Android 图片轮番 继承ViewGroup实现 可以直接使用

代码有注释应该都能看的懂

上代码：

import java.util.ArrayList;import android.content.Context;import android.graphics.Bitmap;import android.os.Handler;import android.os.Message;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.VelocityTracker;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;import android.widget.Scroller;public class ImageViewGroup extends ViewGroup {   private InageViewGardenSwitch gardenSwitch = null;//用于返回当前界面的编号（对外编号）   private Context mContext;   private Scroller mScroller = null;//滑动动画   private int cens = 0;//当前显示界面的编号（初始值为0   0是中间  比如有五张图片那么0代表第三张图片，排序是-2，-1，0，1，2）   /*总共view的数量   总共图片数量为当前图片加2，因为这图片循环是伪无限循环， 需要添两张图片作为过渡，   这两张图片添加规则为：比如有5张图片         1，2，3，4，5      进来的图片的编号       5，1，2，3，4，5，1   添加两张图片之后的队列    -3，-2，-1，0，1，2，3   重新编号    */   private int max = 0;   //最左边的view编号 （添加两张图片后的最左边位置）   private int leftJump = 0;   //同上方向是右边   private int rightJump = 0;   //如果当前显示为最左边的图片则跳转的目标图片编号   private int targetRight = 0;   private int targetLeft = 0;//同上   private boolean isTouch = false;//判断手指是否在控件上（是则不执行自动跳转）   private static final int TOUCH_STATE_REST = 0;   private static final int TOUCH_STATE_SCROLLING = 1;   private int mTouchState = TOUCH_STATE_REST;   private boolean isThread = true;//自动跳转线程开关   //--------------------------   public static int  SNAP_VELOCITY = 600 ;   private int mTouchSlop = 0 ;   private float mLastionMotionX = 0 ;   private VelocityTracker mVelocityTracker = null ;   private int sizeWidth = 0;//控件的宽度   private int sizeHeight= 0;//控件的高度   public ImageViewGroup(Context context, AttributeSet attrs) {      super(context, attrs);      // TODO Auto-generated constructor stub      this.mContext = context;      mScroller = new Scroller(context);   }   /*    * 滑动到下一张图片    */    public void startMove(){         if(cens == rightJump){            cens = leftJump + 1;         }         cens++ ;         mScroller.startScroll((cens-1)*getWidth(), 0,getWidth(), 0,2000);         invalidate();         theCurrentlyDisplayed();      }   /*    * 开启线程定时滑动到下一张图片    */    public void timingMove(){       Handler handler = new Handler(){         /* (non-Javadoc)          * @see android.os.Handler#handleMessage(android.os.Message)          */         @Override         public void handleMessage(Message msg) {            // TODO Auto-generated method stub            super.handleMessage(msg);            if(!isTouch){//判断当时是不是在执行手势               if(mScroller != null){//判断当前是不是正在执行动画                  startMove();               }            }         }       };       new Thread(new timing(handler)).start();    }   //线程定时   class timing implements Runnable{       private Handler handler;       public timing(Handler handler) {         // TODO Auto-generated constructor stub          this.handler = handler;      }      @Override      public void run() {         while (isThread) {               try {               Thread.sleep(4000);                  handler.sendMessage(new Message());            } catch (InterruptedException e) {               // TODO Auto-generated catch block               e.printStackTrace();            }         }      }    }   /*    * 初始化    */   @Override   public void computeScroll() {         // TODO Auto-generated method stub      if (mScroller.computeScrollOffset()) {            scrollTo(mScroller.getCurrX(), mScroller.getCurrY());            postInvalidate();      }else{      }   }   /*    * 设置图片并在首尾添加过渡图片    */   public void setListImageView(ArrayList<Bitmap> list,InageViewGardenSwitch gardenSwitch){      this.gardenSwitch = gardenSwitch;      if(list != null && list.size() != 0){         ImageView top = new ImageView(mContext);         top.setImageBitmap(list.get(list.size()-1));         addView(top);         for (int i = 0; i < list.size(); i++) {            ImageView img = new ImageView(mContext);            img.setImageBitmap(list.get(i));            addView(img);         }         ImageView buttom = new ImageView(mContext);         buttom.setImageBitmap(list.get(0));         addView(buttom);               }   }      /*    * 手势监听    */   @Override    public boolean onTouchEvent(MotionEvent event) {       // TODO Auto-generated method stub       if(mVelocityTracker == null){          mVelocityTracker = VelocityTracker.obtain();       }       mVelocityTracker.addMovement(event);       super.onTouchEvent(event);       float x = event.getX();       float y = event.getY();       switch (event.getAction()) {      case MotionEvent.ACTION_DOWN:         isTouch = true;//设置手势正在监听中         if(mScroller != null){//判断当前是否在执行动画            mScroller.abortAnimation();//停止动画         }         if(cens == leftJump){//判断当前显示是否是最左边的图片            scrollBy(targetRight, 0);//跳转到最右侧-1的图片            cens = rightJump - 1;         }         if(cens == rightJump){//同上            scrollBy(targetLeft, 0);            cens = leftJump + 1;         }         mLastionMotionX = x;         break;      case MotionEvent.ACTION_MOVE:          isTouch = true;         int dataX = (int)(mLastionMotionX - x);         scrollBy(dataX, 0);         mLastionMotionX = x;         break;      case MotionEvent.ACTION_UP:         isTouch = false;         final VelocityTracker velocityTracker = mVelocityTracker;         velocityTracker.computeCurrentVelocity(1000);         int velocityX = (int) velocityTracker.getXVelocity();         System.out.println(velocityX+"aa");         if(velocityX > SNAP_VELOCITY){            snapToScreen(cens - 1);         }else if(velocityX < -SNAP_VELOCITY){            snapToScreen(cens + 1);         }else{            snapToDestination();         }         if (mVelocityTracker != null) {            mVelocityTracker.recycle();            mVelocityTracker = null;         }         mTouchState = TOUCH_STATE_REST ;      case MotionEvent.ACTION_CANCEL:         mTouchState = TOUCH_STATE_REST ;         break;               default:         break;      }             return true;    }         public boolean commOnTouchEvent(MotionEvent ev) {         // TODO Auto-generated method stub         final int action = ev.getAction();         if ((action == MotionEvent.ACTION_MOVE) && (mTouchState != TOUCH_STATE_REST)) {            return true;         }         final float x = ev.getX();         final float y = ev.getY();         switch (action) {         case MotionEvent.ACTION_MOVE:            final int xDiff = (int) Math.abs(mLastionMotionX - x);            if (xDiff > mTouchSlop) {               mTouchState = TOUCH_STATE_SCROLLING;            }            break;         case MotionEvent.ACTION_DOWN:            mLastionMotionX = x;            mTouchState = mScroller.isFinished() ? TOUCH_STATE_REST : TOUCH_STATE_SCROLLING;            break;         case MotionEvent.ACTION_CANCEL:         case MotionEvent.ACTION_UP:            mTouchState = TOUCH_STATE_REST;            break;         }         return mTouchState != TOUCH_STATE_REST;      }   private void snapToDestination(){      int destScreen = (getScrollX() + getWidth() / 2 ) / getWidth() ;      snapToScreen(destScreen);   }   private void snapToScreen(int whichScreen){           cens = whichScreen;       int dx = (cens)*getWidth() - getScrollX();       int time = Math.abs(dx) * 2;       mScroller.startScroll(getScrollX(), 0, dx, 0,time);       invalidate();       System.out.println(cens);       theCurrentlyDisplayed();           }          @Override   protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {      // TODO Auto-generated method stub      super.onMeasure(widthMeasureSpec, heightMeasureSpec);       sizeWidth = MeasureSpec.getSize(widthMeasureSpec);         sizeHeight = MeasureSpec.getSize(heightMeasureSpec);         setMeasuredDimension(sizeWidth, sizeHeight);   }        @Override   protected void onLayout(boolean arg0, int arg1, int arg2, int arg3, int arg4) {      // TODO Auto-generated method stub      int count = getChildCount();      int ce = 0;      System.out.println(count);      if(count <= 2)         return;      int childL = 0;      int childR = sizeWidth;      int childLs = 0;      int childRs = sizeWidth;      ce = count/2;      View cen = getChildAt(ce);      cen.layout(childL, 0, childR, sizeHeight);      for (int i = ce+1; i < count; i++) {         View view = getChildAt(i);         childL+=sizeWidth;         childR+=sizeWidth;         view.layout(childL, 0, childR, sizeHeight);      }      for (int i = ce-1; i >= 0; i--) {         View view = getChildAt(i);         childLs-=sizeWidth;         childRs-=sizeWidth;         view.layout(childLs, 0, childRs, sizeHeight);      }            max = count;      leftJump = -count/2;      if(count%2 == 0){         rightJump = count / 2 - 1;      }else{         rightJump = count / 2;      }      targetRight = (max - 2)*sizeWidth;      targetLeft = -(max - 2)*sizeWidth;            if(isTiming){         timingMove();      }      isTiming = false;   }   private boolean isTiming = true;   @Override   protected void onDetachedFromWindow() {      // TODO Auto-generated method stub      super.onDetachedFromWindow();      isThread = false;   }      public void theCurrentlyDisplayed(){      System.out.println(cens +"dangqiande "+leftJump);      if(cens == leftJump)         gardenSwitch.onSwitch((max-2)-1);      else      if(cens == rightJump)         gardenSwitch.onSwitch(0);      else         gardenSwitch.onSwitch(cens - (leftJump+1));               }   //手势监听获取   @Override   public boolean dispatchTouchEvent(MotionEvent ev) {      getParent().requestDisallowInterceptTouchEvent(true);      super.dispatchTouchEvent(ev);      commOnTouchEvent(ev);      return true;   }}

//接口类  用于返回当前显示的是第几张图片。 

public interface InageViewGardenSwitch {   public void onSwitch(int i);}

使用方法：

xml:

<main.diyview.ImageViewGroup    android:id="@+id/homePageImageGroup"    android:layout_width="match_parent"    android:layout_height="match_parent"    ></main.diyview.ImageViewGroup>
activity:

public class main extends Activity implements InageViewGardenSwitch{
   private ImageViewGroup imageViewGroup;
   protected void onCreate(Bundle savedInstanceState) {   // TODO Auto-generated method stub  super.onCreate(savedInstanceState);
    setContentView(R.layout.home_page);    imageViewGroup = (ImageViewGroup)findViewById(R.id.homePageImageGroup);
    ArrayList<Bitmap> imagelist = new ArrayList<Bitmap>();
    Bitmap bitmap1 = BitmapFactory.decodeResource(this.getResources(), R.drawable.banner1);    Bitmap bitmap2 = BitmapFactory.decodeResource(this.getResources(), R.drawable.banner2);    Bitmap bitmap3 = BitmapFactory.decodeResource(this.getResources(), R.drawable.banner3);    imagelist.add(bitmap1);    imagelist.add(bitmap2);    imagelist.add(bitmap3);    imageViewGroup.setListImageView(imagelist, this);  
}
   @Override   public void onSwitch(int i) {
//返回当前显示第几张图片  可以用于小圆点切换
   } 

}

代码可能有一些错误 或者可以优化的地方请指出