实现点击label 弹出UIMenuController

首先说一说UIMenuController

• 默认情况下, 有以下控件已经支持UIMenuController
  • UITextField
  • UITextView
  • UIWebView

也可以 让其他控件也支持UIMenuController(比如UILabel)

• 自定义UILabel
• 重写2个方法

/**
 * 让label有资格成为第一响应者
 */
- (BOOL)canBecomeFirstResponder
{
    return YES;
}

/**
 * label能执行哪些操作(比如copy, paste等等)
 * @return  YES:支持这种操作
 */
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
    if (action == @selector(cut:) || action == @selector(copy:) || action == @selector(paste:)) return YES;

    return NO;
}

//给label添加点击手势
- (void)setGestureRecognizer
{
    self.userInteractionEnabled = YES;
    [self addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(labelClick)]];
}

- (void)labelClick
{
    // 1.label要成为第一响应者(作用是:告诉UIMenuController支持哪些操作, 这些操作如何处理)
    [self becomeFirstResponder];
    
    // 2.显示MenuController
    UIMenuController *menu = [UIMenuController sharedMenuController];
    // targetRect: MenuController需要指向的矩形框
    // targetView: targetRect会以targetView的左上角为坐标原点
    [menu setTargetRect:self.bounds inView:self];
//    [menu setTargetRect:self.frame inView:self.superview];
    [menu setMenuVisible:YES animated:YES];
}

• 实现各种操作方法

- (void)cut:(UIMenuController *)menu
{
    // 将自己的文字复制到粘贴板
    [self copy:menu];

    // 清空文字
    self.text = nil;
}

- (void)copy:(UIMenuController *)menu
{
    // 将自己的文字复制到粘贴板
    UIPasteboard *board = [UIPasteboard generalPasteboard];
    board.string = self.text;
}

- (void)paste:(UIMenuController *)menu
{
    // 将粘贴板的文字 复制 到自己身上
    UIPasteboard *board = [UIPasteboard generalPasteboard];
    self.text = board.string;
}

自定义UIMenuController内部的Item

• 添加item

// 添加MenuItem(点击item, 默认会调用控制器的方法)
UIMenuItem *spot = [[UIMenuItem alloc] initWithTitle:@"支持" action:@selector(ding:)];
UIMenuItem *replay = [[UIMenuItem alloc] initWithTitle:@"回复" action:@selector(replay:)];
UIMenuItem *report = [[UIMenuItem alloc] initWithTitle:@"举报" action:@selector(report:)];
menu.menuItems = @[spot, replay, report];