


  private void init(Context context, AttributeSet attrs) {
      mConText = context;
      mPaint = new Paint();
      Log.e("zgj", " attrs " + attrs);
      if (attrs != null) {

          TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.RoundLoadingBar);

          mFrameAngle = ta.getDimensionPixelOffset(R.styleable.RoundLoadingBar_frame_angle, mFrameAngle);
          mFramColor = ta.getColor(R.styleable.RoundLoadingBar_frame_color, mFramColor);

          mBigCircleRadius = ta.getDimensionPixelOffset(R.styleable.RoundLoadingBar_bigcircle_radius, mBigCircleRadius);

          mSmallCircleColor = ta.getColor(R.styleable.RoundLoadingBar_smallcircle_color, mSmallCircleColor);
          mSmallCircleRadiue = ta.getDimensionPixelOffset(R.styleable.RoundLoadingBar_smallcircle_radius, mSmallCircleRadiue);

          float alpha = ta.getFloat(R.styleable.RoundLoadingBar_frame_alpha, 0.6f);
          mFrameAlpha = (int) (255 * alpha);
          alpha = ta.getFloat(R.styleable.RoundLoadingBar_smallcircle_alpha, 0.6f);
          mSmallCircleAlpha = (int) (255 * alpha);
      }
      invalidate();
  }

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

      //设置背景色
      canvas.drawColor(Color.TRANSPARENT);
      if (curValue >= 100) {
          return;
      }
      //画背景半透明的框
      int canvasWidth = canvas.getWidth();
      int canvasHeight = canvas.getHeight();
      int layerId = canvas.saveLayer(0, 0, canvasWidth, canvasHeight, null, Canvas.ALL_SAVE_FLAG);
      mPaint.setColor(curValue == 100 ? Color.TRANSPARENT : mBigCircleColor);
      mPaint.setAlpha(mFrameAlpha);
      RectF rectF = new RectF(0, 0, getWidth(), getHeight());
      canvas.drawRoundRect(rectF, mFrameAngle, mFrameAngle, mPaint);
      mPaint.reset();

      //画中心透明的圆
      //使用CLEAR作为PorterDuffXfermode绘制
      mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
//        mPaint.setColor(0xFF66AAFF);
      mPaint.setColor(mBigCircleColor);
      canvas.drawCircle(getWidth() / 2, getHeight() / 2, mBigCircleRadius, mPaint);
      //最后将画笔去除Xfermode
      mPaint.setXfermode(null);
      canvas.restoreToCount(layerId);

      //根据度数画圆弧
      mPaint.setColor(mSmallCircleColor);
      mPaint.setAlpha(mSmallCircleAlpha);
      @SuppressLint("DrawAllocation")
      RectF rect = new RectF((getWidth() / 2) - mSmallCircleRadiue,
              (getHeight() / 2) - mSmallCircleRadiue,
              (getWidth() / 2) + mSmallCircleRadiue,
              (getHeight() / 2) + mSmallCircleRadiue);
      float angle = (360f / 100f) * (float) curValue;
      Log.d(TAG, " angle " + angle);
      canvas.drawArc(rect, //弧线所使用的矩形区域大小
              -90 + angle,  //开始角度
              360 - angle, //扫过的角度
              true, //是否使用中心
              mPaint);


  }

  public void setValue(int value) {
      curValue = value;
      invalidate();
  }
}

attrs

 <declare-styleable name="RoundLoadingBar">
        <attr name="bigcircle_radius" format="dimension" />
        <attr name="smallcircle_radius" format="dimension" />
        <attr name="frame_angle" format="dimension" />
        <attr name="frame_alpha" format="float" />
        <attr name="smallcircle_color" format="color" />
        <attr name="smallcircle_alpha" format="float" />
        <attr name="frame_color" format="color" />
    </declare-styleable>