Android入門筆記之Gallery

<1>簡介

      要實現這一效果，就必須有一個容器來存放Gallery所要顯示的圖片。這裏使用一個繼承自BaseAdapter的派生類來裝這些圖片。我們需要監聽其事件setOnItemClickListener,從而確定當前用戶選擇了那一張圖片並通過Toast顯示。

首先，我們需要將顯示的圖片的索引存放在一個int數組中。然後通過setImageResource方法來設置ImageView要顯示的圖片資源。最後將每張圖片的ImageView顯示在屏幕上。

<2>關鍵步驟

Gallery  wasdeprecated in API level 16.
This widget is nolonger supported. Other horizontally scrolling widgets include  HorizontalScrollView and  ViewPager from the support library.

<3>出現的問題

       無

<4>代碼及解釋

       效果圖：

GalleryActivity.java:

package com.ui.gallery;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.Toast;

import com.test.R;

public class GalleryActivity extends Activity{
	/**   
	 * @ProjectName:  [androidtest] 
	 * @Package:      [com.ui.grallery.GralleryActivity.java]  
	 * @ClassName:    [GralleryActivity]   
	 * @Description:    
	 * @Author:       [gmj]   
	 * @CreateDate:   [2013-8-28 下午4:16:05]   
	 * @Version:      [v1.0] 
	 */
	int [] imageIDs = {
		R.drawable.img1 , R.drawable.img2 ,  R.drawable.img3 ,  R.drawable.img4 ,
		 R.drawable.img5 ,  R.drawable.img6 , R.drawable.img7
	};
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_gallery);
		Gallery gl = (Gallery)this.findViewById(R.id.gallery1);
		BaseAdapter ba = new BaseAdapter()
		{
			@Override
			public int getCount() {
				// TODO Auto-generated method stub
				return imageIDs.length;
			}

			@Override
			public Object getItem(int arg0) {
				// TODO Auto-generated method stub
				return null;
			}

			@Override
			public long getItemId(int arg0) {
				// TODO Auto-generated method stub
				return 0;
			}

			@Override
			public View getView(int arg0, View arg1, ViewGroup arg2) {
				// TODO Auto-generated method stub
				ImageView iv = new ImageView(GalleryActivity.this);
				iv.setImageResource(imageIDs[arg0]);
				iv.setScaleType(ImageView.ScaleType.FIT_XY);
				iv.setLayoutParams(new Gallery.LayoutParams(640 , 360));
				return iv;
			}			
		};
		gl.setAdapter(ba);
		
		gl.setOnItemClickListener(
				new OnItemClickListener()
				{
					@Override
					public void onItemClick(AdapterView<?> arg0, View arg1,
							int arg2, long arg3) {
						// TODO Auto-generated method stub
						Gallery gl = (Gallery)findViewById(R.id.gallery1);
						gl.setSelection(arg2);
						Toast.makeText(GalleryActivity.this, "點擊了第" + arg2 + "張圖片", Toast.LENGTH_SHORT).show();
					}
				});
	}
}