drawable getResources().getIdentifier问题

Question

这是我第一次来这里(我觉得这个网站很有用).我是android的新手,我需要找出为什么我无法在列表视图中动态加载图像.

我有三个字符串数组:

private String lv_arr[]={"News", 
        "Events", 
        "Other"};
private String lv_arr_d[]={"Get the latest news", 
        "Latest events", 
        "Other description here"};
private String lv_arr_icons[]={"news", "events", "other"};

我的列表在左侧显示一个图标,在每个列表项中右侧显示两行文本.当我硬编码图像的名称(例如新闻)时,它工作正常.

ArrayList <HashMap <String, Object>> users = 
     new ArrayList <HashMap <String, Object>> ();
     int l = lv_arr.length;
     for (int i = 0; i <l; i++) {
     HashMap <String, Object> user = new HashMap <String, Object> ();

     //get icons
     String uri = "drawable/"+lv_arr_icons[i];

     user.put ( "icon", (Drawable)getResources().getDrawable(
             getResources().getIdentifier(uri, null, getPackageName())));
//the above works ok if i set R.drawable.news 
     user.put ( "label", lv_arr[i].toString()); 
     user.put ( "description",  lv_arr_d[i].toString()); 
     users.add (user); 
     }

     String[] names = {"icon", "label", "description"};
     int[] views = {R.id.icon, R.id.label, R.id.description};

     SimpleAdapter saImageItems = new SimpleAdapter(this.getApplicationContext(), 
             users,  R.layout.optionslistitem, names, views);
       lv1.setAdapter(saImageItems); //lv1 is my ListView

所有图像都在drawable文件夹中.当我试图传递他们的名字并从资源中获取它们时,为什么没有图像加载的任何想法？

Answer 1

如果你这样做会怎么样:

user.put ( "icon", getResources().getIdentifier(uri, "drawable", getPackageName()));

Answer 2

这是一个辅助函数

public static int getDrawable(Context context, String name)
{
    Assert.assertNotNull(context);
    Assert.assertNotNull(name);

    return context.getResources().getIdentifier(name,
            "drawable", context.getPackageName());
}