自定义UIPopoverBackgroundView：没有投影 [英] Custom UIPopoverBackgroundView: no drop shadow

问题描述

我用这个好的教程来创建自定义UIPopoverBackgroundView类。

I've used this good tutorial to create a custom UIPopoverBackgroundView class.

效果很好。唯一的问题是我没有得到典型的UIPopoverController投影，我想要它。我已经尝试在我的UIPopoverBackgroundView实例层上指定它但没有成功。我的UIPopoverController实例似乎没有公共视图来操作。将其添加到弹出窗口内容也不起作用。

It works well. The only problem is that I am not getting the typical UIPopoverController drop shadow and I want it. I've tried specifying it on the layer of my UIPopoverBackgroundView instance without success. My instance of UIPopoverController doesn't seem to have a public view to manipulate. Adding it to the popover content also doesn't work.

可能非常简单：如何在使用自定义UIPopoverBackgroundView类时添加阴影？

// UIPopoverBackgroundView.m

-(id)initWithFrame:(CGRect)frame{
    if (self = [super initWithFrame:frame]) {
        _borderImageView = [[UIImageView alloc] initWithImage:[[UIImage imageNamed:@"bg-popover.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(CAP_INSET,CAP_INSET,CAP_INSET,CAP_INSET)]];

        _arrowView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"bg-popover-arrow.png"]];

        [self addSubview:_borderImageView];
        [self addSubview:_arrowView];

        self.layer.shadowOffset = CGSizeMake(50, 50);
        self.layer.shadowColor = [[UIColor blackColor] CGColor];
    }

    return self;
}

推荐答案

好的，想通了。我需要将阴影添加到 borderImageView ，而不是弹出窗口实例的视图。

Ok, figured it out. I needed to add the drop shadow to the borderImageView, not the view of the popover instance.

- (id)initWithFrame:(CGRect)frame
{
    if (self = [super initWithFrame:frame]) {
        _borderImageView = [[UIImageView alloc] initWithImage:[[UIImage imageNamed:@"bg-popover.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(CAP_INSET,CAP_INSET,CAP_INSET,CAP_INSET)]];

        _arrowView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"bg-popover-arrow.png"]];

        [self addSubview:_borderImageView];
        [self addSubview:_arrowView];

        _borderImageView.layer.cornerRadius = 5.0f;
        _borderImageView.layer.masksToBounds = NO;
        _borderImageView.layer.borderWidth = 1.0f;
        _borderImageView.layer.borderColor = [UIColor blackColor].CGColor;

        _borderImageView.layer.shadowColor = [UIColor blackColor].CGColor;
        _borderImageView.layer.shadowOpacity = 0.8;
        _borderImageView.layer.shadowRadius = 50;
        _borderImageView.layer.shadowOffset = CGSizeMake(-10.0f, 10.0f);
    }

    return self;
}

这篇关于自定义UIPopoverBackgroundView：没有投影的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！