iOS开篇——UI之UITextField

创建文本输入框

    UITextField * textField = [[UITextField alloc]initWithFrame:CGRectMake(50, 50, 250, 40)];

设置边框样式

    textField.borderStyle = UITextBorderStyleRoundedRect;
    /*
     typedef NS_ENUM(NSInteger, UITextBorderStyle) {
     UITextBorderStyleNone, 无效果
     UITextBorderStyleLine, 线性边框 有阴影
     UITextBorderStyleBezel,
     UITextBorderStyleRoundedRect 圆角矩形
     };
     */

设置text相关

    textField.text = @"2002年的第一场雪";
    //设置字体相关
    textField.font = [UIFont systemFontOfSize:20];
    textField.textColor = [UIColor greenColor];
    //设置自适应
    textField.adjustsFontSizeToFitWidth = YES;
    //设置居中
//    textField.textAlignment = NSTextAlignmentCenter;

设置提示语

    //设置提示语
    textField.placeholder = @"请输入";
    
    //设置是否清除 开始编辑时
//    textField.clearsOnBeginEditing = YES;

设置/取消第一响应者

    //点击输入框 让输入框成为了第一响应者
    //所谓第一响应者  就是即将编辑的控件  要操作触摸的控件
    [textField becomeFirstResponder];
    //取消成为第一响应者
    [textField resignFirstResponder];

交互是否开启

    //取消交互是否开启
    textField.userInteractionEnabled = YES;

设置清除按钮

    //设置清除按钮
    textField.clearButtonMode = UITextFieldViewModeAlways;
    /*
     typedef NS_ENUM(NSInteger, UITextFieldViewMode) {
     UITextFieldViewModeNever,  从不
     UITextFieldViewModeWhileEditing,  编辑时
     UITextFieldViewModeUnlessEditing,  不编辑时显示
     UITextFieldViewModeAlways  一直显示
     };
     */

设置左右两侧view

    //**********同一个view不能同时设置为左右图片
//    左侧view
    UIView * view = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 30, 30)];
    view.backgroundColor = [UIColor blueColor];
    textField.leftView = view;
    textField.leftViewMode = UITextFieldViewModeAlways;
//    右侧view
    UIView * view1 = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 30, 30)];
    textField.rightView = view1;
    view1.backgroundColor = [UIColor greenColor];
//    textField.rightViewMode = UITextFieldViewModeAlways ;

设置键盘样式

//设置键盘样式
    textField.keyboardType = UIKeyboardTypeDefault;
    /*
     typedef NS_ENUM(NSInteger, UIKeyboardType) {
     UIKeyboardTypeDefault,                // Default type for the current input method.
     UIKeyboardTypeASCIICapable,           // Displays a keyboard which can enter ASCII characters, non-ASCII keyboards remain active
     UIKeyboardTypeNumbersAndPunctuation,  // Numbers and assorted punctuation.
     UIKeyboardTypeURL,                    // A type optimized for URL entry (shows . / .com prominently).
     UIKeyboardTypeNumberPad,              // A number pad (0-9). Suitable for PIN entry.
     UIKeyboardTypePhonePad,               // A phone pad (1-9, *, 0, #, with letters under the numbers).
     UIKeyboardTypeNamePhonePad,           // A type optimized for entering a person's name or phone number.
     UIKeyboardTypeEmailAddress,           // A type optimized for multiple email address entry (shows space @ . prominently).
     UIKeyboardTypeDecimalPad NS_ENUM_AVAILABLE_IOS(4_1),   // A number pad with a decimal point.
     UIKeyboardTypeTwitter NS_ENUM_AVAILABLE_IOS(5_0),      // A type optimized for twitter text entry (easy access to @ #)
     UIKeyboardTypeWebSearch NS_ENUM_AVAILABLE_IOS(7_0),    // A default keyboard type with URL-oriented addition (shows space . prominently).
     
     UIKeyboardTypeAlphabet = UIKeyboardTypeASCIICapable, // Deprecated
     
     };
     */
    textField.returnKeyType =UIReturnKeyDone;
    /*
     typedef NS_ENUM(NSInteger, UIReturnKeyType) {
     UIReturnKeyDefault,
     UIReturnKeyGo,
     UIReturnKeyGoogle,
     UIReturnKeyJoin,
     UIReturnKeyNext,
     UIReturnKeyRoute,
     UIReturnKeySearch,
     UIReturnKeySend,
     UIReturnKeyYahoo,
     UIReturnKeyDone,
     UIReturnKeyEmergencyCall,
     UIReturnKeyContinue NS_ENUM_AVAILABLE_IOS(9_0),
     };
     */

触摸屏幕  取消第一响应者 退出编辑

//触摸屏幕 调用此方法
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    UITextField * textField = (id)[self.view viewWithTag:1];
    [textField resignFirstResponder];
//    [self.view becomeFirstResponder];
}

实现UITextFieldDelegate代理方法

#pragma mark - UITextFieldDelegate

//是否可以开始编辑
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField{
    return YES;
}// return NO to disallow editing.

//已经开始编辑
- (void)textFieldDidBeginEditing:(UITextField *)textField{
    NSLog(@"已经开始编辑");
}// became first responder

//是否可以结束编辑 yes可以  no不可以
- (BOOL)textFieldShouldEndEditing:(UITextField *)textField{
    return YES;
}// return YES to allow editing to stop and to resign first responder status. NO to disallow the editing session to end

//已经结束编辑
- (void)textFieldDidEndEditing:(UITextField *)textField{
    //可在此进行保存草稿
    NSLog(@"已经结束编辑");
}// may be called if forced even if shouldEndEditing returns NO (e.g. view removed from window) or endEditing:YES called


- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{
    return YES;
}// return NO to not change text

//触发此方法 返回可否清除
- (BOOL)textFieldShouldClear:(UITextField *)textField{
    return NO;
}// called when clear button pressed. return NO to ignore (no notifications)

- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    
}
//点击键盘上的return 执行此方法
- (BOOL)textFieldShouldReturn:(UITextField *)textField{
    return  YES;
}// called when 'return' key pressed. return NO to ignore.