如何创建一个UIButton来呈现与UIBarButtonItem相同的效果？

Question

我想创建一个 UIButton，但与 UIBarButtonItem 的外观相同。怎么办呢？？

Answer 1

发现这个有用

https://github.com/0xced/UIKit-Artwork-Extractor

Answer 2

在导航栏之外，创建与 UIBarButton 样式相同的按钮的唯一方法是自己实际创建必要的背景图像。没有任何类可供您用于此目的（显然有一个类，但它被视为私有 API，使用它将使您的应用程序被拒绝）。

Answer 3

您可以通过将按钮图像上的 renderMode 设置为 UIImageRenderingModeAlwaysTemplate 来实现此目的。这将使它继承其祖先视图的tintColor。

以下是如何在 Swift 中执行此操作（无论如何，对于一种控制状态）：

if let i = myBtn?.imageForState(UIControlState.Normal) {
    if i.renderingMode != UIImageRenderingMode.AlwaysTemplate {
        let newImage = i.imageWithRenderingMode(UIImageRenderingMode.AlwaysTemplate)
        myBtn?.setImage(newImage, forState: UIControlState.Normal)
    }
}

Answer 4

我通过另一个论坛找到了这个.. GradientButton 类。

http://code.google.com/p/iphonegradientbuttons/downloads/list

Answer 5

可能有点晚了，但万一有人遇到这个问题，还有另一种不使用图像的可能性。我用 QuartzCore 代替。

这就是我所做的：

MyUIButton.h

#import <QuartzCore/QuartzCore.h>

@interface MyUIButton : UIView { //i think you can also subclass from UIButton, but i use a view to be more flexible

    UIButton *_myInnerButton;
}

- (void) addTarget:(id)target action:(SEL)action forControlEvents:(UIControlEvents)controlEvents;

- (void) removeTarget:(id) target action:(SEL)action forControlEvents:(UIControlEvents)controlEvents;

@end

MyUIButton.m

#import "MyUIButton.h"

@implementation MyUIButton


- (void) dealloc {

    if (_myInnerButton != nil) {

        [_myInnerbutton removeFromSuperview];

        _myInnerbutton = nil;
    }

    [super dealloc];
}

- (id) initWithFrame:(CGRect)frame {

    self = [super initWithFrame:frame];

    if (self) {

        self.clipsToBounds = YES;


        _myInnerButton = [UIButton buttonWithType:UIButtonTypeCustom];

        [self addSubview:_myInnerButton];


        CGRect innerButtonRect = CGRectZero;

        innerButtonRect.size = self.frame.size;

        _myInnerButton.frame = innerButtonRect;


        CGRect iOSLookalikeViewRect = innerButtonRect;

        iOSLookalikeViewRect.origin.height = -innerButtonRect.size.height/2;


        UIView *iOSButtonView = [[UIView alloc] initWithFrame:iOSLookalikeViewRect];

        iOSButtonView.layer.cornerRadius = 3;

        [self insertSubview:iOSButtonView belowSubview:_myInnerButton];

        UIColor *whiteColor = [UIColor colorWithRed:1 green:1 blue:1 alpha:0.3];

        UIColor *whiteColor2 = [UIColor colorWithRed:1 green:1 blue:1 alpha:0.1];

        [self setGradientColors:[NSArray arrayWithObjects:whiteColor.CGColor, whiteColor2.CGColor, nil] forView:iOSButtonView];

        [iOSButtonView release];
    }

    return self;
}

- (void) setGradientColors:(NSArray*) gradientColors forView:(UIView*) view {

    CAGradientLayer *gradient = [CAGradientLayer layer];
    gradient.frame = view.bounds;
    gradient.colors = gradientColors;
    gradient.cornerRadius = view.layer.cornerRadius;

    [view.layer insertSublayer:gradient atIndex:1];

    [view.layer setRasterizationScale:[UIScreen mainScreen].scale]; //Optional for performance issues, can be removed also
}

//Implementation of the public methods not included, but just asign the methods to the _myInnerButton
@end

希望对某人有帮助