[笔记] 将原生窗口嵌入到Swing/AWT当中

使用Canvas的窗口进行渲染

继承Canvas,在其paint中启动原生窗口渲染,并更新其大小

例子: 这里用到了JNA的Native.getComponentPointer

class MyNativeWindow(handle :PointerByReference) {
	fun start() {
		// 原生代码
	}
    fun setSize(x:Int, y:Int) {
		// 原生代码
    }
}

class MyNativeComponent() :Canvas() {
    private var initialized = false
    private var nativeWindow: MyNativeWindow? = null
    private var lastSize: Dimension? = null

    override fun paint(g: Graphics?) {
        val size = this.size
        if (size != lastSize) {
            lastSize = size
            if (nativeWindow != null) {
                this.updateSize()
            }
        }
        if (!initialized) {
            initialized = true
            Thread {
				nativeWindow(PointerByReference(Native.getComponentPointer(this))).start()
                this.updateSize()
            }.start()
        }
    }

    private fun updateSize() {
        nativeWindow?.setSize(lastSize!!.width, lastSize!!.height)
    }
}

参考实例: https://github.com/Casterlabs/Webview/blob/main/src/main/java/dev/webview/Webview.java#L41

特点:

• 可作为控件使用
• 需要原生窗口支持在非主线程中运行

作为子窗口(Windows)

这里用到了jna-platform的User32.INSTANCE.SetParent

User32.INSTANCE.SetParent(HWND(pWin),HWND(getComponentPointer(c)))

其中c为Canvas,pWin为原生窗口指针

特点:

• 仅支持Windows
• 需要窗口无边框
• 无需为原生窗口提供HANDLE