Java ANDROID:SQLite-ListView 2行

我想开始学习和理解SQlite，这就是为什么我开始在android开发者页面上尝试理解和编写记事本教程。但在ListView中，它们只显示您创建的注释的标题，而不显示正文。所以我想在ListView项目中显示标题和正文。这是我的密码：

NoteActivity类：

public class NoteActivity extends ListActivity
{
    private  static final ArrayList<HashMap<String,String>> list = new ArrayList<HashMap<String,String>>();
    private static final int ACTIVITY_CREATE=0;
    private static final int ACTIVITY_EDIT=1;
    private static final int INSERT_ID = Menu.FIRST;
    private static final int DELETE_ID = Menu.FIRST + 1;
    private NotesDbAdapter mDbHelper;


    Context ctx;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ctx = this;

        setContentView(R.layout.notepad_list);
        mDbHelper = new NotesDbAdapter(this);
        mDbHelper.open();
        fillData();

        registerForContextMenu(getListView());
    }

    private void fillData() {

        Cursor notesCursor = mDbHelper.fetchAllNotes();

        // Get all of the rows from the database and create the item list
        notesCursor = mDbHelper.fetchAllNotes();
        startManagingCursor(notesCursor);



         //This code works only to display the title in the ListView:
        /*
        // Create an array to specify the fields we want to display in the list (only TITLE)
        String[] from = new String[]{NotesDbAdapter.KEY_TITLE};

        // and an array of the fields we want to bind those fields to (in this case just text1)
        int[] to = new int[]{R.id.text1};

        // Now create a simple cursor adapter and set it to display
        SimpleCursorAdapter notes =new SimpleCursorAdapter(this, R.layout.notes_row, notesCursor, from, to);
        setListAdapter(notes);
        */


        //Here I want to use a SimpleAdapter to display the title and body of the Note
        SimpleAdapter adapter = new SimpleAdapter
                (this, list, R.layout.custom_row_view, new String[] {"title","body"}, new int[] {R.id.text11,R.id.text2});


        HashMap<String,String> temp = new HashMap<String,String>();
        temp.put("title",NotesDbAdapter.KEY_TITLE);
        temp.put("body", NotesDbAdapter.KEY_BODY);
        list.add(temp);

        setListAdapter(adapter);

    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        menu.add(0, INSERT_ID,0, R.string.menu_insert);
        return true;
    }

    @Override
    public boolean onMenuItemSelected(int featureId, MenuItem item) {

        switch(item.getItemId()) {
            case INSERT_ID:
                createNote();
                return true;
        }

        return super.onMenuItemSelected(featureId, item);
    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View v,
                                    ContextMenu.ContextMenuInfo menuInfo) {
        super.onCreateContextMenu(menu, v, menuInfo);

        menu.add(0,DELETE_ID,0,R.string.menu_delete);
    }

    @Override
    public boolean onContextItemSelected(MenuItem item) {

        switch (item.getItemId()){
            case DELETE_ID:
                AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
                mDbHelper.deleteNote(info.id);
                fillData();
                Toast.makeText(this,"Note deleted",Toast.LENGTH_SHORT).show();
                return true;
        }
        return super.onContextItemSelected(item);
    }

    private void createNote() {
        Intent intent = new Intent(this, NoteEdit.class);
        startActivityForResult(intent, ACTIVITY_CREATE);


    }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        super.onListItemClick(l, v, position, id);

        super.onListItemClick(l, v, position, id);
        Intent i = new Intent(this, NoteEdit.class);
        i.putExtra(NotesDbAdapter.KEY_ROWID, id);
        startActivityForResult(i, ACTIVITY_EDIT);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
        super.onActivityResult(requestCode, resultCode, intent);
        fillData();

    }

这是我的笔记Badapter类：

/** *简单notes数据库访问帮助器类。定义基本CRUD操作 *对于记事本示例，提供了列出所有注释以及 *检索或修改特定注释

*/ 公共类NotesBadapter{

private static final String DATABASE_NAME = "data";
private static final String DATABASE_TABLE = "notes";
private static final int DATABASE_VERSION = 2;


public static final String KEY_TITLE = "title";
public static final String KEY_BODY = "body";
public static final String KEY_ROWID = "_id";

private static final String TAG = "NotesDbAdapter";

private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;


private static final String DATABASE_CREATE =
    "create table notes (_id integer primary key autoincrement, "
    + "title text not null, body text not null);";


private final Context mCtx;


private static class DatabaseHelper extends SQLiteOpenHelper {

    DatabaseHelper(Context context) {

        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        db.execSQL(DATABASE_CREATE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
                + newVersion + ", which will destroy all old data");
        db.execSQL("DROP TABLE IF EXISTS notes");
        onCreate(db);
    }
}

/**
 * Constructor - takes the context to allow the database to be
 * opened/created
 *
 * @param ctx the Context within which to work

 */
public NotesDbAdapter(Context ctx) {
    this.mCtx = ctx;
}

/**
 * Open the notes database. If it cannot be opened, try to create a new
 * instance of the database. If it cannot be created, throw an exception to
 * signal the failure
 *
 * @return this (self reference, allowing this to be chained in an
 *         initialization call)
 * @throws android.database.SQLException if the database could be neither opened or created
 */
public NotesDbAdapter open() throws SQLException {
    mDbHelper = new DatabaseHelper(mCtx);
    mDb = mDbHelper.getWritableDatabase();
    return this;
}

public void close() {
    mDbHelper.close();
}

/**
 * Create a new note using the title and body provided. If the note is
 * successfully created return the new rowId for that note, otherwise return
 * a -1 to indicate failure.
 *
 * @param title the title of the note
 * @param body the body of the note

 */
public long createNote(String title, String body) {
    ContentValues initialValues = new ContentValues();
    initialValues.put(KEY_TITLE, title);
    initialValues.put(KEY_BODY, body);

    return mDb.insert(DATABASE_TABLE, null, initialValues);
}

/**
 * Delete the note with the given rowId
 * @param rowId id of note to delete
 * @return true if deleted, false otherwise
 */
public boolean deleteNote(long rowId) {

    return mDb.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}

/**
 * Return a Cursor over the list of all notes in the database
 *
 * @return Cursor over all notes
 */
public Cursor fetchAllNotes() {

    return mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_TITLE,
            KEY_BODY}, null, null, null, null, null);
}

/**
 * Return a Cursor positioned at the note that matches the given rowId
 * @param rowId id of note to retrieve
 * @return Cursor positioned to matching note, if found
 * @throws android.database.SQLException if note could not be found/retrieved
 */
public Cursor fetchNote(long rowId) throws SQLException {

    Cursor mCursor =

        mDb.query(true, DATABASE_TABLE, new String[] {KEY_ROWID,
                KEY_TITLE, KEY_BODY}, KEY_ROWID + "=" + rowId, null,
                null, null, null, null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }
    return mCursor;

}

/**
 * Update the note using the details provided. The note to be updated is
 * specified using the rowId, and it is altered to use the title and body
 * values passed in
 *
 * @param rowId id of note to update
 * @param title value to set note title to
 * @param body value to set note body to
 * @return true if the note was successfully updated, false otherwise
 */
public boolean updateNote(long rowId, String title, String body) {
    ContentValues args = new ContentValues();
    args.put(KEY_TITLE, title);
    args.put(KEY_BODY, body);

    return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}

}

我没有发布xml文件，因为我认为您不需要它们，主要问题是“fillData”方法，我不知道如何在listView中发布数据库中的2行

---

我还尝试了一些其他教程，但无法使其正常工作。据我所知，问题在于您的

fillData（）

方法。您将列名作为值而不是光标中的实际值传入

HashMap<String,String> temp = new HashMap<String,String>();
temp.put("title",NotesDbAdapter.KEY_TITLE);
temp.put("body", NotesDbAdapter.KEY_BODY);
list.add(temp);

HashMap temp=newhashmap（）；
临时输入（“标题”，注释注释辅助键（标题）；
温度输入（“主体”，注：键体）；
列表。添加（临时）；

这似乎是不正确的。相反，你应该按照以下思路做一些事情

private void fillData() {
    // Get all of the rows from the database and create the item list
    Cursor notesCursor = mDbHelper.fetchAllNotes();
    startManagingCursor(notesCursor);

    // The list that will back our table, this could be turned into a member variable.
    List<HashMap<String,String>> list = new ArrayList<HashMap<String,String>>();

    // Get the column indexes
    int titleColumnIndex = notesCursor.getColumnIndex(NotesDbAdapter.KEY_TITLE);
    int bodyColumnIndex = notesCursor.getColumnIndex(NotesDbAdapter.KEY_BODY);

    // Iterate through all of the cursor rows to fill the adapter
    while (notesCursor.moveToNext()) {
        String title = notesCursor.getString(titleColumnIndex);
        String body = notesCursor.getString(bodyColumnIndex);

        HashMap<String,String> temp = new HashMap<String,String>();
        temp.put("title", title);
        temp.put("body", body);
        list.add(temp);
    }

    //Here I want to use a SimpleAdapter to display the title and body of the Note
    SimpleAdapter adapter = new SimpleAdapter
            (this, list, R.layout.custom_row_view, new String[] {"title","body"}, new int[] {R.id.text11,R.id.text2});
    setListAdapter(adapter);
}

private void fillData（）{
//从数据库中获取所有行并创建项目列表
游标notescrsor=mDbHelper.fetchAllNotes（）；
开始标记光标（notescrsor）；
//支持我们的表的列表，可以将其转换为成员变量。
列表=新的ArrayList（）；
//获取列索引
int titleColumnIndex=notesCursor.getColumnIndex（NotesDbAdapter.KEY\u TITLE）；
int-bodyColumnIndex=notescrsor.getColumnIndex（NotesDbAdapter.KEY\u-BODY）；
//遍历所有光标行以填充适配器
while（notescrsors.moveToNext（））{
String title=notescrsor.getString（titleColumnIndex）；
String body=notesCursor.getString（bodyColumnIndex）；
HashMap temp=新的HashMap（）；
临时投入（“标题”，标题）；
温度放置（“主体”，主体）；
列表。添加（临时）；
}
//这里我想使用SimpleAdapter来显示注释的标题和正文
SimpleAdapter适配器=新SimpleAdapter
（这个，列表，R.layout.custom_row_视图，新字符串[]{“title”，“body”}，新int[]{R.id.text11，R.id.text2}）；
setListAdapter（适配器）；
}

更多关于as的信息，您将在Android中处理数据库时非常广泛地使用它

---

另外，要获得关于使用游标的可能更清晰的答案，请查看此链接。

我建议将代码粘贴到此处，而不是链接到它。确保你使用“块代码”样式。是的，但我认为它太长，太难阅读，我想如果我只是发布链接，它会更清晰，而不是一直滚动我理解，但最好粘贴在这里：你在未来发布的链接可能不再可访问，这可能会引起其他人的兴趣。此外，在某些国家，该网站可能被屏蔽（例如我的网站），我无法查看代码以帮助您。是的，您是对的，sorryAre

NotesDbAdapter.KEY\u TITLE

和

NotesDbAdapter.KEY\u BODY

是指数据库中的列名吗？是的，这应该取代最初在fillData（）方法中构建HashMap的位置。那么您是指使用我用来从数据库中获取行的游标吗？：Cursor notescursors=mDbHelper.fetchAllNotes（）; notesCursor=mDbHelper.fetchAllNotes（）；开始标记光标（notescrsor）；sry我是新来的..不知道如何格式化这些小注释中的代码我在我的答案中添加了更多的上下文。是的，sry很想再次打扰你，但现在的问题是，如果我使用String title=notesCursor.getString（NotesDbAdapter.KEY\u title）；IDE将其标记为错误，因为getString需要一个int作为参数，确切的错误是：getString（int）不能应用于（java.lang.String）

private void fillData() {
    // Get all of the rows from the database and create the item list
    Cursor notesCursor = mDbHelper.fetchAllNotes();
    startManagingCursor(notesCursor);

    // The list that will back our table, this could be turned into a member variable.
    List<HashMap<String,String>> list = new ArrayList<HashMap<String,String>>();

    // Get the column indexes
    int titleColumnIndex = notesCursor.getColumnIndex(NotesDbAdapter.KEY_TITLE);
    int bodyColumnIndex = notesCursor.getColumnIndex(NotesDbAdapter.KEY_BODY);

    // Iterate through all of the cursor rows to fill the adapter
    while (notesCursor.moveToNext()) {
        String title = notesCursor.getString(titleColumnIndex);
        String body = notesCursor.getString(bodyColumnIndex);

        HashMap<String,String> temp = new HashMap<String,String>();
        temp.put("title", title);
        temp.put("body", body);
        list.add(temp);
    }

    //Here I want to use a SimpleAdapter to display the title and body of the Note
    SimpleAdapter adapter = new SimpleAdapter
            (this, list, R.layout.custom_row_view, new String[] {"title","body"}, new int[] {R.id.text11,R.id.text2});
    setListAdapter(adapter);
}