仿真器中
1，格子状显示

把下面这句注释掉，就可能会这么显示

WM_SetCreateFlags(WM_CF_MEMDEV);

2，显示一副灰度图

很有可能你是这么写的

也就是

hMemDev = GUI_MEMDEV_CreateFixed(0, 0, 200, 200, GUI_MEMDEV_HASTRANS, GUI_MEMDEV_APILIST_32, GUI_COLOR_CONV_8888);

3,
它的调用位置

WM_SetCreateFlags(WM_CF_MEMDEV);

这样调用

WM_SetCreateFlags(WM_CF_MEMDEV);
  / / 初始化 emWin
    GUI_Init();

显示

调用方式二:

    // 初始化 emWin
    GUI_Init();

	// 初始化窗口管理
	WM_SetCreateFlags(WM_CF_MEMDEV);

啥都没显示

总结就是先调用
WM_SetCreateFlags(WM_CF_MEMDEV);
再调用
GUI_Init();

但是能别调用就别调用

4，想显示成

把 WM_SetCreateFlags(WM_CF_MEMDEV); 注释掉就好了。
但是这又不是我想要的

最后的demo

显示的图像。
一点一点的分析吧，，，必须要知道每个函数的意思，而且有的函数跟自己的理解不一样。

源码：

#include "GUI.h"
#include "WM.h"

// 子窗口回调函数
static void _cbChildWindow(WM_MESSAGE* pMsg) {
    GUI_MEMDEV_Handle hMemDev;
    switch (pMsg->MsgId) {
    case WM_PAINT:
       
        //设置颜色并绘制矩形
        int x = WM_GetWindowOrgX(pMsg->hWin);//这里是相对屏幕坐标
        int y = WM_GetWindowOrgY(pMsg->hWin);//这里是相对屏幕的坐标
        int w = WM_GetWindowSizeX(pMsg->hWin);
        int h = WM_GetWindowSizeY(pMsg->hWin);
        GUI_RECT Rect0;
        WM_GetClientRect(&Rect0);//这里是相对父类的坐标（0,0,79,79）
        GUI_RECT Rect1;
        WM_GetWindowRect(&Rect1); //这里是相对屏幕的坐标（40,40,119,119）

        GUI_RECT Rect2;
        WM_GetInsideRect(&Rect2);//这里得到的是父类相对他父类的坐标，（0,0,249,249）
        GUI_SetColor(GUI_WHITE);
        GUI_FillRect(Rect2.x0, Rect2.y0, Rect2.x1, Rect2.y1);

        //printf("Child Rect: x0=%d, y0=%d, x1=%d, y1=%d\n", Rect2.x0, Rect2.y0, Rect2.x1, Rect2.y1);


        // 创建一个 80x120 的内存设备
        hMemDev = GUI_MEMDEV_CreateFixed(0, 0, 80, 120, GUI_MEMDEV_NOTRANS, GUI_MEMDEV_APILIST_32, GUICC_8888);
        GUI_MEMDEV_Select(hMemDev);
        GUI_SetBkColor(GUI_RED);
        //GUI_SetBkColor(GUI_TRANSPARENT);
        GUI_Clear();
        // 在内存设备中绘制内容
        GUI_SetColor(GUI_BLUE);
        GUI_FillRect(0, 0, 20, 50);
        GUI_SetColor(GUI_GREEN);
      //  GUI_SetFont(&GUI_Font13_ASCII);
        GUI_DispStringHCenterAt("Child", 40, 35);

        GUI_MEMDEV_Handle hMemDev2 = GUI_MEMDEV_CreateFixed(90, 10, 80, 120, GUI_MEMDEV_NOTRANS, GUI_MEMDEV_APILIST_32, GUICC_8888);


        // 取消选择内存设备并将其内容复制到屏幕
        GUI_MEMDEV_Select(0);
        //GUI_MEMDEV_CopyToLCD(hMemDev);
        GUI_MEMDEV_Write(hMemDev);
        GUI_MEMDEV_Write(hMemDev2);
        // 删除内存设备
        GUI_MEMDEV_Delete(hMemDev);


        break;
    default:
        WM_DefaultProc(pMsg);
        break;
    }
}

// 父窗口回调函数
static void _cbParentWindow(WM_MESSAGE* pMsg) {
    WM_HWIN hChildWin;
    GUI_MEMDEV_Handle hMemDev;

    switch (pMsg->MsgId) {
    case WM_CREATE:
        // 创建子窗口，大小为 80x80，位于 (60, 60)
       // hChildWin = WM_CreateWindowAsChild(60, 60, 80, 80, pMsg->hWin, WM_CF_SHOW, _cbChildWindow, 0);
        hChildWin = WM_CreateWindowAsChild(10, 10, 80, 80, pMsg->hWin, WM_CF_SHOW | WM_CF_HASTRANS, _cbChildWindow, 0);
        break;

    case WM_PAINT:

        GUI_RECT Rect0;
        WM_GetClientRect(&Rect0);//这里是相对父类的坐标 （0,0,249,249）
        GUI_RECT Rect1;
        WM_GetWindowRect(&Rect1); //这里是相对屏幕的坐标  （30,30,279,279）

        GUI_RECT Rect2;
        WM_GetInsideRect(&Rect2);//这里得到的是父类的相对坐标，（0,0,249,249）

        // 创建一个 200x200 的内存设备
        hMemDev = GUI_MEMDEV_CreateFixed(0, 0, 200, 220, GUI_MEMDEV_NOTRANS, GUI_MEMDEV_APILIST_32, GUI_COLOR_CONV_8888);
        //hMemDev = GUI_MEMDEV_CreateFixed(0, 0, 200, 200, GUI_MEMDEV_NOTRANS, GUI_MEMDEV_APILIST_16, GUI_COLOR_CONV_565);
        //hMemDev = GUI_MEMDEV_Create(0, 0, 200, 200);
       // hMemDev = GUI_MEMDEV_CreateFixed(0, 0, 200, 200, 0, GUI_MEMDEV_APILIST_32, GUI_COLOR_CONV_8888);
        //hMemDev = GUI_MEMDEV_CreateFixed(0, 0, 200, 200, GUI_MEMDEV_HASTRANS, GUI_MEMDEV_APILIST_32, GUI_COLOR_CONV_8888);
        GUI_MEMDEV_Select(hMemDev);
        GUI_SetBkColor(GUI_DARKRED);
        GUI_Clear();
        // 在内存设备中绘制内容
        GUI_SetColor(GUI_GREEN);
        GUI_FillRect(0, 0, 200, 200);
        //GUI_SetColor(GUI_BLACK);
        GUI_SetColor(GUI_WHITE);
       // GUI_SetFont(&GUI_Font13_ASCII);
        GUI_DispStringHCenterAt("Parent", 100, 90);

        // 取消选择内存设备并将其内容复制到屏幕
        GUI_MEMDEV_Select(0);


        GUI_RECT Rect;
        WM_GetInsideRect(&Rect);
        GUI_SetColor(GUI_ORANGE);
        GUI_FillRect(Rect.x0, Rect.y0, Rect.x1, Rect.y1);

       //GUI_MEMDEV_CopyToLCD(hMemDev);
        GUI_MEMDEV_Write(hMemDev);

        // 删除内存设备
        GUI_MEMDEV_Delete(hMemDev);
        break;

    default:
        WM_DefaultProc(pMsg);
        break;
    }
}

void MainTask(void) {
    WM_HWIN hParentWin;

	// 初始化窗口管理
	//WM_SetCreateFlags(WM_CF_MEMDEV);

#if GUI_WINSUPPORT
//	WM_MULTIBUF_Enable(1);
#endif 
    // 初始化 emWin
    GUI_Init();

    // 创建父窗口，大小为 200x200，位于 (30, 30)
    hParentWin = WM_CreateWindow(30, 30, 250, 250, WM_CF_SHOW , _cbParentWindow, 0);

     //WM_CreateWindowAsChild(10, 10, 80, 80, hParentWin, WM_CF_SHOW| WM_CF_HASTRANS, _cbChildWindow, 0);
    //WM_InvalidateWindow(hParentWin);
    GUI_Exec();
    // GUI 主循环
    while (1) {
        GUI_Delay(100);
    }
}