tableView 滚动时添加了重复的 UITextField
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【中文标题】tableView 滚动时添加了重复的 UITextField【英文标题】：Duplicate UITextField's being added when tableView scrolls 【发布时间】：2014-02-11 14:59:20 【问题描述】：我遇到了一个问题，即重复使用单元格时添加了重复的 UITextField，这不是我想要发生的。我记得以前遇到过类似的问题，但是对于我的生活，我不记得我做了什么来解决它。
毫无疑问，这很明显，但我似乎找不到任何有用的东西。正如某些人所建议的那样，我已经尝试将 if/else 语句包含在“if (cell == null)”中，但这只会导致形成一个空白表。
我们将不胜感激一些建议。
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (indexPath.section == 0)
productField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[productField setPlaceholder:@"Product"];
if ([productData length] > 0)
[productField setText:productData];
[productField setEnabled:false];
[cell addSubview:productField];
else if (indexPath.section == 1)
issueField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[issueField setPlaceholder:@"What's the issue?"];
[issueField setAutocorrectionType:UITextAutocorrectionTypeNo];
[cell addSubview:issueField];
else if (indexPath.section == 2)
emailField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[emailField setPlaceholder:@"Email address"];
[emailField setAutocorrectionType:UITextAutocorrectionTypeNo];
[emailField setAutocapitalizationType:UITextAutocapitalizationTypeNone];
[emailField setKeyboardType:UIKeyboardTypeEmailAddress];
[cell addSubview:emailField];
else if (indexPath.section == 3)
notesField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[notesField setPlaceholder:@"Any notes to add?"];
[notesField setAutocorrectionType:UITextAutocorrectionTypeNo];
[cell addSubview:notesField];
else if (indexPath.section == 4)
sendFeedback = [[UIButton alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[sendFeedback setTitle:@"Send Feedback" forState:UIControlStateNormal];
[sendFeedback setBackgroundColor:[UIColor colorWithRed:(111/255.0f) green:(31/255.0f) blue:(68/255.0f) alpha:1.0f]];
[sendFeedback.titleLabel setFont:[UIFont fontWithName:@"MaryAnn" size:20.0]];
[sendFeedback addTarget:self action:@selector(sendFeedback:) forControlEvents:UIControlEventTouchUpInside];
[cell setBackgroundColor:[UIColor clearColor]];
[cell addSubview:sendFeedback];
return cell;
【问题讨论】：
你应该使用静态单元格代替 dequeueReusableCell 它们。 你不能创建自定义单元格吗？ 感谢您的帮助。我选择了静态单元格（完全忘记了它们），因为它只会在测试版本中使用，而不是在应用程序的生产版本中使用。 【参考方案1】：你的问题是表格视图中的可重用单元格，试试这个代码
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if(cell == nil)
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
cell.selectionStyle=UITableViewCellSelectionStyleNone;
UITextField* textField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
textField.tag=101;
[cell addSubview:textField];
UIButton *sendFeedback = [[UIButton alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
sendFeedback.tag=102;
[sendFeedback setTitle:@"Send Feedback" forState:UIControlStateNormal];
[sendFeedback setBackgroundColor:[UIColor colorWithRed:(111/255.0f) green:(31/255.0f) blue:(68/255.0f) alpha:1.0f]];
[sendFeedback.titleLabel setFont:[UIFont fontWithName:@"MaryAnn" size:20.0]];
[sendFeedback addTarget:self action:@selector(sendFeedback:) forControlEvents:UIControlEventTouchUpInside];
[cell setBackgroundColor:[UIColor clearColor]];
[cell addSubview:sendFeedback];
UITextField* textField=(UITextField*)[cell viewWithTag:101];
UIButton *sendFeedback = (UIButton*)[cell viewWithTag:102];
sendFeedback.hidden=YES;
textField.hidden=NO;
[textField setKeyboardType:UIKeyboardTypeDefault];
if (indexPath.section == 0)
[textField setPlaceholder:@"Product"];
if ([productData length] > 0)
[textField setText:productData];
[textField setEnabled:false];
else if (indexPath.section == 1)
[textField setPlaceholder:@"What's the issue?"];
[textField setAutocorrectionType:UITextAutocorrectionTypeNo];
else if (indexPath.section == 2)
[textField setPlaceholder:@"Email address"];
[textField setAutocorrectionType:UITextAutocorrectionTypeNo];
[textField setAutocapitalizationType:UITextAutocapitalizationTypeNone];
[textField setKeyboardType:UIKeyboardTypeEmailAddress];
else if (indexPath.section == 3)
[textField setPlaceholder:@"Any notes to add?"];
[textField setAutocorrectionType:UITextAutocorrectionTypeNo];
else if (indexPath.section == 4)
textField.hidden=YES;
sendFeedback.hidden=NO;
return cell;
// 在表格视图中不能直接访问 textField.text，而是使用全局变量或字典来分配 textField.text
【讨论】：
【参考方案2】：这是因为您不断将子视图添加到单元格中。例如，您将 productField 添加到索引 0 处的单元格。当该单元格被重用时，您向其添加另一个子视图，但 productField 仍然存在。一种可能的解决方案是在添加新子视图之前删除子视图。你的if 声明会是这样的：
if (indexPath.section == 0)
// Remove the old subview
UIView *oldSubview = [cell viewWithTag:5];
[oldSubview removeFromSuperview];
productField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[productField setPlaceholder:@"Product"];
if ([productData length] > 0)
[productField setText:productData];
[productField setEnabled:false];
// Set a tag for the new subview, so you can remove it later
productField.tag = 5;
[cell addSubview:productField];
在每个if 语句中使用相同的tag。
编辑：
或者你也可以像@pawan 建议的那样使用静态单元格。
【讨论】：
【参考方案3】：问题在于，由于您正在回收单元格（并且应该），因此您正在重用非空单元格并在其上添加新控件。
通常的处理方法是构建您的自定义 UITableViewCell 子类，并将各种文本字段和其他 UI 控件作为属性。 然后您可以在每个部分中显示/隐藏这些 UI 控件
看起来像这样：
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
static NSString *CellIdentifier = @"Cell";
CustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (indexPath.section == 0)
productField.hidden=NO;
issueField.hidden=YES;
else if (indexPath.section == 1)
productField.hidden=YES;
issueField.hidden=NO;
return cell;
【讨论】：
【参考方案4】：为什么不实例化单元格后，从单元格内容视图中删除所有子视图
for( UIView *view in cell.contentView.subviews )
[view removeFromSuperview];
【讨论】：
【参考方案5】：- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
NSString *CellIdentifier = [NSString stringWithFormat:@"Cell %d",indexPath.section];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
cell = nil;
if (cell == nil)
if (indexPath.section == 0)
productField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[productField setPlaceholder:@"Product"];
if ([productData length] > 0)
[productField setText:productData];
[productField setEnabled:false];
[cell addSubview:productField];
else if (indexPath.section == 1)
issueField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[issueField setPlaceholder:@"What's the issue?"];
[issueField setAutocorrectionType:UITextAutocorrectionTypeNo];
[cell addSubview:issueField];
else if (indexPath.section == 2)
emailField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[emailField setPlaceholder:@"Email address"];
[emailField setAutocorrectionType:UITextAutocorrectionTypeNo];
[emailField setAutocapitalizationType:UITextAutocapitalizationTypeNone];
[emailField setKeyboardType:UIKeyboardTypeEmailAddress];
[cell addSubview:emailField];
else if (indexPath.section == 3)
notesField = [[UITextField alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[notesField setPlaceholder:@"Any notes to add?"];
[notesField setAutocorrectionType:UITextAutocorrectionTypeNo];
[cell addSubview:notesField];
else if (indexPath.section == 4)
sendFeedback = [[UIButton alloc] initWithFrame:CGRectMake(10, 0, 300, 45)];
[sendFeedback setTitle:@"Send Feedback" forState:UIControlStateNormal];
[sendFeedback setBackgroundColor:[UIColor colorWithRed:(111/255.0f) green:(31/255.0f) blue:(68/255.0f) alpha:1.0f]];
[sendFeedback.titleLabel setFont:[UIFont fontWithName:@"MaryAnn" size:20.0]];
[sendFeedback addTarget:self action:@selector(sendFeedback:) forControlEvents:UIControlEventTouchUpInside];
[cell setBackgroundColor:[UIColor clearColor]];
[cell addSubview:sendFeedback];
return cell;
【讨论】：
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