键值观察对UITextView的Text属性有效吗？

问题描述

| 使用UITextView的text属性观察键值时，我遇到最糟糕的时间。我可以成功添加观察者，甚至可以删除该观察者。我有一个包含多个单元格的tableview-一些具有UITextField，一些具有UISegmentSelectors，一个具有UITextView。我的核心数据对象（NSMangedObject的子类）除UITextView之外，均已成功观察到所有其他字段。如果需要，我可以发布代码。 邮编：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *UserProfileCellIdentifier = @\"UserProfileCellIdentifier\";

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:
                         UserProfileCellIdentifier];
if (cell == nil) 
{
    [_tableCellsNib instantiateWithOwner:self options:nil];

    switch (indexPath.row)
    {
            // UserName Row
        case UserNameRowIndex:
            _textFieldCell.cellLabel.text = NSLocalizedString(@\"UserNameLabel\",@\"User Profile TableView\");
            _textFieldCell.cellType = CellTypeNormal;
            _textFieldCell.boundProperty = @\"UserName\";
            _textFieldCell.tag = indexPath.row;
            _textFieldCell.errorHandler = self;
            _textFieldCell.boundControl = _textFieldCell.cellTextField;

            [_textFieldCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellTextField.text\" options:NSKeyValueObservingOptionNew context:NULL];

            cell = _textFieldCell;

            self.textFieldCell = nil;
            break;
        case PasswordRowIndex:
            _textFieldCell.cellLabel.text = NSLocalizedString(@\"PasswordLabel\",@\"User Profile TableView\");
            _textFieldCell.cellType = CellTypeNormal;
            _textFieldCell.cellTextField.secureTextEntry = YES;
            _textFieldCell.boundProperty = @\"Password\";
            _textFieldCell.tag = indexPath.row;
            _textFieldCell.errorHandler = self;
            _textFieldCell.boundControl = _textFieldCell.cellTextField;

            [_textFieldCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellTextField.text\" options:NSKeyValueObservingOptionNew context:NULL];

            cell = _textFieldCell;

            self.textFieldCell = nil;
            break;
        case PasswordConfirmRowIndex:
            _textFieldCell.cellLabel.text = NSLocalizedString(@\"PasswordConfirmLabel\",@\"User Profile TableView\");
            _textFieldCell.cellType = CellTypeNormal;
            _textFieldCell.cellTextField.secureTextEntry = YES;
            _textFieldCell.tag = indexPath.row;

            cell = _textFieldCell;

            self.textFieldCell = nil;
            break;
        case FirstNameRowIndex:
            _textFieldCell.cellLabel.text = NSLocalizedString(@\"FirstNameLabel\",@\"User Profile TableView\");
            _textFieldCell.cellType = CellTypeNormal;
            _textFieldCell.boundProperty = @\"FirstName\";
            _textFieldCell.tag = indexPath.row;
            _textFieldCell.errorHandler = self;
            _textFieldCell.boundControl = _textFieldCell.cellTextField;

            [_textFieldCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellTextField.text\" options:NSKeyValueObservingOptionNew context:NULL];
            cell = _textFieldCell;

            self.textFieldCell = nil;
            break;
        case LastNameRowIndex:
            _textFieldCell.cellLabel.text = NSLocalizedString(@\"LastNameLabel\",@\"User Profile TableView\");
            _textFieldCell.cellType = CellTypeNormal;
            _textFieldCell.boundProperty = @\"LastName\";
            _textFieldCell.tag = indexPath.row;
            _textFieldCell.errorHandler = self;
            _textFieldCell.boundControl = _textFieldCell.cellTextField;

            [_textFieldCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellTextField.text\" options:NSKeyValueObservingOptionNew context:NULL];
            cell = _textFieldCell;

            self.textFieldCell = nil;
            break;
        case DateOfBirthRowIndex:
            _textFieldCell.cellLabel.text = NSLocalizedString(@\"BirthDateLabel\",@\"User Profile TableView\");
            _textFieldCell.cellType = CellTypeDatePicker;
            _textFieldCell.boundProperty = @\"DateOfBirth\";
            _textFieldCell.tag = indexPath.row;
            _textFieldCell.errorHandler = self;
            _textFieldCell.boundControl = _textFieldCell.cellTextField;

            [_textFieldCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellTextField.text\" options:NSKeyValueObservingOptionNew context:NULL];
            cell = _textFieldCell;

            self.textFieldCell = nil;
            break;
        case GenderSelfRowIndex:
            _genderSelectCell.cellLabel.text = NSLocalizedString(@\"UserSexLabel\",@\"User Profile TableView\");
            _genderSelectCell.boundProperty = @\"GenderSelf\";
            _genderSelectCell.errorHandler = self;
            _genderSelectCell.boundControl = _genderSelectCell.cellGenderSegment;
            _genderSelectCell.tag = indexPath.row;

            [_genderSelectCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellGenderSegment.selectedSegmentIndex\" options:NSKeyValueObservingOptionNew context:NULL];
            cell = _genderSelectCell;

            self.genderSelectCell = nil;
            break;
        case GenderInterestedInRowIndex:
            _genderSelectCell.cellLabel.text = NSLocalizedString(@\"UserInterestedInLabel\",@\"User Profile TableView\");
            _genderSelectCell.boundProperty = @\"GenderInterestedIn\";
            _genderSelectCell.errorHandler = self;
            _genderSelectCell.boundControl = _genderSelectCell.cellGenderSegment;
            _genderSelectCell.tag = indexPath.row;

            [_genderSelectCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellGenderSegment.selectedSegmentIndex\" options:NSKeyValueObservingOptionNew context:NULL];
            cell = _genderSelectCell;

            self.genderSelectCell = nil;
            break;
        case IntroductionRowIndex:
            _textViewCell.cellLabel.text = NSLocalizedString(@\"IntroductionLabel\",@\"User Profile TableView\");
            _textViewCell.boundControl = _textViewCell.cellTextView;
            _textViewCell.errorHandler = self;
            _textViewCell.boundProperty = @\"Introduction\";
            _textViewCell.tag = indexPath.row;

            [_textViewCell addObserver:[MBUtilities getAppDelegate].userProfile forKeyPath:@\"cellTextView.text\" options:NSKeyValueObservingOptionNew context:NULL];
            cell = _textViewCell;

            self.textViewCell = nil;
            break;
    };
}

return cell;
}

讨论：每个单元都是从外部NIB文件加载的，然后使用不同的属性进行初始化。除了最后一个带有UITextView的单元格外，所有单元格都可以观察键值。让我知道是否需要其他信息。     

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

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