UITextField.h

//
//  UITextField.h
//  UIKit
//
//  Copyright (c) 2005-2013, Apple Inc. All rights reserved.
//


@class UIImage, UIImageView, UILabel, UIColor, UIButton;
@class UITextFieldAtomBackgroundView;
@class UITextFieldBackgroundView;
@class UITextFieldBorderView;
@class UITextFieldLabel;
@class UITextInputTraits;
@class UITextSelectionView;
@class UITextInteractionAssistant;
@class UIPopoverController;
@protocol UITextFieldDelegate;
@protocol UITextSelecting;

typedef NS_ENUM(NSInteger, UITextBorderStyle) {
    UITextBorderStyleNone,
    UITextBorderStyleLine,
    UITextBorderStyleBezel,
    UITextBorderStyleRoundedRect
};

typedef NS_ENUM(NSInteger, UITextFieldViewMode) {
    UITextFieldViewModeNever,            // 一直不显示
    UITextFieldViewModeWhileEditing,     // 编辑是显示
    UITextFieldViewModeUnlessEditing,    // 不编辑时显示
    UITextFieldViewModeAlways            // 一直显示
};

NS_CLASS_AVAILABLE_IOS(2_0) @interface UITextField : UIControl  

@property(nonatomic,copy)   NSString               *text;                 // 显示的文字
@property(nonatomic,copy)   NSAttributedString     *attributedText NS_AVAILABLE_IOS(6_0); // 带文本信息的文字
@property(nonatomic,retain) UIColor                *textColor;            // 文字颜色
@property(nonatomic,retain) UIFont                 *font;                 // 字体
@property(nonatomic)        NSTextAlignment         textAlignment;        // 对齐方式，默认左对齐
@property(nonatomic)        UITextBorderStyle       borderStyle;          //
@property(nonatomic,copy)   NSDictionary           *defaultTextAttributes NS_AVAILABLE_IOS(7_0); //
@property(nonatomic,copy)   NSString               *placeholder;          // default is nil. string is drawn 70% gray
@property(nonatomic,copy)   NSAttributedString     *attributedPlaceholder NS_AVAILABLE_IOS(6_0); // default is nil
@property(nonatomic)        BOOL                    clearsOnBeginEditing; // default is NO which moves cursor to location clicked. if YES, all text cleared
@property(nonatomic)        BOOL                    adjustsFontSizeToFitWidth; // default is NO. if YES, text will shrink to minFontSize along baseline
@property(nonatomic)        CGFloat                 minimumFontSize;      // default is 0.0. actual min may be pinned to something readable. used if adjustsFontSizeToFitWidth is YES
@property(nonatomic,assign) id delegate;             // default is nil. weak reference
@property(nonatomic,retain) UIImage                *background;           // default is nil. draw in border rect. image should be stretchable
@property(nonatomic,retain) UIImage                *disabledBackground;   // default is nil. ignored if background not set. image should be stretchable

@property(nonatomic,readonly,getter=isEditing) BOOL editing;
@property(nonatomic) BOOL allowsEditingTextAttributes NS_AVAILABLE_IOS(6_0); // default is NO. allows editing text attributes with style operations and pasting rich text
@property(nonatomic,copy) NSDictionary *typingAttributes NS_AVAILABLE_IOS(6_0); // automatically resets when the selection changes


@property(nonatomic)        UITextFieldViewMode  clearButtonMode; // sets when the clear button shows up. default is UITextFieldViewModeNever

@property(nonatomic,retain) UIView              *leftView;        // 文本框左边显示的view e.g. magnifying glass
@property(nonatomic)        UITextFieldViewMode  leftViewMode;    // sets when the left view shows up. default is UITextFieldViewModeNever

@property(nonatomic,retain) UIView              *rightView;       // 文本框右边显示的viewe.g. bookmarks button
@property(nonatomic)        UITextFieldViewMode  rightViewMode;   // sets when the right view shows up. default is UITextFieldViewModeNever

// drawing and positioning overrides

- (CGRect)borderRectForBounds:(CGRect)bounds;
- (CGRect)textRectForBounds:(CGRect)bounds;
- (CGRect)placeholderRectForBounds:(CGRect)bounds;
- (CGRect)editingRectForBounds:(CGRect)bounds;
- (CGRect)clearButtonRectForBounds:(CGRect)bounds;
- (CGRect)leftViewRectForBounds:(CGRect)bounds;
- (CGRect)rightViewRectForBounds:(CGRect)bounds;

- (void)drawTextInRect:(CGRect)rect;
- (void)drawPlaceholderInRect:(CGRect)rect;

@property (readwrite, retain) UIView *inputView;
@property (readwrite, retain) UIView *inputAccessoryView;

@property(nonatomic) BOOL clearsOnInsertion NS_AVAILABLE_IOS(6_0); // defaults to NO. if YES, the selection UI is hidden, and inserting text will replace the contents of the field. changing the selection will automatically set this to NO.

@end

@interface UIView (UITextField)
// 结束编辑，退出键盘
- (BOOL)endEditing:(BOOL)force;
@end

#pragma - mark - 代理协议
@protocol UITextFieldDelegate 

@optional

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField;        // return NO to disallow editing.
# 键盘一弹出就调用这个方法，开始编辑
- (void)textFieldDidBeginEditing:(UITextField *)textField;           // became first responder
- (BOOL)textFieldShouldEndEditing:(UITextField *)textField;          // return YES to allow editing to stop and to resign first responder status. NO to disallow the editing session to end
- (void)textFieldDidEndEditing:(UITextField *)textField;             // 结束编辑，是否要退出键盘

// 文本框能不能输入文本，返回NO则不能输入
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string;   

// 点击清除按钮时调用（文本框中的清除按钮）
- (BOOL)textFieldShouldClear:(UITextField *)textField;
// 点击return按钮调用
- (BOOL)textFieldShouldReturn:(UITextField *)textField;

@end

// 通知消息
UIKIT_EXTERN NSString *const UITextFieldTextDidBeginEditingNotification; // 开始编辑
UIKIT_EXTERN NSString *const UITextFieldTextDidEndEditingNotification;   // 结束编辑
UIKIT_EXTERN NSString *const UITextFieldTextDidChangeNotification;       // 输入框文字改变