OC内容输入篇（四）对比UITextField和UITextView

对比UITextField和UITextView

类继承关系

- NSObject
    - UIResponder
        - UIView
            - UIControl
                - UITextField
            - UIScrollView
                - UITextView

代理方法

一

• UITextField:
  • 没有输入内容发生变化的代理方法，需要监听通知UITextFieldTextDidChangeNotification
  • 有return的代理方法:
    • - (BOOL)textFieldShouldReturn:(UITextField *)textField;
• UITextView:

  • 输入内容发生变化的代理方法

    • - (void)textViewDidChange:(UITextView *)textView;

  • 没有return的代理方法，需要自己处理

    - (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
        if ([text isEqualToString:@"\n"]) {
            [textView resignFirstResponder];
            return NO;
        }
        return YES;
    }
    

---

二、下面的这些是UITextView有但是UITextField没有的代理方法

主要集中在：

• 选中的内容变化
• URL的处理
• Attachment的处理

// 输入了内容的：这个是`UITextField`没有的，需要使用通知处理
- (void)textViewDidChange:(UITextView *)textView;
// 选中的内容改变：这个是`UITextField`没有的
- (void)textViewDidChangeSelection:(UITextView *)textView;
// 链接 url 的处理：这个是`UITextField`没有的
- (BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange interaction:(UITextItemInteraction)interaction NS_AVAILABLE_IOS(10_0);
// Attachment 的处理：这个是`UITextField`没有的
- (BOOL)textView:(UITextView *)textView shouldInteractWithTextAttachment:(NSTextAttachment *)textAttachment inRange:(NSRange)characterRange interaction:(UITextItemInteraction)interaction NS_AVAILABLE_IOS(10_0);

- (BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange NS_DEPRECATED_IOS(7_0, 10_0, "Use textView:shouldInteractWithURL:inRange:forInteractionType: instead");
- (BOOL)textView:(UITextView *)textView shouldInteractWithTextAttachment:(NSTextAttachment *)textAttachment inRange:(NSRange)characterRange NS_DEPRECATED_IOS(7_0, 10_0, "Use textView:shouldInteractWithTextAttachment:inRange:forInteractionType: instead");

三、下面的这些是UITextField有但是UITextView没有的代理方法

主要集中在:

• return键的点击
• 右侧clearButton的点击

- (BOOL)textFieldShouldClear:(UITextField *)textField;               // called when clear button pressed. return NO to ignore (no notifications)
- (BOOL)textFieldShouldReturn:(UITextField *)textField;              // called when 'return' key pressed. return NO to ignore.

相同的属性

@property(null_resettable,nonatomic,copy) NSString *text;
@property(nullable,nonatomic,strong) UIFont *font;
@property(nullable,nonatomic,strong) UIColor *textColor;
@property(nonatomic) NSTextAlignment textAlignment;    // default is NSLeftTextAlignment
@property(null_resettable,copy) NSAttributedString *attributedText NS_AVAILABLE_IOS(6_0);
@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.

---

@property(nonatomic) BOOL allowsEditingTextAttributes NS_AVAILABLE_IOS(6_0);
@property(nonatomic,copy) NSDictionary *typingAttributes NS_AVAILABLE_IOS(6_0); // automatically resets when the selection changes

• allowsEditingTextAttributes : 会有加粗bold、斜体italic、下划线underline的操作
• typingAttributes : 用来控制输入的时候，输入的文字的属性，比如斜体，下划线等等；The attributes to apply to new text being entered by the user.

不同点

UITextField有但是UITextView没有的

// 是显示的文字内容的属性，（之前可能就存在内容了）
@property(nonatomic,copy)   NSDictionary           *defaultTextAttributes NS_AVAILABLE_IOS(7_0);

// 边框样式
@property(nonatomic)        UITextBorderStyle       borderStyle;

// 占位符
@property(nullable, nonatomic,copy) NSString  *placeholder;          // default is nil. string is drawn 70% gray
@property(nullable, nonatomic,copy)   NSAttributedString  *attributedPlaceholder NS_AVAILABLE_IOS(6_0); // default is nil

// 右侧的清除按钮
@property(nonatomic) BOOL  clearsOnBeginEditing; // default is NO which moves cursor to location clicked. if YES, all text cleared
@property(nonatomic)        UITextFieldViewMode  clearButtonMode; // sets when the clear button shows up. default is UITextFieldViewModeNever

// 自动调整，因为 UITextField 只能单行输入，所以有了这个
@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

// 背景图片
@property(nullable, nonatomic,strong) UIImage                *background;           // default is nil. draw in border rect. image should be stretchable
@property(nullable, nonatomic,strong) UIImage                *disabledBackground;   // default is nil. ignored if background not set. image should be stretchable

// 正在编辑中的判断
@property(nonatomic,readonly,getter=isEditing) BOOL editing;

// 左侧/右侧 附件内容
@property(nullable, nonatomic,strong) UIView *leftView;        // e.g. magnifying glass
@property(nonatomic)        UITextFieldViewMode  leftViewMode;    // sets when the left view shows up. default is UITextFieldViewModeNever
@property(nullable, nonatomic,strong) UIView              *rightView;       // e.g. bookmarks button
@property(nonatomic)        UITextFieldViewMode  rightViewMode;   // sets when the right view shows up. default is UITextFieldViewModeNever

---

UITextView有但是UITextField没有的

// 选中的内容范围
@property(nonatomic) NSRange selectedRange;
// 是否可以选中
@property(nonatomic,getter=isSelectable) BOOL selectable NS_AVAILABLE_IOS(7_0); 

// 自动检测数据类型
@property(nonatomic) UIDataDetectorTypes dataDetectorTypes NS_AVAILABLE_IOS(3_0) __TVOS_PROHIBITED;

// 滚动到 range 范围，UITextView 是多行显示，可以滚动的
- (void)scrollRangeToVisible:(NSRange)range;

// 文字内边距，可以调整文字的输入范围
@property(nonatomic, assign) UIEdgeInsets textContainerInset NS_AVAILABLE_IOS(7_0);

// 链接url的属性设置，特殊处理
@property(null_resettable, nonatomic, copy) NSDictionary *linkTextAttributes NS_AVAILABLE_IOS(7_0);

1、选中可以通过都遵守的协议UITextInput获取
2、UITextView可以自动检测一些数据类型，比如URL

UITextView和UITextField都有，但是处理不同的

禁止编辑：

• UITextField: enabled
• UITextView: editable

小结：

• UITextField: 适合单行输入，右侧有清除按钮，安全输入
• UITextView: 适合多上输入

最后

GitHub参考链接