自定义UITableViewCell prepareForReuse不按预期方式工作

我的prepareForReuse工作不正常。 我有一个UITableView应该有一个login UIButton在表的第一部分的第一行只。 但是，在prepareForReuse ，当我删除loginbutton时，它保持并进入下一批的行。 （video来说明 – > http://pixori.al/8g3v ）

这是我的自定义UITableViewCell ：

 #import "MAGradeCell.h" @implementation MAGradeCell - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier cellForRowAtIndexPath:(NSIndexPath *)indexPath { self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]; if (self) { // Initialization code } return self; } -(void)layoutSubviews{ [super layoutSubviews]; } - (void)prepareForReuse { self.loginButton = nil; [self removeFromSuperview]; [self.loginButton removeFromSuperview]; self.textLabel.text = nil; [super prepareForReuse]; } /* - (void)setSelected:(BOOL)selected animated:(BOOL)animated { [super setSelected:selected animated:animated]; // Configure the view for the selected state }*/ @end 

和我的viewcontroller的部分设置单元格（ cellForRowAtIndexPath ）。 即我把QBFlatButton和一切：

 - (MAGradeCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"CellIdentifier"; //UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; MAGradeCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; // // Redefine layout variables in method from `viewDidLoad` CGFloat inset = 20; // For padding if (! cell) { cell = [[MAGradeCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier cellForRowAtIndexPath:indexPath]; } // Sets up attributes of each cell cell.selectionStyle = UITableViewCellSelectionStyleNone; cell.backgroundColor = [UIColor colorWithWhite:0 alpha:0.2]; cell.textLabel.textColor = [UIColor whiteColor]; cell.detailTextLabel.textColor = [UIColor whiteColor]; QBFlatButton* loginButton = nil; if (indexPath.section == 0) { if (indexPath.row == 0) { [self configureHeaderCell:cell title:@"Grades"]; UIView *cellView = cell.contentView; loginButton = [[QBFlatButton alloc] initWithFrame:CGRectMake((cellView.frame.size.width - (80 + inset)), 18, 80, (cellView.frame.size.height -(cellView.frame.size.height/2)))]; [loginButton addTarget:self action:@selector(loginButtonWasPressed)forControlEvents:UIControlEventTouchUpInside]; loginButton.faceColor = [UIColor grayColor]; loginButton.sideColor = [UIColor clearColor]; loginButton.radius = 6.0; loginButton.margin = 4.0; loginButton.depth = 3.0; loginButton.alpha = 0.3; loginButton.titleLabel.font = [UIFont fontWithName:@"HelveticaNeue-Light" size:20]; [loginButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [loginButton setTitle:@"Login" forState:UIControlStateNormal]; [cellView addSubview:loginButton]; } else { cell.selectionStyle = UITableViewCellSelectionStyleBlue; MAGradeClient *grade = [[MAGradeClient alloc] init]; [self configureGradesCell:cell grade:grade]; } } else if (indexPath.section == 1) { if (indexPath.row == 0) { [self configureHeaderCell:cell title:@"Hourly Forecast"]; } else { // Get hourly weather and configure using method MACondition *weather = [MAManager sharedManager].hourlyForecast[indexPath.row - 1]; [self configureHourlyCell:cell weather:weather]; } } else if (indexPath.section == 2) { if (indexPath.row == 0) { [self configureHeaderCell:cell title:@"Daily Forecast"]; } else if (indexPath.section == 2) { // Get daily weather and configure using method MACondition *weather = [MAManager sharedManager].dailyForecast[indexPath.row - 1]; [self configureDailyCell:cell weather:weather]; } } return cell; } 

Answer 1

如果你这样做：

 self.loginButton = nil; 

然后尝试做：

 [self.loginButton removeFromSuperview]; 

它不会工作，因为你已经没有参考。

考虑为这个单元格使用不同的单元格标识符，因为如果你正在添加和删除一个button，它不是一个纯粹的重用。 考虑也只是隐藏/显示button。 如果你想删除它，然后将代码更改为：

 - (void)prepareForReuse { [self.loginButton removeFromSuperview]; self.loginButton = nil; self.textLabel.text = nil; [super prepareForReuse]; } 

它也看起来像你从来没有设置：

 cell.loginButton = loginButton; 

所以单元格可能没有任何使用的参考…