android开发之gallery 实现滚动一张且短距离滑动实现滚动

首先gallery的特点就不用多说了吧，惯性滚动、半屏翻页，但是很多时候我们不需要它的这些特性。我今天就介绍一下 去掉惯性滚动 以及 短距离翻页的实现：
代码先晒出来：
main.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<com.mh.DetialGallery  android:id="@+id/gallery" android:layout_width="fill_parent"  
        android:layout_height="fill_parent"  />  
</LinearLayout>

DetialGallery 是自己继承的类。

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;

public class main extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN ,  
     WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.main);
        Gallery gallery = (Gallery) findViewById(R.id.gallery);   
        gallery.setAdapter(new ImageAdapter(this));;  

    }
    
    private int[] resIds = new int[]   
         { R.drawable.a1, R.drawable.a2, R.drawable.a3,           
           R.drawable.a4, R.drawable.a5, R.drawable.a6,         
           R.drawable.a7, R.drawable.a8, R.drawable.a9    
         };  
    
    
   

 public class ImageAdapter extends BaseAdapter   
    {   
        int mGalleryItemBackground;   
        private Context mContext;   
      
        public ImageAdapter(Context context)   
        {   
            mContext = context;                     
        }  

        public int getCount()   
        {   
            return resIds.length;   
        }   
        public Object getItem(int position)   
        {   
            return position;   
        }   
      
        public long getItemId(int position)   
        {   
            return position;   
        }   
        
        public View getView(int position, View convertView, ViewGroup parent)   
        {   
            ImageView imageView = new ImageView(mContext);   
            imageView.setImageResource(resIds[position]);
            imageView.setScaleType(ImageView.ScaleType.FIT_XY);   
            imageView.setLayoutParams(new Gallery.LayoutParams(480, 800));   //分辨率自己定
            return imageView;   
        }   
    } 

}

import android.content.Context;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.widget.Gallery;

public class DetialGallery extends Gallery {

    public DetialGallery(Context context ,AttributeSet attrSet) {
     super(context,attrSet);
     // TODO Auto-generated constructor stub
    }

 private boolean isScrollingLeft(MotionEvent e1, MotionEvent e2)
   {   
    return e2.getX() > e1.getX(); 
   }
 @Override
 public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
   float velocityY) {
  // TODO Auto-generated method stub
//  return super.onFling(e1, e2, 0, velocityY);//方法一：只去除翻页惯性
//  return false;//方法二：只去除翻页惯性  注：没有被注释掉的代码实现了开始说的2种效果。
  int kEvent;  
  if(isScrollingLeft(e1, e2)){ 
   //Check if scrolling left     
   kEvent = KeyEvent.KEYCODE_DPAD_LEFT;  
   }  else{ 
    //Otherwise scrolling right    
    kEvent = KeyEvent.KEYCODE_DPAD_RIGHT;   
    }  
  onKeyDown(kEvent, null);  
  return true;  
  }
 }

让Android自带的Gallery实现多点缩放，拖动和边界回弹效果，效果流畅
http://www.havenliu.com/android/668.html