Android自定义view仿微信刷新旋转小风车

 package com.shipneg.demoysp.demo; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Matrix; import android.graphics.Paint; import android.os.CountDownTimer; import android.util.AttributeSet; import android.util.Log; import android.view.MotionEvent; import android.widget.ImageView; /** * Created by dell on 2017/4/7. */ public class RotationView extends ImageView { /** * 要转动的图片 **/ private Bitmap bitMap; /** * 风车每次转动的弧度 **/ private int rad = 0; /** * 风车移动的轨迹 **/ private int excursion = -100; /** * 图片的宽度：在这里提供的是正方形的图片，所以宽度和高度是一样的 **/ private int width = 0; /*** * 图片的高度：在这里提供的是正方形的图片，所以宽度和高度是一样的 **/ private int height = 0; /** * 定义一个画笔 **/ private Paint paint = new Paint(); public RotationView(Context context, AttributeSet attrs) { super(context, attrs); } public RotationView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); } public RotationView(Context context) { super(context); } /** * 获取图片的宽和高 */ public void initSize() { width = bitMap.getWidth(); height = bitMap.getHeight(); postInvalidate(); } public void setBitMap(Bitmap bitMap) { this.bitMap = bitMap; } //一图片的宽和高来设定自定义View的宽和高，由于是正方形宽和高是一样的 @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { // TODO Auto-generated method stub super.onMeasure(widthMeasureSpec, heightMeasureSpec); setMeasuredDimension(widthMeasureSpec, heightMeasureSpec); } CountDownTimer c = new CountDownTimer(5000, 10) { @Override public void onTick(long millisUntilFinished) { postInvalidate(); rad = rad + 7; } @Override public void onFinish() { downY = 0; excursion = -100; postInvalidate(); } }; /*** * 实现onDraw方法把风车图片绘制出来，同时绘制出来风车的旋转效果，通过Matrix来控制 */ @Override protected void onDraw(Canvas canvas) { Matrix matrix = new Matrix(); // 设置转轴位置 matrix.setTranslate((float) width / 2, (float) height / 2); //  rad -=15;//每次旋转的弧度增量为3当然，数字越大转动越快 // 开始转 matrix.preRotate(rad); // 开始平移 matrix.postTranslate(0, excursion); // 转轴还原 matrix.preTranslate(-(float) width / 2, -(float) height / 2); //绘制风车图片 canvas.drawBitmap(bitMap, matrix, paint); super.onDraw(canvas); } private int downY = 0; private int moveY = 0; private int abc = 0; @Override public boolean onTouchEvent(MotionEvent event) { int action = event.getAction(); switch (action) { case MotionEvent.ACTION_DOWN://随着手指的move而不断进行重绘，进而让风车转动起来 postInvalidate();//调用方法进行重绘 downY = (int) event.getY(); c.cancel(); break; case MotionEvent.ACTION_MOVE://随着手指的move而不断进行重绘，进而让风车转动起来 //调用方法进行重绘 int movey2 = moveY; rad = (int) -event.getY() * 6;//旋转的速度 moveY = (int) (event.getY() - downY);//手指移动的距离 int chz = moveY - movey2; if (chz > 10) { chz = chz / 10; } else if (chz <-10) { chz = chz / 10; } Log.e("TAG:" + excursion, "chz: " + chz + "//moveY:" + moveY + "//movey2:" + movey2); //100是向下滑动的最大距离 if (excursion >= 100) { abc = abc + chz; if (chz <0 && abc - chz < 0) { excursion=excursion + chz; } else>

 //调用的方法 RotationView rotation = (RotationView) view.findViewById(R.id.rotationView); BitmapDrawable drawable = (BitmapDrawable) getResources().getDrawable(R.drawable.fengche); rotation.setBitMap(drawable.getBitmap()); rotation.initSize();