Android开发之欢迎界面标准

 1 import java.util.ArrayList;
 2 
 3 import android.app.Activity;
 4 import android.content.SharedPreferences;
 5 import android.os.Bundle;
 6 import android.support.v4.view.PagerAdapter;
 7 import android.support.v4.view.ViewPager;
 8 import android.view.LayoutInflater;
 9 import android.view.View;
10 import android.view.ViewGroup;
11 import android.view.ViewGroup.LayoutParams;
12 
13 //安卓应用欢迎界面标准
14 public class MainActivity extends Activity {
15     private ViewPager viewPager;
16     private ViewPagerAdapter pagerAdapter = new ViewPagerAdapter();
17     // 欢迎界面显示的视图ID
18     private int[] viewsId = { R.layout.wel1, R.layout.wel2, R.layout.wel3 };
19     // 缓冲界面显示的视图ID
20     private int cacheId = R.layout.wel2;
21 
22     @Override
23     protected void onCreate(Bundle savedInstanceState) {
24         super.onCreate(savedInstanceState);
25         SharedPreferences shared = this.getSharedPreferences("app_global",
26                 MODE_WORLD_WRITEABLE);
27         viewPager = new ViewPager(this);
28         viewPager.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,
29                 LayoutParams.MATCH_PARENT));
30         if (!shared.contains("used")) {
31             pagerAdapter.setViewsId(viewsId);
32             shared.edit().putBoolean("used", true).commit();
33         } else {
34             pagerAdapter.setViewsId(cacheId);
35         }
36         viewPager.setAdapter(pagerAdapter);
37 
38         // 获取最后一个视图，以便绑定事件
39         View v = pagerAdapter.getLastView();
40 
41         setContentView(viewPager);
42     }
43 
44     // 在其中写入当显示缓冲图片时执行的操作
45     protected void onShowCachePicture() {
46 
47     }
48 
49     private class ViewPagerAdapter extends PagerAdapter {
50         private ArrayList<View> viewList = new ArrayList<View>();
51 
52         @Override
53         public void destroyItem(ViewGroup container, int position, Object object) {
54             container.removeView(viewList.get(position));
55         }
56 
57         @Override
58         public Object instantiateItem(ViewGroup container, int position) {
59             container.addView(viewList.get(position));
60             return viewList.get(position);
61         }
62 
63         @Override
64         public int getCount() {
65             return viewList.size();
66         }
67 
68         @Override
69         public boolean isViewFromObject(View arg0, Object arg1) {
70             return arg0 == arg1;
71         }
72 
73         public void setViewsId(int... ids) {
74             LayoutInflater inflater = getLayoutInflater();
75             for (int id : ids) {
76                 View v = inflater.inflate(id, null);
77                 viewList.add(v);
78             }
79         }
80 
81         public View getLastView() {
82             return viewList.get(viewList.size() - 1);
83         }
84     }
85 
86 }