iphone - 如果你的 UIView 只是一个容器，需要重写drawrect吗？

Question

根据 Apple 的文档，“如果子类是其他 View 的容器，则子类不需要覆盖 -[UIView drawRect:]。”

我有一个自定义的 UIView 子类，它实际上只是其他 View 的容器。然而所包含的 View 并没有被绘制出来。以下是设置自定义 UIView 子类的相关代码:

- (id)initWithFrame:(CGRect)frame
{
    if ((self = [super initWithFrame:frame]))
    {
        // Consists of both an "on" light and an "off" light. We flick between the two depending upon our state.
        self.onLight = [[[LoyaltyCardNumberView alloc] initWithFrame:frame] autorelease];
        self.onLight.backgroundColor = [UIColor clearColor];
        self.onLight.on = YES;
        [self addSubview:self.onLight];

        self.offLight = [[[LoyaltyCardNumberView alloc] initWithFrame:frame] autorelease];
        self.offLight.backgroundColor = [UIColor clearColor];
        self.offLight.on = NO;
        [self addSubview:self.offLight];

        self.on = NO;
    }
    return self;
}

当我运行显示此自定义 UIView 的代码时，没有任何显示。但是当我添加一个drawRect方法时...

    - (void)drawRect:(CGRect)rect
    {
        [self.onLight drawRect:rect];
        [self.offLight drawRect:rect];
    }

...显示 subview 。 (显然，这不是这样做的正确方法，不仅因为它与文档所说的相反，而且因为它总是显示两个 subview ，完全忽略我的 UIView 中设置隐藏属性的其他一些代码 View 之一，它忽略 z 顺序等)

无论如何，主要问题是:当我不重写drawRect时，为什么我的 subview 不显示:？

谢谢!

更新:

为了确保问题不在于我的自定义 subview ，我还添加了 UILabel。所以代码如下:

- (id)initWithFrame:(CGRect)frame
{
    if ((self = [super initWithFrame:frame]))
    {
        // Consists of both an "on" light and an "off" light. We flick between the two depending upon our state.
        self.onLight = [[[LoyaltyCardNumberView alloc] initWithFrame:frame] autorelease];
        self.onLight.backgroundColor = [UIColor clearColor];
        self.onLight.on = YES;
        [self addSubview:self.onLight];

        self.offLight = [[[LoyaltyCardNumberView alloc] initWithFrame:frame] autorelease];
        self.offLight.backgroundColor = [UIColor clearColor];
        self.offLight.on = NO;
        [self addSubview:self.offLight];

        self.on = NO;

        UILabel* xLabel = [[[UILabel alloc] initWithFrame:frame] autorelease];
        xLabel.text = @"X";
        [self addSubview:xLabel];
    }
    return self;

“X”也不显示。

更新2:

这是调用我的自定义 UIView (OffOnLightView) 的代码:

            // Container for all of the OffOnLightViews...
            self.stampSuperView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)] autorelease];
            [self.view addSubview:self.stampSuperView];

            // Draw the stamps into the 'stamp superview'.
            NSInteger numberOfCardSpaces = (awardType == None) ? 3 : 10;
            for (NSInteger i = 1; i <= numberOfCardSpaces; i++)
            {
                OffOnLightView* newNumberView = [[[OffOnLightView alloc] initWithFrame:[self frameForStampWithOrdinal:i awardType:awardType]] autorelease];
                newNumberView.on = (i <= self.place.checkInCount.intValue);
                newNumberView.number = [NSString stringWithFormat:@"%d", i];
                [self.stampSuperView addSubview:newNumberView];
            }

Answer 1

您的 subview 的框架应初始化为父 uiview 的边界。 subview 位于相对于父 View 框架的不同坐标系中。

self.onLight = [[[LoyaltyCardNumberView alloc] initWithFrame:self.bounds] autorelease];