Add xcb test code

motif_app.cpp

@@ -1,12 +1,16 @@
 #include <QApplication>
 #include <QTimer>
+#include <QX11Info>
 #include "qt_dialog.h"
 
+#include <xcb/xcb.h>
+
 // Qt 头文件必须在 Motif/X11 之前
 #include <X11/Intrinsic.h>
 #include <Xm/Xm.h>
 #include <Xm/PushB.h>
 #include <unistd.h> // for usleep
+#include <iostream>
 
 // 全局 Qt 应用和对话框指针
 QApplication *g_app = nullptr;
@@ -16,7 +20,7 @@ void openQtDialog(Widget w, XtPointer client_data, XtPointer call_data)
 {
     auto dialog = new QtDialog();
     dialog->setAttribute(Qt::WA_DeleteOnClose); // 关闭时自动删除
-    dialog->show(); // 非阻塞显示
+    dialog->show();                             // 非阻塞显示
 }
 
 // Motif 主循环中处理 Qt 事件
@@ -36,6 +40,34 @@ int main(int argc, char **argv)
     // 创建 QApplication（必须在 Qt 头文件之后）
     g_app = new QApplication(argc, nullptr);
 
+    // int screen_num;
+    // xcb_connection_t *connection = xcb_connect(NULL, &screen_num);
+    xcb_connection_t *connection = QX11Info::connection();
+    // Qt 内部管理的 screen_num
+    int screen_num = QX11Info::appScreen();
+
+    if (xcb_connection_has_error(connection))
+    {
+        fprintf(stderr, "无法连接到 X 服务器\n");
+        return -1;
+    }
+
+    const xcb_setup_t *setup = xcb_get_setup(connection);
+    xcb_screen_iterator_t iter = xcb_setup_roots_iterator(setup);
+    for (int i = 0; i <= screen_num; i++)
+    {
+        xcb_screen_t *screen = iter.data;
+        xcb_screen_next(&iter);
+
+        printf("屏幕根窗口: %u, 尺寸: %dx%d\n",
+               screen->root, screen->width_in_pixels, screen->height_in_pixels);
+
+        std::cout << "screen_num: " << screen_num << std::endl;
+        std::cout << "screen root window: " << screen->root << std::endl;
+        std::cout << "screen size: " << screen->width_in_pixels
+                  << "x" << screen->height_in_pixels << std::endl;
+    }
+
     // 创建 Motif 主窗口
     toplevel = XtVaAppInitialize(&app_context, "MotifQtApp", NULL, 0,
                                  &argc, argv, NULL, NULL);
@@ -65,6 +97,7 @@ int main(int argc, char **argv)
 
     // 清理（一般不会执行到这里）
     delete g_app;
+    // xcb_disconnect(connection);
 
     return 0;
 }