• ListView小用法


    列表标题:照片名,编号,照片得分

    根据ArrayList<Photo> photos 依次添加列表项。关键点设置为adapter的六个参数,并且用getData()方法得到 List<HashMap<Object, Object>>类型的对象

     1 package cqu.wm;
    2
    3 import java.io.File;
    4 import java.util.ArrayList;
    5 import java.util.HashMap;
    6 import java.util.List;
    7 import tool.Photo;
    8 import tool.PhotoService;
    9 import android.app.ListActivity;
    10 import android.os.Bundle;
    11 import android.os.Environment;
    12 import android.widget.SimpleAdapter;
    13
    14 public class myListActivity extends ListActivity {
    15
    16 /** Called when the activity is first created. */
    17 public static final String TAG = "dbtest";
    18 PhotoService photoservice = null;
    19 ArrayList<Photo> photos = new ArrayList<Photo>();
    20
    21 @Override
    22 public void onCreate(Bundle savedInstanceState) {
    23
    24 super.onCreate(savedInstanceState);
    25
    26 photoservice = new PhotoService(this);
    27 initiallize();
    28 SimpleAdapter adapter = new SimpleAdapter(this, getData(),
    29 R.layout.listview, new String[] { "id", "name", "score" },
    30 new int[] { R.id.idview, R.id.nameview, R.id.scoreview });
    31 setListAdapter(adapter);
    32
    33 }
    34
    35 private void initiallize() {
    36 File[] dir = new File(Environment.getExternalStorageDirectory()
    37 .getPath() + "/DCIM").listFiles();
    38 File[] photolist = null;
    39 for (int i = 0; i < dir.length; i++) {
    40 if (dir[i].getName().startsWith("100")) {
    41 photolist = dir[i].listFiles();
    42 break;
    43 }
    44 }
    45 for (File file : photolist) {
    46 Photo photo = new Photo(file.getName(), 100);
    47 photos.add(photo);
    48 }
    49 photoservice.saveAll(photos);
    50 photoservice.find("ali_washing.jpg");
    51 photoservice.save(new Photo(1, "ali_help.jpg", 100));
    52 photoservice.update(new Photo(1, "ali_help.jpg", 20));
    53 photoservice.delete(photoservice.find("ali_help.jpg"));
    54 photoservice.clear();
    55
    56 }
    57
    58 private List<HashMap<String, String>> getData() {
    59
    60 List<HashMap<String, String>> data = new ArrayList<HashMap<String, String>>();
    61 HashMap<String, String> title = new HashMap<String, String>();
    62 title.put("id", "编号");
    63 title.put("name", "照片名");
    64 title.put("score", "照片得分");
    65 data.add(title);
    66 for (Photo photo : photos) {
    67 HashMap<String, String> map = new HashMap<String, String>();
    68 map.put("id", String.valueOf(photo.getId()));
    69 map.put("name", photo.getName());
    70 map.put("score", String.valueOf(photo.getScore()));
    71 data.add(map);
    72 }
    73 return data;
    74 }
    75 }



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  • 原文地址:https://www.cnblogs.com/bigmengzi/p/2283558.html
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