iOS UINavigationBar按钮图像对于pdf矢量图标来说太小

Question

我在UINavigationBar rightBarButtonItem中设置了pdf矢量图像，但是它仍然显示得太小。

  

如何在UINavigationBar中显示完整尺寸的矢量图像？

我尝试使用以下代码：-
第一种方式：-

UIBarButtonItem *barbutton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@“imgRightArrow”] style:UIBarButtonItemStylePlain target:nil action:nil];
self.navigationItem.rightBarButtonItem = barbutton;

第二种方式：-

UIImage *image = [UIImage imageNamed:@“imgRightArrow”]
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setImage:image forState:UIControlStateNormal];
[button.imageView setContentMode:UIViewContentModeScaleToFill];
button.frame = CGRectMake(0, 0, 35, 35);
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];

Answer 1

问题是矢量图像的大小以像素为单位声明。对于tabBarItems和UIBarButtonItem，这确实很重要。我用这个UIImage扩展解决了这个问题。

func resize(to size: CGFloat) -> UIImage {
    let newSize = CGSize(width: size, height: size)
    return resize(newSize: newSize)
}


private func resize(newSize: CGSize) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0)
    self.draw(in: CGRect(origin: CGPoint.zero, size: newSize))
    let newImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    return newImage ?? UIImage()
}

 private lazy var sendAction = UIBarButtonItem(image: yourImage.resize(to: 32),
                                              style: .done,
                                              target: self,
                                              action: #selector(someAction))

Answer 2

我要做的是保存图标三遍，分别为25px，50px，75px，并将这三个添加到素材资源（x1，x2，x3）中，您不必在代码中设置图标的大小