Reposition the Disconnect dialog when work area dimensions change.

remoting/host/disconnect_window_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/host/disconnect_window.h"
 
 #include <windows.h>
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/win/scoped_gdi_object.h"
 #include "base/win/scoped_hdc.h"
 #include "base/win/scoped_select_object.h"
 #include "remoting/host/chromoting_host.h"
 #include "remoting/host/host_ui_resource.h"
 #include "remoting/host/ui_strings.h"
 
 // TODO(garykac): Lots of duplicated code in this file and
 // continue_window_win.cc. If we need to expand this then we should
 // create a class with the shared code.
 
 // HMODULE from DllMain/WinMain. This is needed to find our dialog resource.
 // This is defined in:
 //   Plugin: host_plugin.cc
 //   SimpleHost: simple_host_process.cc
 extern HMODULE g_hModule;
 
+namespace {
+
 const int DISCONNECT_HOTKEY_ID = 1000;
 const int kWindowBorderRadius = 14;
+const WCHAR kShellTrayWindowName[] = L"Shell_TrayWnd";

[alexeypa (please no reviews), 2012/08/10 17:28:02]

nit: WCHAR -> wchar_t. L"" gives a wide string, while WCHAR is UTF-16. 

[Wez, 2012/08/10 20:06:17]

Which are the same thing on Windows. ;)

[Wez, 2012/08/10 20:06:17]

Done.

[alexeypa (please no reviews), 2012/08/10 20:30:03]

Yeah, I know. It is messy.

+
+} // namespace anonymous
 
 namespace remoting {
 
 class DisconnectWindowWin : public DisconnectWindow {
  public:
   DisconnectWindowWin();
   virtual ~DisconnectWindowWin();
 
   virtual void Show(ChromotingHost* host,
                     const DisconnectCallback& disconnect_callback,
                     const std::string& username) OVERRIDE;
   virtual void Hide() OVERRIDE;
 
 private:
   static BOOL CALLBACK DialogProc(HWND hwmd, UINT msg, WPARAM wParam,
                                   LPARAM lParam);
 
   BOOL OnDialogMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
 
   void ShutdownHost();
   void EndDialog();
   void SetStrings(const UiStrings& strings, const std::string& username);
+  void SetDialogPosition();
 
   DisconnectCallback disconnect_callback_;
   HWND hwnd_;
   bool has_hotkey_;
   base::win::ScopedGDIObject<HPEN> border_pen_;
 
   DISALLOW_COPY_AND_ASSIGN(DisconnectWindowWin);
 };
 
 DisconnectWindowWin::DisconnectWindowWin()
@@ skipping 38 matching lines @@
           ShutdownHost();
           return TRUE;
       }
       return FALSE;
 
     // Ensure we don't try to use the HWND anymore.
     case WM_DESTROY:
       hwnd_ = NULL;
       return TRUE;
 
+    // Ensure the dialog stays visible if the work area dimensions change.
+    case WM_SETTINGCHANGE:
+      if (wParam == SPI_SETWORKAREA)
+        SetDialogPosition();
+      return TRUE;
+
+    // Ensure the dialog stays visible if the display dimensions change.
+    case WM_DISPLAYCHANGE:
+      SetDialogPosition();
+      return TRUE;
+
     // Handle the disconnect hot-key.
     case WM_HOTKEY:
       EndDialog();
       ShutdownHost();
       return TRUE;
 
     // Let the window be draggable by its client area by responding
     // that the entire window is the title bar.
     case WM_NCHITTEST:
       SetWindowLong(hwnd, DWL_MSGRESULT, HTCAPTION);
       return TRUE;
 
-    case WM_PAINT:
+    case WM_PAINT: {
+      PAINTSTRUCT ps;
+      HDC hdc = BeginPaint(hwnd_, &ps);
+      RECT rect;
+      GetClientRect(hwnd_, &rect);
       {
-        PAINTSTRUCT ps;
-        HDC hdc = BeginPaint(hwnd_, &ps);
-        RECT rect;
-        GetClientRect(hwnd_, &rect);
-        {
-          base::win::ScopedSelectObject border(hdc, border_pen_);
-          base::win::ScopedSelectObject brush(hdc, GetStockObject(NULL_BRUSH));
-          RoundRect(hdc, rect.left, rect.top, rect.right - 1, rect.bottom - 1,
-                    kWindowBorderRadius, kWindowBorderRadius);
-        }
-        EndPaint(hwnd_, &ps);
-        return TRUE;
+        base::win::ScopedSelectObject border(hdc, border_pen_);
+        base::win::ScopedSelectObject brush(hdc, GetStockObject(NULL_BRUSH));
+        RoundRect(hdc, rect.left, rect.top, rect.right - 1, rect.bottom - 1,
+                  kWindowBorderRadius, kWindowBorderRadius);
       }
+      EndPaint(hwnd_, &ps);
+      return TRUE;
+    }
   }
   return FALSE;
 }
 
 void DisconnectWindowWin::Show(ChromotingHost* host,
                                const DisconnectCallback& disconnect_callback,
                                const std::string& username) {
   CHECK(!hwnd_);
   disconnect_callback_ = disconnect_callback;
 
@@ skipping 26 matching lines @@
                                     (DLGPROC)DialogProc, (LPARAM)this);
   CHECK(hwnd_);
 
   // Set up handler for Ctrl-Alt-Esc shortcut.
   if (!has_hotkey_ && RegisterHotKey(hwnd_, DISCONNECT_HOTKEY_ID,
                                      MOD_ALT | MOD_CONTROL, VK_ESCAPE)) {
     has_hotkey_ = true;
   }
 
   SetStrings(host->ui_strings(), username);
-
-  // Try to center the window above the task-bar. If that fails, use the
-  // primary monitor. If that fails (very unlikely), use the default position.
-  HWND taskbar = FindWindow(L"Shell_TrayWnd", NULL);
-  HMONITOR monitor = MonitorFromWindow(taskbar, MONITOR_DEFAULTTOPRIMARY);
-  MONITORINFO monitor_info = {sizeof(monitor_info)};
-  RECT window_rect;
-  if (GetMonitorInfo(monitor, &monitor_info) &&
-      GetWindowRect(hwnd_, &window_rect)) {
-    int window_width = window_rect.right - window_rect.left;
-    int window_height = window_rect.bottom - window_rect.top;
-    int top = monitor_info.rcWork.bottom - window_height;
-    int left = (monitor_info.rcWork.right + monitor_info.rcWork.left -
-        window_width) / 2;
-    SetWindowPos(hwnd_, NULL, left, top, 0, 0, SWP_NOSIZE | SWP_NOZORDER);
-  }
+  SetDialogPosition();
   ShowWindow(hwnd_, SW_SHOW);
 }
 
 void DisconnectWindowWin::ShutdownHost() {
   CHECK(!disconnect_callback_.is_null());
   disconnect_callback_.Run();
 }
 
 static int GetControlTextWidth(HWND control) {
   RECT rect = {0, 0, 0, 0};
@@ skipping 55 matching lines @@
   GetWindowRect(hwnd_, &window_rect);
   int width = (window_rect.right - window_rect.left) +
       button_width_delta + label_width_delta;
   int height = window_rect.bottom - window_rect.top;
   SetWindowPos(hwnd_, NULL, 0, 0, width, height, SWP_NOMOVE|SWP_NOZORDER);
   HRGN rgn = CreateRoundRectRgn(0, 0, width, height, kWindowBorderRadius,
                                 kWindowBorderRadius);
   SetWindowRgn(hwnd_, rgn, TRUE);
 }
 
+void DisconnectWindowWin::SetDialogPosition() {
+  // Try to center the window above the task-bar. If that fails, use the
+  // primary monitor. If that fails (very unlikely), use the default position.
+  HWND taskbar = FindWindow(kShellTrayWindowName, NULL);
+  HMONITOR monitor = MonitorFromWindow(taskbar, MONITOR_DEFAULTTOPRIMARY);
+  MONITORINFO monitor_info = {sizeof(monitor_info)};
+  RECT window_rect;
+  if (GetMonitorInfo(monitor, &monitor_info) &&
+      GetWindowRect(hwnd_, &window_rect)) {
+    int window_width = window_rect.right - window_rect.left;
+    int window_height = window_rect.bottom - window_rect.top;
+    int top = monitor_info.rcWork.bottom - window_height;
+    int left = (monitor_info.rcWork.right + monitor_info.rcWork.left -
+        window_width) / 2;
+    SetWindowPos(hwnd_, NULL, left, top, 0, 0, SWP_NOSIZE | SWP_NOZORDER);
+  }
+}
+
 void DisconnectWindowWin::Hide() {
   EndDialog();
 }
 
 void DisconnectWindowWin::EndDialog() {
   if (has_hotkey_) {
     UnregisterHotKey(hwnd_, DISCONNECT_HOTKEY_ID);
     has_hotkey_ = false;
   }
 
   if (hwnd_) {
     ::DestroyWindow(hwnd_);
     hwnd_ = NULL;
   }
 }
 
 scoped_ptr<DisconnectWindow> DisconnectWindow::Create() {
   return scoped_ptr<DisconnectWindow>(new DisconnectWindowWin());
 }
 
 }  // namespace remoting