Xcode使用条形图中的PDF图像按钮项目大小太大-XcodeUsePDFImageinBarButtonItemSizeTooBig

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Using Code what I do when the image size is too big, I resize the UIImage before rendering/setting on the UIControl. I have this extension on UIImage that helps re-scale an image.

使用Code我在图像大小太大时所做的事情,我在UIControl上渲染/设置之前调整UIImage的大小。我在UIImage上有这个扩展,有助于重新缩放图像。

// MARK: - Used to scale UIImages
extension UIImage {
    func scaleTo(_ newSize: CGSize) -> UIImage {
        UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0)
        self.draw(in: CGRect(x: 0, y: 0, width: newSize.width, height: newSize.height))
        let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return newImage
    }
}

Using this would look like this

使用它看起来像这样

let defaultImage = UIImage(named: "someimagenamehere")?
    .scaleTo(CGSize(width: 40, height: 40))

self.navigationItem.leftBarButtOnItem= UIBarButtonItem(
    image: defaultImage,
    style: .plain,
    target: self,
    action: #selector(self.someselectorhere(_:)))

UPDATE: This is what it would look like using @IBDesignable and @IBInspectable

更新:这就是使用@IBDesignable和@IBInspectable的样子

@IBDesignable
class CustomBarButtonItem: UIBarButtonItem {

    @IBInspectable
    var scaledHeight: CGFloat = 0 {
        didSet {
            self.image = self.image?.scaleTo(CGSize(width: self.scaledHeight, height: self.scaledWidth))
        }
    }

    @IBInspectable
    var scaledWidth: CGFloat = 0 {
        didSet {
            self.image = self.image?.scaleTo(CGSize(width: self.scaledHeight, height: self.scaledWidth))
        }
    }
}