类支付宝微信密码输入框

代码地址如下：
http://www.demodashi.com/demo/13444.html

方框圆点密文，类支付宝微信密码输入框

一、目录结构图

二、效果图

![效果图]

三、思路

1. 创建一个UITextField，网上有的demo是用6个textfield，其实一个就够! 然后用view 添加边框 这样我们看到的就是一个有6个等同输入框的视图.

2. 创建圆点可以通过创建一个UIView，通过设置圆角使其成为一个圆了，然后让其frame 显示在边框view的中间就可以了.

3. 当点击输入时候使用shouldChangeCharactersInRange 方法来用来输入的 textfield 做处理, 默认初始化完毕就成为第一响应者。在此代理方法中处理一下键盘回调和字数限制.

4. 当密码的长度达到需要的长度时,关闭第一响应者. 通过代理来传递 password 的值.

5. 提供一个外部清空password的方法

6. 其实主要原理就是一种类似视觉欺骗的做法，底部一个看不到的textfield，然后在上边排列N个view，当有输入的时候根据输入的字数，来给view添加边框颜色，和显示中间圆点。

使用方法：

SWPasswordView *pwdinputbox = [[SWPasswordView alloc]initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width - 60, 50)];
    pwdinputbox.center = self.view.center;
    pwdinputbox.delegate = self;
    [self.view addSubview:pwdinputbox];

遵循代理 **SWPasswordViewDelegate ** 并实现方法，输入完毕回调输入字符

- (void)inputDoneWithReslutText:(NSString *)text{
    NSLog(@"输入的字符是：%@",text);
}

四、实现原理

1. 采用一个textfield，文字为白色，背景为白色，光标为白色

_textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, K_Field_Height)];
        _textField.backgroundColor = [UIColor clearColor];
        //输入的文字颜色为白色
        _textField.textColor = [UIColor whiteColor];
        //输入框光标的颜色为白色
        _textField.tintColor = [UIColor whiteColor];
        _textField.delegate = self;
        _textField.autocapitalizationType = UITextAutocapitalizationTypeNone;
        _textField.keyboardType = UIKeyboardTypeNumberPad;
        _textField.layer.borderColor = [[UIColor whiteColor] CGColor];
        _textField.layer.borderWidth = 1;
        [_textField addTarget:self action:@selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged];

2. 初始化边框view和圆点view

for (int i = 0; i < kDotCount; i++) {
        UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(i*(width+margin),0,width,K_Field_Height)];
        lineView.backgroundColor = [UIColor whiteColor];
        lineView.layer.cornerRadius = 2.0f;
        lineView.layer.borderColor = [UIColor colorWithRed:225/255.0 green:225/255.0 blue:225/255.0 alpha:1].CGColor;
        lineView.layer.borderWidth = 1.f;
        [self addSubview:lineView];
        [self.bottomArray addObject:lineView];
        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(showTextField)];
        [lineView addGestureRecognizer:tap];
        UIView *dotView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, kDotSize.width, kDotSize.height)];
        dotView.center = lineView.center;
        dotView.backgroundColor = [UIColor colorWithRed:30/255.0 green:144/255.0 blue:255/255.0 alpha:1];
        dotView.layer.cornerRadius = kDotSize.width / 2.0f;
        dotView.clipsToBounds = YES;
        dotView.hidden = YES; //先隐藏
        [self addSubview:dotView];
        //把创建的黑色点加入到数组中
        [self.dotArray addObject:dotView];
    }

3. 在输入的代理中动态显示和隐藏

 *  重置显示的点
 */
- (void)textFieldDidChange:(UITextField *)textField
{
    NSLog(@"%@", textField.text);
    for (UIView *dotView in self.dotArray) {
        dotView.hidden = YES;
    }
    for (UIView *lineView in self.bottomArray) {
        lineView.layer.borderColor = [UIColor colorWithRed:225/255.0 green:225/255.0 blue:225/255.0 alpha:1].CGColor;
    }
    for (int i = 0; i < textField.text.length; i++) {
        ((UIView *)[self.dotArray objectAtIndex:i]).hidden = NO;
        ((UIView *)[self.bottomArray objectAtIndex:i]).layer.borderColor = [UIColor colorWithRed:30/255.0 green:144/255.0 blue:255/255.0 alpha:1].CGColor;
    }
    if (textField.text.length == kDotCount) {
        NSLog(@"输入完毕");
        [textField resignFirstResponder];
        if ([self.delegate respondsToSelector:@selector(inputDoneWithReslutText:)]) {
            [self.delegate inputDoneWithReslutText:self.textField.text];
        }
    }
}
```类支付宝微信密码输入框

> 代码地址如下：<br>http://www.demodashi.com/demo/13444.html



> 注：本文著作权归作者，由demo大师代发，拒绝转载，转载需要作者授权