我有uilabel,我需要它能够支持复制和粘贴(实际上只复制,因为它是只读的)。我对uilabel进行了子类化以支持copy,它工作得很好。我还添加了文本突出显示,这样用户在单击标签时就知道他到底在复制什么。
我的问题是,当用户单击其他地方时,我不知道如何取消突出显示。复制气泡消失,但我没有收到任何回调,因此文本保持突出显示。有没有特别的回拨我错过了,我可以使用,还是我必须想出一些肮脏的黑客?或者,是否有更标准的方法来突出显示uilabel中的文本,我不知道这会像复制气泡一样自动处理?
这里是我的自定义uilabel代码:
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender {
if(action == @selector(copy:)) {
return YES;
}
else {
return [super canPerformAction:action withSender:sender];
}
}
- (BOOL)becomeFirstResponder {
if([super becomeFirstResponder]) {
self.highlighted = YES;
UIMenuController *menu = [UIMenuController sharedMenuController];
[menu setTargetRect:self.bounds inView:self];
[menu setMenuVisible:YES animated:YES];
return YES;
}
return NO;
}
- (BOOL)resignFirstResponder {
if([super resignFirstResponder]) {
self.highlighted = NO;
UIMenuController *menu = [UIMenuController sharedMenuController];
[menu setMenuVisible:NO animated:YES];
[menu update];
return true;
}
return false;
}
- (void)copy:(id)sender {
UIPasteboard *board = [UIPasteboard generalPasteboard];
[board setString:self.text];
self.highlighted = NO;
[self resignFirstResponder];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if([self isFirstResponder]) {
[self resignFirstResponder];
}
else if([self becomeFirstResponder]) {
}
}
- (void)setHighlighted:(BOOL)hl {
[super setHighlighted:hl];
[self setNeedsLayout];
}
- (void)drawRect:(CGRect)rect {
[super drawRect:rect];
if(self.highlighted) {
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextSetRGBFillColor(ctx, 0.3, 0.8, 1.0, 0.3);
CGContextAddRect(ctx, CGRectMake(0, 0, [self textRectForBounds:self.frame limitedToNumberOfLines:1].size.width, self.frame.size.height));
CGContextFillPath(ctx);
}
}
感谢您的帮助!