从xib加载UIView需要使用标签文本动态调整大小

Question

我正在从 xib 加载自定义UIView。多行时UILabel文本可能很长。 UIButton下方UILabel。 UIView正在从xib 加载为自定义子类。

我需要调整整个UIView的大小，具体取决于文本的数量。但它保持在 xib 中设置的框架高度。如何使用UIView文本弹性调整UILabel的大小，以及保持所有autolayout约束不变。

我需要UIView框架尺寸，因为我将它显示为带有动画的顶部的下拉视图。

UILabel的大小正常。但是文字超出了UIView。 UIView需要调整大小，我需要更新的帧大小。

问题在这里显示，

这些行修复了 autoresize ，但我不确定这是正确的方法。

CGRect myFrame = self.frame;
self.frame = CGRectMake(myFrame.origin.x, myFrame.origin.y, 
    myFrame.size.width, 
    self.labelMessage.frame.size.height + self.btClose.frame.size.height + 16); // magic number!

全班，

    #import "MessageView.h"

@implementation MessageView

@synthesize systemMessage = _systemMessage; //otherwise setter is not called

// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
    [self updateUI];
}

- (void) updateUI {
//  DLog(@"%@", _systemMessage);
    if (_systemMessage.actionType == MessageActionDisappearing || _systemMessage.actionType == MessageActionDismissableRetry) {
        _btTryAgain.hidden = NO;
    } else {
        _btTryAgain.hidden = YES;
    }
    if (_systemMessage.actionType == MessageActionDismissable || _systemMessage.actionType == MessageActionDismissableRetry) {
        _btClose.hidden = NO;
    } else {
        _btClose.hidden = YES;
    }
    _borderView.backgroundColor = [self getBorderColor];
    _labelMessage.text = _systemMessage.message;
    CGRect myFrame = self.frame;
    self.frame = CGRectMake(myFrame.origin.x, myFrame.origin.y, myFrame.size.width,
                            self.labelMessage.frame.size.height + self.btClose.frame.size.height + 16); // magic number!
}

- (instancetype)initWithFrame:(CGRect)frame {
//  DLog(@"");
    self = [super initWithFrame:frame];
    [self xibSetup];
    return self;
}

- (void)awakeFromNib {
//  DLog(@"");
    [super awakeFromNib];
}

- (instancetype)initWithCoder:(NSCoder *)aDecoder {
//  DLog(@"");
    self = [super initWithCoder:aDecoder];
    if (self.subviews.count == 0) {
        [self xibSetup];
    }
    return self;
}

- (void) xibSetup {
    UIView *v = [self loadViewFromXib];
    v.frame = self.bounds;
    [self addSubview:v];
}

- (UIView *)loadViewFromXib {
    UIView *v = [[[NSBundle mainBundle] loadNibNamed:@"MessageView" owner:self options:nil] firstObject];
    return v;
}

// isn't called!
- (CGSize)intrinsicContentSize
{
    DLog(@"%@", _labelMessage.text);
    CGSize size = self.labelMessage.intrinsicContentSize;
    size.height = size.height + _btTryAgain.frame.size.height + 16;
    size.width = self.intrinsicContentSize.width;
//  size.width  += 16;
    return size;
}

#pragma mark - Methods

/** Refresh the UI when message content is changed. */
- (void)setSystemMessage:(SystemMessage *)systemMessage {
    _systemMessage = systemMessage;
    [self updateUI];
}

- (UIColor *)getBorderColor {
    if (_systemMessage.messageType == MessageTypeWarning) {
        return [UIColor yellowColor];
    } else if (_systemMessage.messageType == MessageTypePositive) {
        return [UIColor greenColor];
    } else {
        return [UIColor blueColor];
    }
}

- (void) hideButtonWithId:(MessageViewButtonId)buttonId {
    if (buttonId == MessageViewButtonIdClose) {
        _btClose.hidden = YES;
    } else if (buttonId == MessageViewButtonIdTryAgain) {
        _btTryAgain. hidden = YES;
    }
}

- (NSString *)description {
    return [NSString stringWithFormat:@"%@, systemMessage: %@", [super description], _systemMessage];
}

#pragma mark - Actions

- (IBAction)didPressCloseButton:(id)sender {
    if ([_delegate respondsToSelector:@selector(messageView:didPressButtonWithId:)]) {
        [_delegate messageView:self didPressButtonWithId:MessageViewButtonIdClose];
    }
}

- (IBAction)didPressTryAgainButton:(id)sender {
    if ([_delegate respondsToSelector:@selector(messageView:didPressButtonWithId:)]) {
        [_delegate messageView:self didPressButtonWithId:MessageViewButtonIdTryAgain];
    }
}