用户输入文本时如何使用光标更新列表视图

Question

我完全被难住了！我已经寻找了很长时间，但找不到解决方案。我有一种感觉，这会很容易！

不管怎样，我有一个绑定到光标的列表视图，每次用户输入字母时，我希望列表视图搜索数据库并返回结果。听起来很简单，但我无法弄清楚。预先感谢您的帮助。

这是我到目前为止的代码：

public class MyList extends ListActivity {


    public static final String KEY_ROWID = "headwords._id";
    public static final String KEY_WORDS = "headwords.words";
    private ListAdapter adapter;
    private DbManager myDb;


    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.item_list);


        myDb = new DbManager(this);
        myDb.open();
        Cursor mCursor = myDb.startsWith("a");
        startManagingCursor(mCursor);



        try {
        adapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, mCursor, 
                new String[] { KEY_WORDS, KEY_ROWID },
                new int[] { android.R.id.text1, android.R.id.text2 });
                setListAdapter(adapter);

        } catch (Exception e) {
            Log.i("adapter error Here!", ">>>>>>>>>>> Error!" + e.toString());
        }








        EditText myET = (EditText) findViewById(R.id.search_text);
        myET.addTextChangedListener(new TextWatcher() {
            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                //code which would change listview to only show item that match what is being typed in
            }

            @Override
            public void afterTextChanged(Editable s) {
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after) {    
            }

        });

    }

Answer 1

首先使 mCursor 成为成员：

private Cursor mCursor;

@Override
public void onCreate(Bundle icicle) {
  mCursor = myDb.startsWith("a");
}

然后在我的示例中，我采用 CharSequence 的第一个字母，但这可能不是您想要做的，但关键是 changeCursor();

@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
  mCursor = myDb.startsWith(s.toString.substring(0,1));
  adapter.changeCursor(mCursor);
}