Android实现图片随手指旋转功能

package com.example.roatedemo;  import java.util.Calendar; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Matrix; import android.graphics.Paint; import android.util.Log; import android.view.MotionEvent; import android.view.View;  public class RotateView extends View {   private Paint mPaint = new Paint();   private Bitmap bitmaplittele;//中间不动的图片   private Bitmap bitmapBig;//随手指转动的图片   private Bitmap bitmapOut;//外围不动的图片   // 圆心坐标   private float mPointX = 0, mPointY = 0;    private int flag = 0;   // 半径   private int mRadius = 0;   // 旋转角度   private int mAngle = 0;   private int beginAngle = 0, currentAngle = 0;   private String TAG = "NewView";   int bitMap[] = { R.drawable.circle0, R.drawable.circle1, R.drawable.circle2 };   int imageIndex = 0;   boolean isUp = false,isTouch=false;   Context mContext;   RotateViewListener listener;   long beginTime,endTime;   Calendar now;    public RotateView(Context context, int px, int py, int radius,RotateViewListener listener) {     super(context);     mContext = context;     this.listener = listener;     mPointX = px;     mPointY = py;     mRadius = radius;     bitmaplittele = BitmapFactory.decodeResource(getResources(),         R.drawable.a1_pointer).copy(Bitmap.Config.ARGB_8888, true);     bitmapBig = BitmapFactory.decodeResource(getResources(), bitMap[0])         .copy(Bitmap.Config.ARGB_8888, true);     bitmapOut = BitmapFactory.decodeResource(getResources(),         R.drawable.bigcir).copy(Bitmap.Config.ARGB_8888, true);     setBackgroundResource(R.drawable.back);     Log.e(TAG, "RotateViewBegin");      }    @Override   public boolean dispatchTouchEvent(MotionEvent e) {     switch (e.getAction() & MotionEvent.ACTION_MASK) {     case MotionEvent.ACTION_DOWN:       now = Calendar.getInstance();       beginTime = now.getTimeInMillis();       beginAngle = computeCurrentAngle(e.getX(), e.getY());       isUp = false;       //如果点击触摸范围在圈外，则不处理       if (getDistance(e.getX(), e.getY())>bitmapOut.getWidth()/2) {         isTouch=false;       }else {         isTouch=true;       }       return true;     case MotionEvent.ACTION_MOVE:       if (!isTouch) {         return true;       }       currentAngle = computeCurrentAngle(e.getX(), e.getY());       invalidate();       return true;     case MotionEvent.ACTION_UP:       isUp = true;       if (!isTouch) {         return true;       }       now = Calendar.getInstance();       endTime = now.getTimeInMillis();       if (SetClick(e.getX(), e.getY())) {         return true;       }             if (mAngle > 0) {         int count = mAngle / 120 + (mAngle % 120 > 60 ? 1 : 0);         imageIndex = (imageIndex + count) % 3;       } else if (mAngle < 0) {         mAngle = -mAngle;         int count = mAngle / 120 + (mAngle % 120 > 60 ? 1 : 0);         imageIndex = (imageIndex + 3 - count) % 3;       }       bitmapBig = BitmapFactory.decodeResource(getResources(),           bitMap[imageIndex]).copy(Bitmap.Config.ARGB_8888, true);       bitmapBig = adjustPhotoRotation(bitmapBig, imageIndex * 120);       invalidate();       if (mAngle >= 60) {         listener.onModChange(imageIndex);       }             return true;     }      return false;   }    @Override   public void onDraw(Canvas canvas) {     // Log.i(TAG, "onDraw");     // 大圆     drawInCenter(canvas, bitmapOut, mPointX, mPointY, TAG);     // 外圈     if (isUp) {       mAngle = 0;     } else {       mAngle = currentAngle - beginAngle;     }      Bitmap tempBig = adjustPhotoRotation(bitmapBig, mAngle);     // Log.i(TAG, "mAngle:"+mAngle);     drawInCenter(canvas, tempBig, mPointX, mPointY + 10, TAG);     // 小圆(中间的圆心)     drawInCenter(canvas, bitmaplittele, mPointX, mPointY - 10, TAG);   }    Bitmap adjustPhotoRotation(Bitmap bm, final int orientationDegree) {     if (orientationDegree == 0) {       return bm;     }     Matrix m = new Matrix();     m.setRotate(orientationDegree, (float) bm.getWidth() / 2,         (float) bm.getHeight() / 2);      try {       Bitmap bm1 = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(),           bm.getHeight(), m, true);        return bm1;      } catch (OutOfMemoryError ex) {     }      return null;    }    private void drawInCenter(Canvas canvas, Bitmap bitmap, float left,       float top, String text) {     canvas.drawBitmap(bitmap, left - bitmap.getWidth() / 2,         top - bitmap.getHeight() / 2, null);   }    // 子控件位置改变重新计算角度   private int computeCurrentAngle(float x, float y) {     // 根据圆心坐标计算角度     float distance = (float) Math         .sqrt(((x - mPointX) * (x - mPointX) + (y - mPointY)             * (y - mPointY)));     int degree = (int) (Math.acos((x - mPointX) / distance) * 180 / Math.PI);     if (y < mPointY) {       degree = -degree;     }     if (degree < 0) {       degree += 360;     }      // Log.i("RoundSpinView", "x:" + x + ",y:" + y + ",degree:" + degree);     return degree;   }    // 获取距离圆心的距离   private float getDistance(float x, float y) {     // 根据圆心坐标计算角度     float distance = (float) Math         .sqrt(((x - mPointX) * (x - mPointX) + (y - mPointY)             * (y - mPointY)));     return distance;   }    //点击   private boolean SetClick(float x, float y) {     float distance = getDistance(x, y);     if (mAngle>10||mAngle<-10) {       return false;     }else if(endTime-beginTime>1000){       return false;     }     if (distance < bitmapBig.getWidth() / 2) {       int mod = 0;              if (beginAngle < 90 || 330 < beginAngle) {         mod = (imageIndex+3-1)%3;                     }       else if (90 < beginAngle && 210 > beginAngle) {         mod = (imageIndex+3-2)%3;               }       else{         mod = imageIndex;               }       //回调到主界面进行处理。       listener.onModClick(mod);     }     return true;   }      public interface RotateViewListener {         void onModClick(int mode);     void onModChange(int mode);   } }

package com.example.roatedemo;  import com.example.roatedemo.RotateView.RotateViewListener;  import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.util.DisplayMetrics; import android.util.Log; import android.widget.Toast;  public class MainActivity extends Activity implements RotateViewListener{    RotateView rotateView;   String TAG="MainActivity";   Context mContext;   @Override   protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     mContext = this;     int height,width;     DisplayMetrics displayMetrics = new DisplayMetrics();      getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);     height = displayMetrics.heightPixels;     width = displayMetrics.widthPixels;     Log.i(TAG, "height:"+height);     Log.i(TAG, "width:"+width);     rotateView = new RotateView(getApplicationContext(), width/2, height/3, 150,this);      setContentView(rotateView);   }   @Override   public void onModClick(int mode) {     String[] clickStrings = new String[] { "1被点击", "2被点击","3被点击" };     Toast.makeText(mContext, clickStrings[mode], 0).show();        }   @Override   public void onModChange(int mode) {     String[] clickStrings = new String[] { "切换到1", "切换到2","切换到3" };     Toast.makeText(mContext, clickStrings[mode], 0).show();    }   }