(Swift&OC)UITextView的的使用技巧

一、关键词

• 1.1.弹性方向

  alwaysBounceVertical垂直
  alwaysBounceHorizontal 水平

• 1.2.滑动UITextView键盘下去
  keyboardDismissMode = UIScrollViewKeyboardDismissMode.onDrag

• 1.3.输入框是否有内容

  hasText : 状态是true 和 false

• 1.4. UITextView上面添加view

  inputAccessoryView

• 1.5. 自定义键盘

  inputView

• 1.6.有关键盘的通知(设置动画节奏),建议多看看下面的代码注释

  • UIView动画的本质是核心动画, 所以可以给核心动画设置动画节奏

二、Swift中的使用

• 2.1.键盘上加一个view(JKTextViewController)

  import UIKit
  
  class JKTextViewController: UIViewController {
  
  override func viewDidLoad() {
    super.viewDidLoad()
    
    /**
        1.控制器的基本设置
     */
    title = "JKTextView"
    view.backgroundColor = UIColor.white
    self.edgesForExtendedLayout = []
    
    /**
        2.添加UITextView和提示内容以及键盘上的view
     */
    view.addSubview(textView)
    textView.addSubview(placeholderLabel)
    textView.inputAccessoryView = jkInputAccessoryView
  }
  
  // MARK: UITextView 的创建
  private lazy var textView:UITextView = {
    
    let textview = UITextView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height-64))
    textview.font = UIFont.systemFont(ofSize: 20)
    // 垂直水平方向有弹性
    textview.alwaysBounceVertical = true
    // 垂直方向滑动键盘下去
    textview.keyboardDismissMode = UIScrollViewKeyboardDismissMode.onDrag
    return textview
  }()
  
  // MARK: UILabel 提示文本
  private lazy var placeholderLabel: UILabel = {
    
    let label = UILabel(frame: CGRect(x: 5, y: 9, width: UIScreen.main.bounds.width-10, height: 22))
    label.font = UIFont .systemFont(ofSize: 20)
    label.textColor = UIColor.red
    label.text = "分享新鲜事"
    return label
    
  }()
  
   // MARK: UIView 键盘上加个view
   private lazy var jkInputAccessoryView: UIView = {
    
     let inputView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 44))
     inputView.backgroundColor = UIColor.green
     return inputView
    
   }()
  }
  
  // MARK: UITextView代理的实现
   extension JKTextViewController: UITextViewDelegate{
  
   func textViewDidChange(_ textView: UITextView) {
    
     /**
         hasText 可以判断UITextView是否有内容
      */
     placeholderLabel.isHidden = textView.hasText
  
     }
   }
  

• 2.2.切换自定义键盘(JKTextViewController)

  import UIKit
  
  class JKTextViewController: UIViewController {
  
  override func viewDidLoad() {
    super.viewDidLoad()
    
    // 0.注册通知监听键盘弹出和消失
    NotificationCenter.default.addObserver(self, selector: #selector(JKTextViewController.keyboardChange), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
    
    /**
        1.控制器的基本设置
     */
    title = "JKTextView"
    view.backgroundColor = UIColor.white
    self.edgesForExtendedLayout = []
    
    /**
        2.添加UITextView和提示内容以及键盘上的view
     */
    view.addSubview(textView)
    textView.addSubview(placeholderLabel)
    /**
        3.输入框上面自定义一个view
     */
    view.addSubview(toolBar)
    toolBar.addSubview(toolBarBtn)
    
  }
  
   /**
       只要键盘改变就会调用
    */
   @objc func keyboardChange(notify: NSNotification)
   {
    // 1.取出键盘最终的rect
    let value = notify.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue
    let rect = value.cgRectValue
    
    // 2.修改工具条的约束
    // 弹出 : Y = 409 height = 258
    // 关闭 : Y = 667 height = 258
    // 667 - 409 = 258
    // 667 - 667 = 0
    
    let duration = notify.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! NSNumber
    /*
     工具条回弹是因为执行了两次动画, 而系统自带的键盘的动画节奏(曲线) 7
     7在apple API中并没有提供给我们, 但是我们可以使用
     7这种节奏有一个特点: 如果连续执行两次动画, 不管上一次有没有执行完毕, 都会立刻执行下一次
     也就是说上一次可能会被忽略
     
     如果将动画节奏设置为7, 那么动画的时长无论如何都会自动修改为0.5
     
     UIView动画的本质是核心动画, 所以可以给核心动画设置动画节奏
     */
    // 1.取出键盘的动画节奏
    let curve = notify.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! NSNumber
    
    UIView.animate(withDuration: duration.doubleValue) { () -> Void in
        
        // 2.设置动画节奏
        UIView.setAnimationCurve(UIViewAnimationCurve(rawValue: curve.intValue)!)
        self.toolBar.frame.origin.y = rect.origin.y - 64 - 44
    }
    
    let anim = toolBar.layer.animation(forKey: "position")
    print("duration = \(String(describing: anim?.duration))")
  }
  
  // MARK: 切换键盘
  @objc func switchKeyBoard() {
    
    print("切换表情键盘")
    print(#function)
    // 结论: 如果是系统自带的键盘, 那么inputView = nil
    //      如果不是系统自带的键盘, 那么inputView != nil
    //        print(textView.inputView)
    
    // 1.关闭键盘
    textView.resignFirstResponder()
    
    // 2.设置inputView
    textView.inputView = (textView.inputView == nil) ? keyBoardView : nil
    
    // 3.从新召唤出键盘
    textView.becomeFirstResponder()
  }
  
   deinit
   {
     NotificationCenter.default.removeObserver(self)
   }
  
   // MARK: UITextView 的创建
   private lazy var textView:UITextView = {
    
    let textview = UITextView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height-64))
    textview.font = UIFont.systemFont(ofSize: 20)
    // 垂直水平方向有弹性
    textview.alwaysBounceVertical = true
    // 垂直方向滑动键盘下去
    textview.keyboardDismissMode = UIScrollViewKeyboardDismissMode.onDrag
    return textview
   }()
  
   // MARK: UILabel 提示文本
   private lazy var placeholderLabel: UILabel = {
    
    let label = UILabel(frame: CGRect(x: 5, y: 9, width: UIScreen.main.bounds.width-10, height: 22))
    label.font = UIFont .systemFont(ofSize: 20)
    label.textColor = UIColor.red
    label.text = "分享新鲜事"
    return label
    
   }()
  
   // MARK: UIView 键盘上加个view
   private lazy var toolBar: UIView = {
    
    let inputView = UIView(frame: CGRect(x: 0, y: UIScreen.main.bounds.height-64-44, width: UIScreen.main.bounds.width, height: 44))
    inputView.backgroundColor = UIColor.green
    return inputView
    
   }()
  
   // MARK: UIView 键盘上加个view 上面加个button
   private lazy var toolBarBtn: UIButton = {
    
    let btn = UIButton(frame: CGRect(x: UIScreen.main.bounds.width-150, y: 0, width: 100, height: 44))
    btn.backgroundColor = UIColor.purple
    btn.titleLabel?.font = UIFont.systemFont(ofSize: 16)
    btn.setTitle("切换键盘", for: UIControlState.normal)
    btn.addTarget(self, action: #selector(JKTextViewController.switchKeyBoard), for: UIControlEvents.touchUpInside)
    return btn
    
   }()
  
   // MARK: 自定义键盘
   private lazy var keyBoardView: UIView = {
    
    let keyboardView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 100))
    keyboardView.backgroundColor = UIColor.brown
    return keyboardView
    
    }()
  }
  
  // MARK: UITextView代理的实现
  extension JKTextViewController: UITextViewDelegate{
  
    func textViewDidChange(_ textView: UITextView) {
      /**
          hasText 可以判断UITextView是否有内容
       */
       placeholderLabel.isHidden = textView.hasText
    }
  }
  

三、OC中的使用

• 3.1.键盘上加一个view(TestViewController)

  #import "TestViewController.h"
  #define CIO_SCREEN_WIDTH [UIScreen mainScreen].bounds.size.width
  #define CIO_SCREEN_HEIGHT [UIScreen mainScreen].bounds.size.height
  #define TitleBlackCOLOR [UIColor colorWithRed:(51)/255.0 green:(51)/255.0 blue:(51)/255.0 alpha:1]
  #define backGayCOLOR [UIColor colorWithRed:(232)/255.0 green:(232)/255.0 blue:(232)/255.0 alpha:1]
  @interface TestViewController ()
  
  /**
     UITextView输入框的创建
   */
  @property(nonatomic,strong) UITextView *jkTextView;
  /**
   提示内容
  */
  @property(nonatomic,strong) UILabel *placeholderLabel;
  /**
    键盘上添加一个view
   */
  @property(nonatomic,strong) UIView *jkInputAccessoryView;
  
  @end
  
  @implementation TestViewController
  
  - (void)viewDidLoad {
     [super viewDidLoad];
  
     self.edgesForExtendedLayout = UIRectEdgeNone;
     self.view.backgroundColor = [UIColor whiteColor];
  
     [self.view addSubview:self.jkTextView];
     [self.jkTextView addSubview:self.placeholderLabel];
     self.jkTextView.inputAccessoryView = self.jkInputAccessoryView;
  
  }
  
  #pragma mark  textview的变化
  -(void)textViewDidChange:(UITextView *)textView{
  
     self.placeholderLabel.hidden = textView.hasText;
  }
  
  -(UITextView *)jkTextView{
  
    if (!_jkTextView) {
  
      _jkTextView = [[UITextView alloc]initWithFrame:CGRectMake(0, 0, CIO_SCREEN_WIDTH,CIO_SCREEN_HEIGHT-64)];
      [_jkTextView becomeFirstResponder];
      // UITextView可以垂直滑动弹出键盘
      _jkTextView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
      _jkTextView.alwaysBounceVertical = YES;
      _jkTextView.delegate = self;
      _jkTextView.backgroundColor = [UIColor whiteColor];
      _jkTextView.textColor = TitleBlackCOLOR;
      _jkTextView.font = [UIFont systemFontOfSize:16.f];
     }
    return _jkTextView;
  }
  
  -(UILabel *)placeholderLabel{
  
      if (!_placeholderLabel) {
  
         _placeholderLabel = [[UILabel alloc]initWithFrame:CGRectMake(5, 9, CIO_SCREEN_WIDTH-10, 22)];
         _placeholderLabel.text = @"分享新鲜事";
         _placeholderLabel.textColor = backGayCOLOR;
         _placeholderLabel.font = [UIFont systemFontOfSize:20];
       }
  
    return _placeholderLabel;
  }
  
  -(UIView *)jkInputAccessoryView{
  
     if (!_jkInputAccessoryView) {
  
        _jkInputAccessoryView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, CIO_SCREEN_WIDTH, 44)];
        _jkInputAccessoryView.backgroundColor = [UIColor redColor];
      }
     return _jkInputAccessoryView;
   }
  
  @end
  

• 3.2.切换自定义键盘(TestViewController)

  #import "TestViewController.h"
  #import "UIView+JKUiviewExtension.h"
  
  #define CIO_SCREEN_WIDTH [UIScreen mainScreen].bounds.size.width
  #define CIO_SCREEN_HEIGHT [UIScreen mainScreen].bounds.size.height
  #define TitleBlackCOLOR [UIColor colorWithRed:(51)/255.0 green:(51)/255.0 blue:(51)/255.0 alpha:1]
  #define backGayCOLOR [UIColor colorWithRed:(232)/255.0 green:(232)/255.0 blue:(232)/255.0 alpha:1]
  
  @interface TestViewController ()
  
   /**
       UITextView输入框的创建
     */
     @property(nonatomic,strong) UITextView *jkTextView;
     /**
        提示内容
      */
     @property(nonatomic,strong) UILabel *placeholderLabel;
     /**
         键盘上添加一个view
      */
      @property(nonatomic,strong) UIView *tooBarView;
      @property(nonatomic,strong) UIButton *tooBarViewBtn;
  
  // 自定义键盘
  @property(nonatomic,strong) UIView *keyBoardView;
  
  @end
  
  @implementation TestViewController
  
  - (void)viewDidLoad {
    [super viewDidLoad];
  
    self.edgesForExtendedLayout = UIRectEdgeNone;
    self.view.backgroundColor = [UIColor whiteColor];
  
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardChange:) name:UIKeyboardWillChangeFrameNotification object:nil];
  
    [self.view addSubview:self.jkTextView];
    [self.jkTextView addSubview:self.placeholderLabel];
    [self.view addSubview: self.tooBarView];
    [self.tooBarView addSubview:self.tooBarViewBtn];
  }
  
   #pragma mark 切换键盘
   -(void)switchKeyBoard{
  
     // 1.关闭键盘
     [self.jkTextView resignFirstResponder];
  
     // 2.设置inputView
     self.jkTextView.inputView = (self.jkTextView.inputView == nil) ? self.keyBoardView : nil;
  
    // 3.从新召唤出键盘
    [self.jkTextView becomeFirstResponder];
   }
  
   #pragma mark 监听键盘
   //实现接收到通知时的操作
   -(void)keyBoardChange:(NSNotification *)notification
   {
     //获取键盘弹出或收回时frame
     CGRect keyboardFrame = [notification.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
  
     //获取键盘弹出所需时长
    float duration = [notification.userInfo[UIKeyboardAnimationDurationUserInfoKey] floatValue];
  
    NSLog(@"键盘的弹出的时间=%lf",duration);
  
    /*
      工具条回弹是因为执行了两次动画, 而系统自带的键盘的动画节奏(曲线) 7
      7在apple API中并没有提供给我们, 但是我们可以使用
      7这种节奏有一个特点: 如果连续执行两次动画, 不管上一次有没有执行完毕, 都会立刻执行下一次
      也就是说上一次可能会被忽略
  
      如果将动画节奏设置为7, 那么动画的时长无论如何都会自动修改为0.5
  
      UIView动画的本质是核心动画, 所以可以给核心动画设置动画节奏
    */
   // 1.取出键盘的动画节奏
   float curve = [notification.userInfo[UIKeyboardAnimationCurveUserInfoKey] floatValue];
  
   [UIView animateWithDuration:duration animations:^{
    
    // 2.设置动画节奏
    [UIView setAnimationCurve:curve];
    
    self.tooBarView.y = keyboardFrame.origin.y - 64 - 44;
    
   }];
  }
  
  #pragma mark  textview的变化
  -(void)textViewDidChange:(UITextView *)textView{
  
      self.placeholderLabel.hidden = textView.hasText;
  }
  
  -(UITextView *)jkTextView{
  
     if (!_jkTextView) {
    
    _jkTextView = [[UITextView alloc]initWithFrame:CGRectMake(0, 0, CIO_SCREEN_WIDTH,CIO_SCREEN_HEIGHT-64)];
    [_jkTextView becomeFirstResponder];
    // UITextView可以垂直滑动弹出键盘
    _jkTextView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
    _jkTextView.alwaysBounceVertical = YES;
    _jkTextView.delegate = self;
    _jkTextView.backgroundColor = [UIColor whiteColor];
    _jkTextView.textColor = TitleBlackCOLOR;
    _jkTextView.font = [UIFont systemFontOfSize:16.f];
  }
  
   return _jkTextView;
  }
  
  -(UILabel *)placeholderLabel{
  
     if (!_placeholderLabel) {
    
     _placeholderLabel = [[UILabel alloc]initWithFrame:CGRectMake(5, 9, CIO_SCREEN_WIDTH-10, 22)];
     _placeholderLabel.text = @"分享新鲜事";
     _placeholderLabel.textColor = backGayCOLOR;
     _placeholderLabel.font = [UIFont systemFontOfSize:20];
    }
  
   return _placeholderLabel;
  }
  
  -(UIView *)tooBarView{
  
     if (!_tooBarView) {
  
       _tooBarView = [[UIView alloc]initWithFrame:CGRectMake(0, CIO_SCREEN_HEIGHT-64-44, CIO_SCREEN_WIDTH, 44)];
       _tooBarView.backgroundColor = [UIColor redColor];
     }
    return _tooBarView;
   }
  
   -(UIButton *)tooBarViewBtn{
  
      if (!_tooBarViewBtn) {
    
         _tooBarViewBtn = [[UIButton alloc]initWithFrame:CGRectMake(CIO_SCREEN_WIDTH-150, 0, 100, 44)];
         [_tooBarViewBtn addTarget:self action:@selector(switchKeyBoard) forControlEvents:UIControlEventTouchUpInside];
         [_tooBarViewBtn setTitle:@"切换键盘" forState:UIControlStateNormal];
         _tooBarViewBtn.backgroundColor = [UIColor purpleColor];
      }
     return _tooBarViewBtn;
   }
  
   -(UIView *)keyBoardView{
  
       if (!_keyBoardView) {
    
           _keyBoardView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, CIO_SCREEN_WIDTH, 100)];
          _keyBoardView.backgroundColor = [UIColor brownColor];
       }
  
     return _keyBoardView;
   }
  
   @end