想要将时间戳添加到中心对齐textview，并将标签调整为右对齐

Question

在我的一个聊天应用程序中，我使用了标签和textview。 UITextView是中心对齐，另外一个标签添加到子视图并根据正常工作的文本调整位置..

但我的需要是使它类似于whatsapp应用程序。如果文字很小而且标签可以在同一行内调整，那么气泡不应该扩展到两行并调整为单行。

我附上的图片将清除要求。

提前致谢。

Answer 1

我可以在 Textkit- exclusionPaths的帮助下执行此操作。

    CGSize sizelbl = _lbl_Timestamp.frame.size;
[_lbl_Timestamp
 setFrame:CGRectMake(CGRectGetMaxX(_txtView.frame) - sizelbl.width - 5,
                     CGRectGetMaxY(_txtView.frame) - sizelbl.height - 5 - 3,
                     sizelbl.width, sizelbl.height)];


CGRect ovalFrame = [_txtView convertRect:_lbl_Timestamp.bounds fromView:_lbl_Timestamp];

// Since text container does not know about the inset, we must shift the frame to container coordinates
ovalFrame.origin.x -= _txtView.textContainerInset.left;
ovalFrame.origin.y -= _txtView.textContainerInset.top;

// Simply set the exclusion path
UIBezierPath *ovalPath = [UIBezierPath bezierPathWithOvalInRect: ovalFrame];
_txtView.textContainer.exclusionPaths = @[ovalPath];

Answer 2

以下是您的解决方案：

- (void) updateLabelFrame {

    /* self.label.frame is your required label */

    CGRect lblRect = self.label.frame;
    CGSize maxSize = CGSizeMake(self.label.frame.size.width, MAXFLOAT);

    /* Get exptected rect for label */
    CGRect labelRect = [self.label.text boundingRectWithSize:maxSize options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName:self.label.font} context:nil];

    /* Caculate number of lines for label */
    CGFloat labelHeight = labelRect.size.height;
    int lines = labelHeight / 16; /* 16 is Default label height, Change with your pre-set label height */ 
    [self.label setNumberOfLines:lines];

    /* Set height of your label */
    lblRect.size.height = labelHeight;
    [self.label setFrame:lblRect];

    /* Change here your view height according to label height */

    NSString *trimmedText = [self.label.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];

    if ([trimmedText length] > 0) {

        CGFloat viewHeight = self.label.frame.origin.y + self.label.frame.size.height + /* ADD PADDING SPACE */ 20;

        CGRect viewRect = self.frame; /* SET VIEW FRAME */
        viewRect.size.height = viewHeight;
        [self setFrame:viewRect];
    }
}