Java 在Android studio中创建预期分号
我在private void updateUI上一直看到一个红色标记,其中显示了一条错误消息,显示express预期的分号。尝试以下操作:Java 在Android studio中创建预期分号,java,android,android-studio,oncreate,Java,Android,Android Studio,Oncreate,我在private void updateUI上一直看到一个红色标记,其中显示了一条错误消息,显示express预期的分号。尝试以下操作: public class MainActivity extends AppCompatActivity { private TaskDBHelper helper; private ListAdapter listAdapter; @Override public void onCrea
public class MainActivity extends AppCompatActivity {
private TaskDBHelper helper;
private ListAdapter listAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
private void updateUI(){
helper = new TaskDBHelper(MainActivity.this);
SQLiteDatabase sqlDB = helper.getReadableDatabase();
Cursor cursor = sqlDB.query(TaskContract.TABLE,
new String[]{TaskContract.Columns._ID, TaskContract.Columns.TASK},
null, null, null, null, null);
listAdapter = new SimpleCursorAdapter(
this,
R.layout.task_view,
cursor,
new String[]{TaskContract.Columns.TASK},
new int[]{R.id.taskTextView},
0
);
ListView listView = (ListView) findViewById(R.id.list);
listView.setAdapter(listAdapter);
}
}
}
在Java中,不能在另一个方法的作用域内声明一个方法。只能在类的作用域内声明方法。因此,您声明方法updateUI的方式无效,应该移动到类作用域。您在oncreate method中调用methodupdateUi方法实现中的方法。它说重写方法应该调用super.oncreateupdated它。添加此行:super.onCreatesavedInstanceState;顺便说一句,在onCreate:setContentViewR.layout.your_活动之后,您也需要设置布局;
public class MainActivity extends AppCompatActivity {
private TaskDBHelper helper;
private ListAdapter listAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
updateUI();
ListView listView = (ListView) findViewById(R.id.list);
listView.setAdapter(listAdapter);
}
private void updateUI(){
helper = new TaskDBHelper(MainActivity.this);
SQLiteDatabase sqlDB = helper.getReadableDatabase();
Cursor cursor = sqlDB.query(TaskContract.TABLE,
new String[]{TaskContract.Columns._ID, TaskContract.Columns.TASK},
null, null, null, null, null);
listAdapter = new SimpleCursorAdapter(
this,
R.layout.task_view,
cursor,
new String[]{TaskContract.Columns.TASK},
new int[]{R.id.taskTextView},
0
);
}
}