PencilKit 加号按钮未显示在 ToolPicker 上

Question

我正在尝试在画布上使用 ToolPicker，但这里有：

我想要（按钮 + 和文本、形状...）：

如何将文本、形状添加到画布上的 ToolPicker 中？

struct MyCanvas: UIViewRepresentable {
        var canvasView: PKCanvasView
        let picker = PKToolPicker.init()
        
        func makeUIView(context: Context) -> PKCanvasView {
            self.canvasView.tool = PKInkingTool(.pen, color: .black, width: 15)
            self.canvasView.isOpaque = false
            self.canvasView.backgroundColor = UIColor.clear
            self.canvasView.becomeFirstResponder()
    
           let imageView = UIImageView(image: UIImage(named: "badmintoncourt"))
            let subView = self.canvasView.subviews[0]
                subView.addSubview(imageView)
                subView.sendSubviewToBack(imageView)
            return canvasView
        }
        
        func updateUIView(_ uiView: PKCanvasView, context: Context) {
            picker.addObserver(canvasView)
            picker.setVisible(true, forFirstResponder: uiView)
            DispatchQueue.main.async {
                uiView.becomeFirstResponder()
            }
        }
    }