您的单元格将显示重复的文本字段值,因为您正在重用它们,而不是在单元格现在应该代表不同的对象时调整单元格详细信息。
如果您不想要这种行为(显然您不想要),那么您需要在数据源上设置单元格详细信息。然后在 cellForRowAtIndexPath() 中使用相应的对象详细信息填充当前单元格。或者,我不建议,您可以在 cellForRowAtIndexPath() 中为您添加的每个项目分配一个新单元格。当您的单元格在屏幕上不可见时,这会不必要地占用更多内存。
这是一个例子: 这只是为了演示从数据源动态填充单元格,其他一切都不是建议。
#import "PeopleTableViewController.h"
//--- Person Class
@interface Person : NSObject<UITextFieldDelegate>
@property (nonatomic, strong) NSString *name;
@property (nonatomic, strong) NSString *surname;
@end
@implementation Person
@end
//---
#define CELL_HEIGHT 80.0f
#define TEXTFIELD_HEIGHT 30.0f
#define TEXTFIELD_WIDTH 120.0f
#define TEXT_FIELD_VERTICAL_MARGIN (CELL_HEIGHT - (TEXTFIELD_HEIGHT*2)) / 3
#define TEXT_FIELD_LEFT_MARGIN 20.0f
//--- Person Cell
@class PersonCell;
@protocol PersonCellTextFieldProtocol <NSObject>
-(void)personCell: (PersonCell*)cell nameTextfieldDidChange: (NSString*)newText;
-(void)personCell: (PersonCell*)cell surnameTextfieldDidChange: (NSString*)newText;
@end
@interface PersonCell : UITableViewCell<UITextFieldDelegate>
@property (nonatomic, strong) UITextField *nameTextField;
@property (nonatomic, strong) UITextField *surnameTextField;
@property (nonatomic, strong) UILabel *positionLabel;
@property (nonatomic, assign) id<PersonCellTextFieldProtocol> delegate;
@end
@implementation PersonCell
-(instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if(self)
[self setupSubviews];
return self;
}
-(void)setupSubviews
{
NSUInteger nameTextFieldYPosition = TEXT_FIELD_VERTICAL_MARGIN;
self.nameTextField = [[UITextField alloc] initWithFrame: CGRectMake(TEXT_FIELD_LEFT_MARGIN, nameTextFieldYPosition, TEXTFIELD_WIDTH, TEXTFIELD_HEIGHT)];
self.nameTextField.borderStyle = UITextBorderStyleRoundedRect;
self.nameTextField.placeholder = @"Name";
self.nameTextField.delegate = self;
[self.nameTextField addTarget:self action:@selector(nameTextFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
[self.contentView addSubview: self.nameTextField];
self.surnameTextField = [[UITextField alloc] initWithFrame: CGRectMake(TEXT_FIELD_LEFT_MARGIN, CGRectGetMaxY(self.nameTextField.frame) + TEXT_FIELD_VERTICAL_MARGIN, TEXTFIELD_WIDTH, TEXTFIELD_HEIGHT)];
self.surnameTextField.borderStyle = UITextBorderStyleRoundedRect;
self.surnameTextField.placeholder = @"Surname";
self.surnameTextField.delegate = self;
[self.surnameTextField addTarget:self action:@selector(surnameTextFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
[self.contentView addSubview: self.surnameTextField];
self.positionLabel = [[UILabel alloc] initWithFrame: CGRectMake(5, 0, 10, 20)];
self.positionLabel.font = [UIFont systemFontOfSize: 10];
[self.contentView addSubview: self.positionLabel];
self.positionLabel.center = CGPointMake(self.positionLabel.center.x, self.contentView.center.y);
}
-(void)layoutSubviews
{
self.positionLabel.center = CGPointMake(self.positionLabel.center.x, self.contentView.center.y);
}
-(void)nameTextFieldDidChange:(UITextField*)textField
{
if([self.delegate respondsToSelector: @selector(personCell:nameTextfieldDidChange:)])
[self.delegate personCell:self nameTextfieldDidChange:textField.text];
}
-(void)surnameTextFieldDidChange:(UITextField*)textField
{
if([self.delegate respondsToSelector: @selector(personCell:surnameTextfieldDidChange:)])
[self.delegate personCell:self surnameTextfieldDidChange:textField.text];
}
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
return YES;
}
@end
//---
@interface PeopleTableViewController ()<PersonCellTextFieldProtocol>
@end
@implementation PeopleTableViewController
{
NSMutableArray *_peopleArray;
}
-(void)viewDidLoad
{
_peopleArray = [[NSMutableArray alloc] init];
[self.tableView reloadData];
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
PersonCell *cell = nil;
cell = [tableView dequeueReusableCellWithIdentifier: @"CellWithNameAndSurname"];
if(!cell)
{
cell = [[PersonCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"CellWithNameAndSurname"];
cell.contentView.backgroundColor = [[UIColor blueColor] colorWithAlphaComponent: 0.08f];
cell.delegate = self;
}
//this should be outside the above if statement!
Person *respectivePerson = _peopleArray[indexPath.row];
cell.nameTextField.text = respectivePerson.name;
cell.surnameTextField.text = respectivePerson.surname;
cell.positionLabel.text = [NSString stringWithFormat:@"%i", (int)indexPath.row];
return cell;
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return CELL_HEIGHT;
}
-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return _peopleArray.count;
}
-(void)personCell:(PersonCell *)cell nameTextfieldDidChange:(NSString *)newText
{
Person *respectivePerson = _peopleArray[[self.tableView indexPathForCell: cell].row];
respectivePerson.name = newText;
}
-(void)personCell:(PersonCell *)cell surnameTextfieldDidChange:(NSString *)newText
{
Person *respectivePerson = _peopleArray[[self.tableView indexPathForCell: cell].row];
respectivePerson.surname = newText;
}
- (IBAction)addItemBtnClick:(id)sender
{
Person *newPerson = [Person new];
[_peopleArray addObject: newPerson];
[self.tableView reloadData];
}
@end
当我点击添加时,我滚动时得到下表,没有任何重复: