Android 画闹钟

1.今天就来模仿一下这个小闹钟的

2.思路：

• 先画闹钟的圆盘 ，在通过Path来画指针
• 两个耳朵其实就是用两个圆被一个大圆截取后留下的，并旋转一定度数后生成

3.直接上代码：

　　

 public class AlarmClockView extends View {

     private static final PorterDuff.Mode MODE = PorterDuff.Mode.DST_OUT;
     /**
      * 屏幕适应性参数
      */
     private static final float BIG_RADIU = 1 / 6F;
     private static final float SMALL_RADIU = 1 / 12F;
     private static final float CLOCKWISE_LENGTH = 1 / 10F;
     private static final float MINUTE_LENGTH = 1 / 12f;
     private static final float MASK_RADIU = 1 / 4F;

     // 大圆盘圈
     private Paint mPaint;
     // 指针Paint
     private Paint zhenPaint;
     // 小圆Paint
     private Paint smallCirclePaint;
     private Path path;
     private int screenW, screenH;
     /**
      * 大圆半径
      *
      * @param context
      */
     private float radius_big, small_radiu, clockwise_length, minute_length,
             mask_radiu;

     public AlarmClockView(Context context) {
         super(context);
     }

     public AlarmClockView(Context context, AttributeSet attrs) {
         super(context, attrs);

         mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         mPaint.setStyle(Paint.Style.STROKE);
         mPaint.setColor(Color.WHITE);
         mPaint.setStrokeWidth(40);

         zhenPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         zhenPaint.setStyle(Paint.Style.STROKE);
         zhenPaint.setColor(Color.WHITE);
         zhenPaint.setStrokeWidth(20);

         smallCirclePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         smallCirclePaint.setStyle(Paint.Style.FILL);
         smallCirclePaint.setColor(Color.WHITE);

         screenW = new MeasureUtil().getWindowWidth(context);
         screenH = new MeasureUtil().getWindowHeigh(context);

         int size = Math.min(screenW, screenH);
         radius_big = size * BIG_RADIU;
         small_radiu = size * SMALL_RADIU;
         clockwise_length = size * CLOCKWISE_LENGTH;
         minute_length = size * MINUTE_LENGTH;
         mask_radiu = size * MASK_RADIU;
         // 设置指针
         path = new Path();
         path.moveTo(screenW / 2, screenH / 2 + 10);
         path.lineTo(screenW / 2, screenH / 2 - clockwise_length + 10);
         path.moveTo(screenW / 2 - 10, screenH / 2 + 10);
         path.lineTo(screenW / 2 + minute_length, screenH / 2 + 10);
     }

     @Override
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);
         canvas.drawColor(Color.argb(255, 255, 128, 103));

         canvas.drawCircle(screenW / 2, screenH / 2, radius_big, mPaint);
         canvas.drawPath(path, zhenPaint);

         // 画耳朵圆
         drawEarCircle(canvas, 30);
         drawEarCircle(canvas, -30);

     }

     private void drawEarCircle(Canvas canvas, int degree) {
         int layerID = canvas.saveLayer(0, 0, screenW, screenH, null,
                 Canvas.ALL_SAVE_FLAG);
         canvas.rotate(degree, screenW / 2, screenH / 2);
         canvas.drawCircle(screenW / 2, screenH / 2 - radius_big - small_radiu,
                 small_radiu, smallCirclePaint);
         // 用一个大圆去遮罩
         PorterDuffXfermode xfermode = new PorterDuffXfermode(MODE);
         smallCirclePaint.setXfermode(xfermode);
         canvas.drawCircle(screenW / 2, screenH / 2, mask_radiu,
                 smallCirclePaint);
         smallCirclePaint.setXfermode(null);
         canvas.restoreToCount(layerID);
     }

 }

4.运行后的效果是：