Question

你好我在这里搜索了很多关于使用shouldChangeCharactersInRange子类化uitextfield来处理最大长度的帖子。

尝试了以下线程，但仍无效： - How properly subclass UITextField in iOS? - UITextField shouldChangeCharactersInRange Delegate not working - Set custom UITextField max length

我的代码如下所示。

·H

//UITextFieldGeneral.h

#import <UIKit/UIKit.h>

@interface UITextFieldGeneral : UITextField <UITextFieldDelegate>{
    int maxLength;
}

-(void)inisialisasi:(int)maxValue;

@end

的.m

//UITextFieldGeneral.m
#import "UITextFieldGeneral.h"

@implementation UITextFieldGeneral

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
//        self.delegate = self;
    }
    return self;
}

-(void)inisialisasi:(int)maxValue{
//    self.keyboardType = UIKeyboardTypeDecimalPad;
    self.textColor = [UIColor blackColor];
    self.font = [UIFont fontWithName:fontname size:fontSizeH3];
    self.tintColor = [UIColor blackColor];
    [self setBackgroundColor:[UIColor whiteColor]];
    [self setBorderStyle:UITextBorderStyleRoundedRect];
    [self setTextAlignment:NSTextAlignmentRight];

    maxLength = maxValue;


}


- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range
replacementString:(NSString*)string{

    if (range.location >= maxLength)
        return NO;
    return YES;
}

viewcontroller中的代码

·H

@interface TransferInternDaftarRekViewController : TableViewControllerCustomForInput<UITextFieldDelegate>{

的.m

tfBerita = [[UITextFieldGeneral alloc] initWithFrame:(CGRect){xLbl+widthLbl+20,5,widthLbl,30}]; 
        tfBerita.keyboardType = UIKeyboardTypeDefault;
        [tfBerita inisialisasi:20];
        //tfBerita.delegate = tfBerita;
tfBerita.delegate = self;

不会调用theChangeCharactersInRange方法，但是如果我改变了tfBerita.delegate = self; to tfBerita.delegate = tfBerita;输入3个字符后给我一个错误。

我错过了什么吗？

使用shouldChangeCharactersInRange对uitextfield进行子类化以处理最大长度不起作用

0 个答案: