iOS: 如何将 TabBar 的 UIImage 中的特定颜色替换为另一种颜色（select 和 unselect）？

Question

我想在我的 UITabBar 中用另一种颜色替换选中的颜色。目的是获得一张我可以通过编程更改颜色的图像。

我该怎么做？

let tabBarItem = UITabBarItem(title: menuName, image: unselectedImage, selectedImage: selectedImage)

我检查了那张票没有成功：
link1, link2

Answer 1

我遇到了同样的问题。你应该创建一个背景为白色的 png，并将另一个图像放在上面具有半透明背景 png。

（我认为你应该使用质量更好的图像，因为你的照片看起来很奇怪）

                let iconWhite: UIImage? = self.load(fileName: "APP/icones/\(iconName).png")?.withRenderingMode(UIImage.RenderingMode.alwaysOriginal)
                        
                        
        //UNSELECT IMAGE
                        var unselectedImgBack = UIImage(named: "white.png")
                        var unselectedImgFront = iconWhite?.overlayImage(color: UIColor.black)
                        
                        let size = unselectedImgFront?.size
                        unselectedImgBack = unselectedImgBack?.resized(to: size!)
                        UIGraphicsBeginImageContext(size!)
                        let areaSize = CGRect(x: 0, y: 0, width: size!.width, height: size!.height)
                        unselectedImgBack!.draw(in: areaSize)
                        unselectedImgFront!.draw(in: areaSize, blendMode: .normal, alpha: 1)
                        unselectedImgFront = UIGraphicsGetImageFromCurrentImageContext()!
                        UIGraphicsEndImageContext()
                        
                        let unselectedImage =  unselectedImgFront!.withRenderingMode(UIImage.RenderingMode.alwaysOriginal)
                        
        //SELECT IMAGE
                        
                        var selectedImgBack = UIImage(named: "white.png")
                        var selectedImgFront = iconWhite
                        
                        let scanner2 = Scanner(string: color)
                        var value: UInt64 = 0
                        
                        if scanner2.scanHexInt64(&value) {
                            print("Decimal: \(value)")
                            print("Hex: 0x\(String(value, radix: 16))")
                        }
                        selectedImgBack = selectedImgBack?.overlayImage(color: UIColor.init(rgb: Int(value)))

                        selectedImgBack = selectedImgBack?.resized(to: size!)
                        UIGraphicsBeginImageContext(size!)
                        selectedImgBack!.draw(in: areaSize)
                        selectedImgFront!.draw(in: areaSize, blendMode: .normal, alpha: 0.8)
                        selectedImgFront = UIGraphicsGetImageFromCurrentImageContext()!
                        UIGraphicsEndImageContext()
                        
                        let selectedImage = selectedImgFront!.withRenderingMode(UIImage.RenderingMode.alwaysOriginal)

iOS: 如何将 TabBar 的 UIImage 中的特定颜色替换为另一种颜色（select 和 unselect）？

iOS: How to replace a specific color by another in a UIImage of a TabBar (select and unselect)?

uitabbar

ios

uigraphicscontext

swift