自定义 UIPopover

Posted 2023-03-12

【中文标题】自定义 UIPopover

【英文标题】：Customizing UIPopover

【发布时间】：2013-08-14 17:39:32

【问题描述】：

我想改变 UIPopover 的颜色。我创建了一个自定义弹出框，但我不知道为什么不显示边框。

这是显示 UIPopover 的 MainViewController 文件：

@synthesize btnShowPopover;
UIPopoverController *popover;
bool isPopoverOpen = false;

- (void)viewDidLoad

    [super viewDidLoad];

    controller = [[Pop1 alloc] initWithNibName:@"Pop1" bundle:nil];
    popoverController = [[UIPopoverController alloc] initWithContentViewController:controller];


- (IBAction)showPopover:(UIButton *)sender

    if(!isPopoverOpen)


        Pop1 *firstViewCtrl = [[Pop1 alloc] init];

        UINavigationController *navbar = [[UINavigationController alloc] initWithRootViewController:firstViewCtrl];

        navbar.contentSizeForViewInPopover = CGSizeMake(300, 300);
        popover = [[UIPopoverController alloc] initWithContentViewController:navbar];

        popover.popoverBackgroundViewClass = [Back class];

        popover.delegate = self;
        popover.popoverContentSize = CGSizeMake(300, 300);

        CGRect popRect = CGRectMake(self.btnShowPopover.frame.origin.x,
                                    self.btnShowPopover.frame.origin.y,
                                    self.btnShowPopover.frame.size.width,
                                    self.btnShowPopover.frame.size.height);
        [popover presentPopoverFromRect:popRect
                                 inView:self.view
               permittedArrowDirections:UIPopoverArrowDirectionAny
                               animated:YES];

        isPopoverOpen = true;
    else
        [popover dismissPopoverAnimated:YES];
        isPopoverOpen = false;
    

这是继承自 UIPopoverBackgroundView 的 Back 类。

#import "Back.h"
#define kArrowBase 30.0f
#define kArrowHeight 20.0f
#define kBorderInset 8.0f
#define kBorderInset 0.0f

@interface Back ()
@property (nonatomic, strong) UIImageView *arrowImageView;
- (UIImage *)drawArrowImage:(CGSize)size;
@end

@implementation Back

@synthesize arrowDirection  = _arrowDirection;
@synthesize arrowOffset     = _arrowOffset;

- (id)initWithFrame:(CGRect)frame

    self = [super initWithFrame:frame];
    if (self) 
        self.backgroundColor = [UIColor grayColor];

        UIImageView *arrowImageView = [[UIImageView alloc] initWithFrame:CGRectZero];
        self.arrowImageView = arrowImageView;
        [self addSubview:self.arrowImageView];
        // Initialization code
    
    return self;


+ (CGFloat)arrowBase

    return kArrowBase;

+ (CGFloat)arrowHeight

    return kArrowHeight;

+ (UIEdgeInsets)contentViewInsets

    return UIEdgeInsetsMake(kBorderInset, kBorderInset, kBorderInset,       kBorderInset);


+ (BOOL)wantsDefaultContentAppearance

    return NO;


- (UIImage *)drawArrowImage:(CGSize)size

    UIGraphicsBeginImageContextWithOptions(size, NO, 0);
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    [[UIColor clearColor] setFill];
    CGContextFillRect(ctx, CGRectMake(0.0f, 0.0f, size.width, size.height));
    CGMutablePathRef arrowPath = CGPathCreateMutable();
    CGPathMoveToPoint(arrowPath, NULL, (size.width/2.0f), 0.0f);
    CGPathAddLineToPoint(arrowPath, NULL, size.width, size.height);
    CGPathAddLineToPoint(arrowPath, NULL, 0.0f, size.height);
    CGPathCloseSubpath(arrowPath);
    CGContextAddPath(ctx, arrowPath);
    CGPathRelease(arrowPath);
    UIColor *fillColor = [UIColor yellowColor];
    CGContextSetFillColorWithColor(ctx, fillColor.CGColor);
    CGContextDrawPath(ctx, kCGPathFill);
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;


- (void)layoutSubviews

    [super layoutSubviews];
    CGSize arrowSize = CGSizeMake([[self class] arrowBase], [[self class] arrowHeight]);
    self.arrowImageView.image = [self drawArrowImage:arrowSize];
    self.arrowImageView.frame = CGRectMake(((self.bounds.size.width - arrowSize.width) ,kBorderInset), 0.0f, arrowSize.width, arrowSize.height);

我正在尝试创建这样的弹出框（我不是在谈论弹出框内容）

我只想为边框、背景和箭头设置自定义颜色。实际上我可以设置颜色但不显示边框。如何显示边框？

【问题讨论】：

当您从wantsDefaultContentAppearance 返回YES 时会发生什么？文档说了一些关于绘制插图的事情。可能是相关的。

【参考方案1】：

是的，我找到了解决方案。

(UIEdgeInsets)contentViewInsets 方法设置弹出框的缩进。

+ (UIEdgeInsets)contentViewInsets

    return UIEdgeInsetsMake(kBorderInset, 10.0f, 10.0f, 10.0f);

【讨论】：

你已经实现了方法，但是常量是#define kBorderInset 0.0f。

@iMartin 是的，我意识到我的错误；）

我发现另一个教程准确地解释了我想要什么blog.teamtreehouse.com/…