用于编辑文本的Android列表视图任务

Question

我有一个连接到数据库的android ListView应用程序。我希望有人能够编辑他们点击的listView。当他们长时间点击时，它会为他们带来两个不同的活动，包括文本视图和保存按钮。我想要的是textview有正在编辑的项目的文本。

例如：

 Intent b = new Intent(MainActivity.this, Test.class);
            b.putExtra(Rd, String.valueOf(id)); 

获取数据库行标识并将其变为字符串^

// Puts Id Of Last Clicked List View Item Into String//
public final static String Rd = DBAdapter.KEY_ROWID;

取字符串并使其成为全局^

    // Gets Id Of Last Clicked List View Item//
    passedVar = getIntent().getStringExtra(MainActivity.Rd);

    // Links Variable etTasks To Physical Edit Text In Layout//
    etTasks = (EditText) findViewById(R.id.editTextTask);
    etTasks.setText(passedVar);

然后允许在编辑文本^

中查看数字或ROW_ID

我想做同样的事情，但是列表视图项中的文本内容不是数据库的行id。请帮助谢谢。

这是我的其余代码。

将对DBAdapter：

public class DBAdapter {

private static final String TAG = "DBAdapter"; //used for logging 
database version changes

// Field Names:
public static final String KEY_ROWID = "_id";
public static final String KEY_TASK = "task";
public static final String KEY_DATE = "date";

public static final String[] ALL_KEYS = new String[] {KEY_ROWID, KEY_TASK, KEY_DATE};

// Column Numbers for each Field Name:
public static final int COL_ROWID = 0;
public static final int COL_TASK = 1;
public static final int COL_DATE = 2;

// DataBase info:
public static final String DATABASE_NAME = "dbToDo";
public static final String DATABASE_TABLE = "mainToDo";
public static final int DATABASE_VERSION = 1; // The version number must be incremented each time a change to DB structure occurs.

//SQL statement to create database
private static final String DATABASE_CREATE_SQL = 
        "CREATE TABLE " + DATABASE_TABLE 
        + " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
        + KEY_TASK + " TEXT NOT NULL, "
        + KEY_DATE + " TEXT"
        + ");";

private final Context context;
private DatabaseHelper myDBHelper;
private SQLiteDatabase db;


public DBAdapter(Context ctx) {
    this.context = ctx;
    myDBHelper = new DatabaseHelper(context);
}

// Open the database connection.
public DBAdapter open() {
    db = myDBHelper.getWritableDatabase();
    return this;
}

// Close the database connection.
public void close() {
    myDBHelper.close();
}

// Add a new set of values to be inserted into the database.
public long insertRow(String task, String date) {
    ContentValues initialValues = new ContentValues();
    initialValues.put(KEY_TASK, task);
    initialValues.put(KEY_DATE, date);

    // Insert the data into the database.
    return db.insert(DATABASE_TABLE, null, initialValues);
}

// Delete a row from the database, by rowId (primary key)
public boolean deleteRow(long rowId) {
    String where = KEY_ROWID + "=" + rowId;
    return db.delete(DATABASE_TABLE, where, null) != 0;
}

public void deleteAll() {
    Cursor c = getAllRows();
    long rowId = c.getColumnIndexOrThrow(KEY_ROWID);
    if (c.moveToFirst()) {
        do {
            deleteRow(c.getLong((int) rowId));              
        } while (c.moveToNext());
    }
    c.close();
}

// Return all data in the database.
public Cursor getAllRows() {
    String where = null;
    Cursor c =  db.query(true, DATABASE_TABLE, ALL_KEYS, where, null, null, null, null, null);
    if (c != null) {
        c.moveToFirst();
    }
    return c;
}

// Get a specific row (by rowId)
public Cursor getRow(String rowId) {
    String where = KEY_ROWID + "=" + rowId;
    Cursor c =  db.query(true, DATABASE_TABLE, ALL_KEYS, 
                    where, null, null, null, null, null);
    if (c != null) {
        c.moveToFirst();
    }
    return c;
}

// Change an existing row to be equal to new data.
public boolean updateRow(String rowId, String task, String date) {
    String where = KEY_ROWID + "=" + rowId;
    ContentValues newValues = new ContentValues();
    newValues.put(KEY_TASK, task);
    newValues.put(KEY_DATE, date);
    // Insert it into the database.
    return db.update(DATABASE_TABLE, newValues, where, null) != 0;
}

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_SQL);           
    }

    @Override
    public void onUpgrade(SQLiteDatabase _db, int oldVersion, int newVersion) {
        Log.w(TAG, "Upgrading application's database from version " + oldVersion
                + " to " + newVersion + ", which will destroy all old data!");

        // Destroy old database:
        _db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);

        // Recreate new database:
        onCreate(_db);
      }
  }


}

主要活动：

public class MainActivity extends ActionBarActivity implements   
.OnClickListener {

// Connect To Database MyDb//
DBAdapter myDb;

// Defines Variable ListView MyList//
ListView mylist;

// Defines Variable ListView Adapter//
SimpleCursorAdapter myCursorAdapter;

// Defines Variable Database Cursor//
Cursor cursor;

// Defines Variable Connected To Database String//
String[] fromFieldNames;

// Defines Variable That Takes String From Database//
int[] toViewIDs;

// Puts Id Of Last Clicked List View Item Into String//
public final static String Rd = DBAdapter.KEY_ROWID;

// Puts Task Of Last Clicked List View Item Into String//
public final static String Sd = DBAdapter.KEY_TASK;

// What Happens When Activity Starts//
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Links Variable MyList To Physical ListView In Layout//
    mylist = (ListView) findViewById(R.id.listView);

    // Links Variable Button2 to Physical Button In Layout//
    Button option = (Button) findViewById(R.id.button2);
    option.setOnClickListener(this);

    // Controls What Happens When ListView Is Long Clicked//
    mylist.setOnItemLongClickListener(new ListView.OnItemLongClickListener() {

        @Override
        public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int position, long id) {

            Intent b = new Intent(MainActivity.this, Test.class);
            b.putExtra(Rd, String.valueOf(id));
            b.putExtra(Sd, String.valueOf(toViewIDs));
            startActivity(b);

            return true;
        }
    });

    // Opens Database//
    openDB();

    // Shows Whats Stored In Database In A List View//
    populateListView();
}

// What Happens When Said Button Is Clicked//
@Override
public void onClick(View v) {
    switch (v.getId()) {

        // What Happens When Button Two Is Clicked//
        case R.id.button2:

            // Open Activity Test//
            Intent i = new Intent(this, Test.class);
            startActivity(i);
        break;
    }
}

// Method To Open Database//
private void openDB() {

    // Links Variable myDb To Database//
    myDb = new DBAdapter(this);

    // Opens Database//
    myDb.open();
}

// Method To Populate ListViews From Database//
private void populateListView() {

    // Gets All Rows Added To Database//
    cursor = myDb.getAllRows();

    // Puts Rows Stored On Database Into A String (DBAdapter.KEY_ROWID = Numbers Each Row In ListView, KEY_TASK = Information Shown By You//
    fromFieldNames = new String[]{DBAdapter.KEY_ROWID, DBAdapter.KEY_TASK,};

    // Takes String From Database And Sends It To Whatever Layout Widget You Want. Will Show Up In The Order String Is Made In//
    toViewIDs = new int[]{R.id.textViewItemNumber, R.id.textViewItemTask};

    // Creates ListView Adapter Which Allows ListView Items To Be Seen//
    myCursorAdapter = new SimpleCursorAdapter(getBaseContext(), R.layout.item_layout, cursor, fromFieldNames, toViewIDs, 0);

    // Sets Up Adapter Made Earlier / Shows Content From Database//
    mylist.setAdapter(myCursorAdapter);
  }

}

的Test.class：

public class Test extends ActionBarActivity {

// Sets Item In ListView To The Current Date It Mas Made//
Time today = new Time(Time.getCurrentTimezone());

// Connect To Database//
DBAdapter myDb;

// Defines Variable EditText//
public static EditText etTasks;

public static TextView passedView;

String passedVar = null;

String passedVar2 = null;

// Defines String Variable For Date In Update Task//
String date;

// Defines String Variable For Task In Update Task//
String task;

// Defines Variable Database Cursor//
Cursor cursor;

// What Happens When Activity Starts//
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test);

    // Gets Id Of Last Clicked List View Item//
    passedVar = getIntent().getStringExtra(MainActivity.Rd);

    // Gets Id Of Last Clicked List View Item//
    passedVar2 = getIntent().getStringExtra(MainActivity.Sd);

    // Links Variable etTasks To Physical Edit Text In Layout//
    etTasks = (EditText) findViewById(R.id.editTextTask);
    etTasks.setText(passedVar2);

    //Opens DataBase//
    openDB();
}

// Method To Open Database//
private void openDB() {

    // Links Variable myDb To Database//
    myDb = new DBAdapter(this);

    // Opens Database//
    myDb.open();
}

// What Happens When Add Button Is Clicked//
public void onClick_AddTask(View v) {

    // Set New Database Entry To Current Time//
    today.setToNow();

    // Sets Time In Format Understandable To Humans//
    String timestamp = today.format("%y-%m-%d %H:%M:%S");

    // Takes Whats In Edit Text And Turns It Into A String//
    if (!TextUtils.isEmpty(etTasks.getText().toString())) {

        // Inserts It Into Database//
        myDb.insertRow(etTasks.getText().toString(), timestamp);
    }

    // Sets PassedView To Null//
    passedView = null;

    // Starts Options Activity//
    Intent i = new Intent(this, MainActivity.class);
    startActivity(i);
}

// What Happens When Add Button Is Clicked//
public void editListView(View v) {

    updateTask(DEFAULT_KEYS_DIALER);
}

// Method That Updates Task//
private void updateTask(long id) {

        // Gets Selected Row//
        cursor = myDb.getRow(passedVar);

        // Where New Updated Content Comes From//
        task = etTasks.getText().toString();

        // Set New Database Entry To Current Time//
        today.setToNow();

        // Sets Time In Format Understandable To Humans//
        date = today.format("%y-%m-%d %H:%M:%S");

        // Updates Specific Row In Database//
        myDb.updateRow(passedVar, task, date);

        // Closes Cursor//
        cursor.close();

        Intent i = new Intent(this, MainActivity.class);
        startActivity(i);
     }
  }