RWindow::MessageBox

include/ReWindow/types/Window.h

@@ -200,7 +200,10 @@ public:
     /// Closes the window immediately, potentially without allowing finalization to occur.
     void ForceClose();
     void ForceCloseAndTerminateProgram();
-    void MessageBox(); // TODO: Must be implemented from scratch as a Motif Window in x11
+
+    /// Displays a small window with some text and an "OK" button.
+    /// @note Execution of the parent window is stopped while the message box is up.
+    void MessageBox(const std::string& title, const std::string& message);
 
     /// Sets whether or not to make the window fullscreen.
     /// @note This is implemented per-OS, and as such, it simply requests the OS to do what we want. No guarantee about follow-through can be given.

main.cpp

@@ -75,7 +75,7 @@ int main() {
     window->SetVsyncEnabled(true);
     window->SetResizable(true);
     window->SetCursorVisible(false);
-
+    window->MessageBox("MessageBox", "Generic message from a ReWindow MessageBox.");
 
 
 	Logger::Debug(std::format("Window '{}' flags: IN_FOCUS={} FULLSCREEN={} RESIZEABLE={} VSYNC={} QUIT={}",
@@ -89,7 +89,7 @@ int main() {
 
 	while (!window->IsClosing()) {
         window->ManagedRefresh();
-        window->Flash();
+        //window->Flash();
     }
     delete window;
 }

src/platform/linux/Window.cpp

@@ -58,6 +58,65 @@ void RWindow::Raise() {
     XRaiseWindow(platform->display, platform->window);
 }
 
+void RWindow::MessageBox(const std::string& window_title, const std::string& message) {
+    int padding = 10;
+
+    XFontStruct* font = XLoadQueryFont(platform->display, "6x13");
+    int text_width = XTextWidth(font, message.c_str(), message.size());
+    int button_text_width = XTextWidth(font, "OK", 2);
+    IPair button_size = {80, 30};
+    IPair dimensions = { std::max(text_width + 2 * padding, button_size.x + 2 * padding), 82};
+    IPair text_pos = {(dimensions.x - text_width) / 2, padding + font->ascent};
+    IPair button_pos = { (dimensions.x - button_size.x) / 2, text_pos.y + font->ascent + padding };
+
+    Window window = XCreateSimpleWindow(platform->display, RootWindow(platform->display, platform->defaultScreen),
+                                        100, 100, dimensions.x, dimensions.y, 1,
+                                        BlackPixel(platform->display, platform->defaultScreen),
+                                        WhitePixel(platform->display, platform->defaultScreen));
+
+    XStoreName(platform->display, window, window_title.c_str());
+    XSelectInput(platform->display, window, ExposureMask | ButtonPressMask);
+
+    // No resizing.
+    XSizeHints hints;
+    hints.flags = PMinSize | PMaxSize;
+    hints.min_width = hints.max_width = dimensions.x;
+    hints.min_height = hints.max_height = dimensions.y;
+    XSetWMNormalHints(platform->display, window, &hints);
+
+    XMapWindow(platform->display, window);
+    GC gc = XCreateGC(platform->display, window, 0, nullptr);
+    XSetForeground(platform->display, gc, BlackPixel(platform->display, platform->defaultScreen));
+
+
+    /* TODO positioning the window to be in the center of the parent window doesn't always work.
+    if (platform->window) {
+        XWindowAttributes parent_window_attributes;
+        XGetWindowAttributes(platform->display, platform->window, &parent_window_attributes);
+        XMoveWindow(platform->display, window, (parent_window_attributes.width - dimensions.x) / 2, (parent_window_attributes.height - dimensions.y) / 2);
+    }
+     */
+
+    XEvent event;
+    while (true) {
+        XNextEvent(platform->display, &event);
+
+        if (event.type == Expose) {
+            XDrawString(platform->display, window, gc, text_pos.x, text_pos.y, message.c_str(), message.size());
+            XDrawString(platform->display, window, gc, button_pos.x + (button_size.x - button_text_width) / 2, button_pos.y + 20, "OK", 2);
+            XDrawRectangle(platform->display, window, gc, button_pos.x, button_pos.y, button_size.x, button_size.y);
+        }
+
+        else if (event.type == ButtonPress)
+            if (event.xbutton.x >= button_pos.x && event.xbutton.x <= button_pos.x + button_size.x
+            && event.xbutton.y >= button_pos.y && event.xbutton.y <= button_pos.y + button_size.y)
+                break;
+    }
+
+    XFreeFont(platform->display, font);
+    XFreeGC(platform->display, gc);
+    XDestroyWindow(platform->display, window);
+}
 void RWindow::Lower()
 {
     Logger::Debug(std::format("Lowering window '{}'", this->title));
@@ -98,18 +157,14 @@ void RWindow::SetCursorVisible(bool cursor_enable) {
 void RWindow::SetResizable(bool sizable) {
     XGetWindowAttributes(platform->display, platform->window, &platform->windowAttributes);
 
-
     this->resizable = sizable;
-    if (!sizable)
-    {
+    if (!sizable) {
         Logger::Debug("Once you've done this you cannot make it resizable again.");
         platform->hints.flags = PMinSize | PMaxSize;
         platform->hints.min_width = platform->hints.max_width = platform->windowAttributes.width;
         platform->hints.min_height = platform->hints.max_height = platform->windowAttributes.height;
         XSetWMNormalHints(platform->display, platform->window, &platform->hints);
     }
-    //this->SetFlag(WindowFlag::RESIZABLE, resizable);
-
 }
 
 void RWindow::SetFlag(WindowFlag flag, bool state) {