fix: win, adjustNCCALCSIZE with monitor coords (#482)

* fix: win, adjustNCCALCSIZE with monitor coords

Signed-off-by: fufesou <[email protected]>

* #483

Signed-off-by: fufesou <[email protected]>

---------

Signed-off-by: fufesou <[email protected]>

Author: fufesou

windows/window_manager_plugin.cpp

@@ -62,9 +62,24 @@ class WindowManagerPlugin : public flutter::Plugin {
       const flutter::MethodCall<flutter::EncodableValue>& method_call,
       std::unique_ptr<flutter::MethodResult<flutter::EncodableValue>> result);
 
-  void adjustNCCALCSIZE(NCCALCSIZE_PARAMS* sz) {
-    LONG l = sz->rgrc[0].left;
-    LONG t = sz->rgrc[0].top;
+  void adjustNCCALCSIZE(HWND hwnd, NCCALCSIZE_PARAMS* sz) {
+    LONG l = 8;
+    LONG t = 8;
+
+    HMONITOR monitor = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);
+    if (monitor != NULL) {
+      MONITORINFO monitorInfo;
+      monitorInfo.cbSize = sizeof(MONITORINFO);
+      if (TRUE == GetMonitorInfo(monitor, &monitorInfo)) {
+        l = sz->rgrc[0].left - monitorInfo.rcWork.left;
+        t = sz->rgrc[0].top - monitorInfo.rcWork.top;
+      } else {
+        // GetMonitorInfo failed, use (8, 8) as default value
+      }
+    } else {
+      // unreachable code
+    }
+
     sz->rgrc[0].left -= l;
     sz->rgrc[0].top -= t;
     sz->rgrc[0].right += l;
@@ -105,7 +120,8 @@ WindowManagerPlugin::~WindowManagerPlugin() {
 }
 
 void WindowManagerPlugin::_EmitEvent(std::string eventName) {
-  if (channel == nullptr) return;
+  if (channel == nullptr)
+    return;
   flutter::EncodableMap args = flutter::EncodableMap();
   args[flutter::EncodableValue("eventName")] =
       flutter::EncodableValue(eventName);
@@ -128,15 +144,15 @@ std::optional<LRESULT> WindowManagerPlugin::HandleWindowProc(HWND hWnd,
     if (window_manager->IsFullScreen() &&
         window_manager->title_bar_style_ != "normal") {
       if (window_manager->is_frameless_) {
-        adjustNCCALCSIZE(reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam));
+        adjustNCCALCSIZE(hWnd, reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam));
       }
       return 0;
     }
     // This must always be before handling title_bar_style_ == "hidden" so
     // the `if TitleBarStyle.hidden` doesn't get executed.
     if (window_manager->is_frameless_) {
       if (window_manager->IsMaximized()) {
-        adjustNCCALCSIZE(reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam));
+        adjustNCCALCSIZE(hWnd, reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam));
       }
       return 0;
     }
@@ -145,12 +161,17 @@ std::optional<LRESULT> WindowManagerPlugin::HandleWindowProc(HWND hWnd,
     if (wParam && window_manager->title_bar_style_ == "hidden") {
       if (window_manager->IsMaximized()) {
         // Adjust the borders when maximized so the app isn't cut off
-        adjustNCCALCSIZE(reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam));
+        adjustNCCALCSIZE(hWnd, reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam));
       } else {
         NCCALCSIZE_PARAMS* sz = reinterpret_cast<NCCALCSIZE_PARAMS*>(lParam);
         // on windows 10, if set to 0, there's a white line at the top
         // of the app and I've yet to find a way to remove that.
         sz->rgrc[0].top += IsWindows11OrGreater() ? 0 : 1;
+        // The following lines are required for resizing the window.
+        // https://github.com/leanflutter/window_manager/issues/483
+        sz->rgrc[0].right -= 8;
+        sz->rgrc[0].bottom -= 8;
+        sz->rgrc[0].left -= -8;
       }
 
       // Previously (WVR_HREDRAW | WVR_VREDRAW), but returning 0 or 1 doesn't