从 SQLite 数据库在 ListView 中显示图像

Question

我现在有点卡住了。我知道有人问过类似的问题，但我找不到任何有帮助的东西。

我正在尝试从我的 android 应用程序的内部数据库中获取并显示在 ListView 中的图像。我有一个包含 141 行的数据库，每行标记为 1,2 或 3。我需要不同的 png 图像（保存在我的 res/drawable 文件夹中）来显示取决于 1,2 或 3。这是我当前的询问。任何的建议都受欢迎。我意识到可能有更好的方式来显示我需要的信息。

   public void whosnext(View view) {
    // || is the concatenation operation in SQLite
    cursor = db.rawQuery("SELECT * FROM eventsv1 WHERE start_time > (DATETIME('now')) AND title LIKE ? ORDER BY date ASC, time DESC", 
                    new String[]{"%" + searchText.getText().toString() + "%"});
    adapter = new SimpleCursorAdapter(
            this, 
            R.layout.artist_list_item, 
            cursor, 
            new String[] {"title", "time", "date", "title3", "style"}, 
            new int[] {R.id.title, R.id.time, R.id.date, R.id.title3, R.id.style});
    setListAdapter(adapter);
}

Answer 1

我会写一个自定义 CursorAdapter

public class WhosNextAdapter extends CursorAdapter
{
    public WhosNextAdapter(Context context, Cursor cursor, boolean autoRequery) {
        super(context, cursor, autoRequery);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        //This is were you would check your cursor for style (I think that is 1,2,3 your column)
        int style = cursor.getInt(cursor.getColumnIndex("style"));

        ImageView img = (ImageView) view.findViewById(R.id.yourImageViewId);

        switch (style) {
            case 1:
                img.setImageResource(R.drawable.yourImageForStyle1);

            break;
            case 2:
                img.setImageResource(R.drawable.yourImageForStyle2);

            break;

//etc.
        }
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        //Inflate layout R.layout.artist_list_item

        //Call bindView passing inflated layout, context, and cursor

        //return layout
    }
}

Answer 2

您肯定需要扩展SimpleCursorAdapter，如果您的项目布局足够简单，您唯一需要做的就是覆盖setViewImage() 方法，您只需从数据库中转换提供的值并调用setImageResource() 方法ImageView 对象。这样您就不必更改很多附加代码。

public class MySimpleCursorAdpater extends SimpleCursorAdapter {

    public MySimpleCursorAdpater(Context context, int layout, Cursor c,
            String[] from, int[] to) {
        super(context, layout, c, from, to);
    }

    @Override
    public void setViewImage(ImageView v, String value) {
        /*your code to convert value from database to drawable resource id*/
        v.setImageResource(resourceId);
    }

}