Android基础教程之-----访Iphone 拖动相片特效Gallery的简单应用.

Step 1:准备图片素材.

将icon2,icon3,icon4,icon5,icon6五张图片导入res/drawable里加上icon.png本身一共有6张图片.

Step 2:新建Android工程,命名为GalleryDemo.

Step 3:设计UI,修改main.xml代码如下:

<?xml version="1.0" encoding="utf-8"?> <LinearLayout     xmlns:android="http://schemas.android.com/apk/res/android"     android:background="@drawable/white"     android:orientation="vertical"     android:layout_width="fill_parent"     android:layout_height="fill_parent"     >     <TextView     android:id="@+id/myTextView01"     android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="@string/hello"     android:gravity="center_vertical|center_horizontal"     />     <Gallery     android:id="@+id/myGallery1"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:gravity="bottom"        />    </LinearLayout> 

Step 4:设计主程序类GalleryDemo.java代码如下: 

package com.android.test;  import com.android.test.R.drawable; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.Gallery; import android.widget.ImageView;  public class GalleryDemo extends Activity {  /** Called when the activity is first created. */  @Override  public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.main);       ((Gallery) findViewById(R.id.myGallery1)).setAdapter(new ImageAdapter(         this));  }   public class ImageAdapter extends BaseAdapter {     /* 类成员 myContext为Context父类 */     private Context myContext;      /* 使用res/drawable图片作为图片来源 */     private int[] myImageIds = { drawable.icon, drawable.icon2,         drawable.icon3, drawable.icon4, drawable.icon5, drawable.icon6};      /* 构造器只有一个参数，即要存储的Context */     public ImageAdapter(Context c) {      this.myContext = c;     }      /* 返回所有已定义的图片总数量 */     public int getCount() {      return this.myImageIds.length;     }      /* 利用getItem方法，取得目前容器中图像的数组ID */     public Object getItem(int position) {      return position;     }      public long getItemId(int position) {      return position;     }      /* 取得目前欲显示的图像View，传入数组ID值使之读取与成像 */     public View getView(int position, View convertView, ViewGroup parent) {      /* 创建一个ImageView对象 */      ImageView i = new ImageView(this.myContext);       i.setImageResource(this.myImageIds[position]);      i.setScaleType(ImageView.ScaleType.FIT_XY);       /* 设置这个ImageView对象的宽高，单位为dip */      i.setLayoutParams(new Gallery.LayoutParams(120, 120));      return i;     }      /* 依据距离中央的位移量 利用getScale返回views的大小(0.0f to 1.0f) */     public float getScale(boolean focused, int offset) {      /* Formula: 1 / (2 ^ offset) */      return Math.max(0, 1.0f / (float) Math.pow(2, Math.abs(offset)));     }  } } 

Step 5:run it,效果如下图:

 

注明:该代码基本参照Android SDK开发范例代码大全.今天晚上就懒一回呵呵...