12. UITextField

1. UITextField 的认识

UItextField通常用于外部数据输入，以实现人机交互。比如我们QQ、微信的登录界面中让你输入账号和密码的地方

2. UITextField 控件的属性设置

#import "ViewController.h"

@interface ViewController ()

{

UITextField *_textField;

}

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

self.view.backgroundColor = [UIColor blackColor];

// 创建TextField

[self creatTextField];

// TextField属性设置

[self setTextFieldPro];

// TextField文本属性设置

[self setTextOfTextFieldPro];

// TextField keyBoard设置

[self setKeyBoardOfTextField];

}

- (void)creatTextField

{

_textField = [[UITextField alloc] initWithFrame:CGRectMake(20, 100, 300, 50)];

_textField.backgroundColor = [UIColor yellowColor];

[self.view addSubview:_textField];

}

- (void)setTextFieldPro

{

// 1. 设置边框

//    UITextBorderStyleNone, 没有边框

//    UITextBorderStyleLine, 线性边框

//    UITextBorderStyleBezel, 尖角边框

//    UITextBorderStyleRoundedRect // 圆角矩形

_textField.borderStyle = UITextBorderStyleLine;

// 2. 设置图片(设置边框不能设置UITextBorderStyleRoundedRect，否则没有效果)

//    _textField.background = [UIImage imageNamed:@"11"];

// 3. 设置编辑状态(NO，用户点击没有响应)

_textField.enabled = YES;

}

- (void)setTextOfTextFieldPro

{

// 1.默认文字

//    _textField.text = @"奔跑吧，少年";

// 2. 设置字体颜色

_textField.textColor = [UIColor redColor];

// 3. 设置文字的对齐方式

//    _textField.textAlignment = NSTextAlignmentCenter;

// 4. 设置文字的大小

_textField.font = [UIFont systemFontOfSize:30];

// 5. 设置占位文字

//    _textField.placeholder = @"请输入密码";

// 6. 清除原有文字

_textField.clearsOnBeginEditing = YES;

// 让_textField成为键盘的第一响应者

[_textField becomeFirstResponder];

// 判断是不是在编辑状态

BOOL boo =  _textField.isEditing;

// 设置清除按钮什么时候显示

_textField.clearButtonMode = UITextFieldViewModeAlways;

// 设置_textField 左视图(左右视图只能显示一个)

UIImageView *leftImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 50, 50)];

leftImageView.image = [UIImage imageNamed:@"TM"];

_textField.leftView = leftImageView;

_textField.leftViewMode = UITextFieldViewModeAlways;

//    _textField.rightView = leftImageView;

//    _textField.rightViewMode = UITextFieldViewModeAlways;

// 密文显示

//    _textField.secureTextEntry = YES;

// 是否自动大小写

//    UITextAutocapitalizationTypeNone,

//    UITextAutocapitalizationTypeWords, // 单词首字母大写

//    UITextAutocapitalizationTypeSentences,// 句子首字母大写

//    UITextAutocapitalizationTypeAllCharacters // 全大写

//    _textField.autocapitalizationType = UITextAutocapitalizationTypeAllCharacters;

}

- (void)setKeyBoardOfTextField

{

// 设置键盘的颜色

_textField.keyboardAppearance = UIKeyboardAppearanceDark;

// 设置键盘的类型

// UIKeyboardTypeNumberPad 只能输入数字

_textField.keyboardType  = UIKeyboardTypeURL;

// 返回按钮的样式

_textField.returnKeyType = UIReturnKeyNext;

// 设置键盘的二级键盘

UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 50)];

imageView.image = [UIImage imageNamed:@"TM"];

_textField.inputAccessoryView = imageView;

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

// 移除第一响应者 （键盘退出）

[_textField resignFirstResponder];

NSLog(@"%@",_textField.text);

}

@end

3. UITextField 代理方法

@interface ViewController ()<UITextFieldDelegate>

{

UITextField *_textField;

}

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

[self addTextFieldToView];

}

- (void)addTextFieldToView

{

_textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 100, self.view.frame.size.width, 80)];

_textField.backgroundColor = [UIColor lightGrayColor];

_textField.font = [UIFont systemFontOfSize:40];

_textField.placeholder = @"请输入文字";

_textField.clearButtonMode = UITextFieldViewModeAlways;

// 设置代理

_textField.delegate = self;

[self.view addSubview:_textField];

}

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField

{

NSLog(@"将要编辑");

// YES 可以继续编辑 NO 不让编辑

return YES;

}

- (BOOL)textFieldShouldEndEditing:(UITextField *)textField

{

NSLog(@"---%@",textField.text);

NSLog(@"将要结束编辑的时候");

return YES;

}

- (void)textFieldDidBeginEditing:(UITextField *)textField

{

NSLog(@"已经开始编辑");

}

- (void)textFieldDidEndEditing:(UITextField *)textField

{

NSLog(@"已经结束编辑");

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

[_textField resignFirstResponder];

}

- (BOOL)textFieldShouldClear:(UITextField *)textField

{

NSLog(@"清除的时候");

// NO 不让清除  YES 让清除

return NO;

}

- (BOOL)textFieldShouldReturn:(UITextField *)textField

{

NSLog(@"点击了Return按钮的时候");

return YES;

}

#pragma mark - 用户每次输入信息的或删除的时候都调用

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

{

NSLog(@"%ld-- %@",range.length,string);

return YES;

}

@end

4. 拓展，键盘弹出遮挡主输入框处理（处理思想是让输入框在键盘弹出的时候上移，键盘退出的时候回到原来的位置）

#import "ViewController.h"

@interface ViewController ()

{

UITextField *_textField;

}

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

// 添加UITextField

[self addTextField];

// 添加检测给键盘

[self keyBaordShowOrHide];

}

- (void)addTextField

{

CGFloat textFieldX = 20;

CGFloat textFieldW = self.view.frame.size.width - 2 * textFieldX;

CGFloat textFieldH = 50;

CGFloat textFieldY = 500;

_textField = [[UITextField alloc] initWithFrame:CGRectMake(textFieldX, textFieldY, textFieldW, textFieldH)];

_textField.backgroundColor = [UIColor lightGrayColor];

[self.view addSubview:_textField];

}

- (void)keyBaordShowOrHide

{

// 检测键盘弹出

// 1. 谁去检测

// 2. 检测到键盘弹出执行什么方法

// 3. 区别消息是不是键盘弹出的消息

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(showKeyBoard:) name:UIKeyboardWillShowNotification object:nil];

//检测键盘消失

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(hideKeyBoard:) name:UIKeyboardWillHideNotification object:nil];

}

- (void)hideKeyBoard:(NSNotification *)sender

{

NSLog(@"键盘消失");// 输入框还原

// view 位置还原

self.view.transform = CGAffineTransformIdentity;

}

- (void)showKeyBoard:(NSNotification *)sender

{

NSLog(@"键盘弹起");

NSLog(@"%@",sender);

// 获取键盘的高度

CGRect rect = [[sender.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];

CGFloat keyBoardH = rect.size.height;

// 让整个屏幕往上移动一个键盘的高度

self.view.transform = CGAffineTransformMakeTranslation(0, - keyBoardH + 100);

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

[_textField resignFirstResponder];

}

@end