UITextField的使用

UITextField定义了一套代理,用来监听输入的内容

//设置默认提示文本

    self.loginTextField.placeholder = @"手机号/QQ号/邮箱";

    //设置textfield 的边框类型boardstyled

    self.loginTextField.borderStyle = UITextBorderStyleRoundedRect;

    [self.view addSubview:self.loginTextField];

    //更改键盘下方的return的类型

    self.loginTextField.returnKeyType = UIReturnKeyGoogle;

    //设置键盘的类型

    self.loginTextField.keyboardType = UIKeyboardTypeURL;

    //设置delegate = self(当textfield的状态变了,当前这个类来接收回调方法)

    self.loginTextField.delegate = self;

    

    //设置左边的放大镜视图

    UIImage *searchImage = [UIImage imageNamed:@"search"];

    UIImageView *searchImageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 30, 30)];

    searchImageView.image = searchImage;

    

    self.loginTextField.leftView = searchImageView;

    self.loginTextField.leftViewMode = UITextFieldViewModeAlways ;

    

    //创建右边的下拉视图

    UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];

    btn.frame = CGRectMake(0, 0, 15, 15);

    [btn setImage:[UIImage imageNamed:@"down"] forState:UIControlStateNormal];

    btn.tag = kChoiceButtonStatusDown;

    

    [btn addTarget:self action:@selector(choiceUser:) forControlEvents:UIControlEventTouchUpInside];

    

    UIView *rView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 30, 15)];

    rView.backgroundColor = [UIColor clearColor];

    [rView addSubview:btn];

    

    self.loginTextField.rightView = rView;

    self.loginTextField.rightViewMode = UITextFieldViewModeAlways;

-(void)choiceUser:(UIButton *)sender{

    if (sender.tag == kChoiceButtonStatusDown) {

        [sender setImage:[UIImage imageNamed:@"up"] forState:UIControlStateNormal];

        sender.tag = kChoiceButtonStatusUp;

    }else{

        [sender setImage:[UIImage imageNamed:@"down"] forState:UIControlStateNormal];

        sender.tag = kChoiceButtonStatusDown;

        

    }

}

//当键盘的return键被按下了

-(BOOL)textFieldShouldReturn:(UITextField *)textField{

    //如何隐藏键盘

    //当点击某个textfield,那么这个textfiled作为第一响应者,由于是一个textfield,需要用户输入内容,系统自动弹出键盘

    //需要取消第一响应者,系统就会隐藏键盘

    [textField resignFirstResponder];

    return  YES;

}

//当用户输入过程中,每按下一个字符,都会先来调用这个方法

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

    NSLog(@"输入之前的字符%@",textField.text);

    NSLog(@"输入了一个字符:%@",string);

    NSLog(@"替换从%ld-%ld",range.location,range.length);

    return YES;

}

 

posted @ 2016-04-07 13:22  蜗牛才是大牛  阅读(177)  评论(0编辑  收藏  举报