Windows mobile: hide [X] button in task bar on unmaximize

When calling showNormal on a window that was maximized, we must remove
the [X] button from the task bar. But only if it was added by
qt_wince_maximize.

Task-number: QTBUG-8408
Reviewed-by: Martin Petersson
(cherry picked from commit ad4aff6e2d188d88a2c6b4b692932adb08491d22)

3 files changed, 19 insertions, 0 deletions

diff --git a/src/gui/kernel/qguifunctions_wince.cpp b/src/gui/kernel/qguifunctions_wince.cpp
index ab1a655..01ff3cd 100644
--- a/src/gui/kernel/qguifunctions_wince.cpp
+++ b/src/gui/kernel/qguifunctions_wince.cpp
@@ -76,6 +76,10 @@ struct AygSIPINFO
 #define SHIDIF_SIZEDLGFULLSCREEN 0x0004
 #endif
 
+#ifndef SHDB_HIDE
+#define SHDB_HIDE 0x0002
+#endif
+
 #ifndef SHFS_SHOWTASKBAR
 #define SHFS_SHOWTASKBAR 0x0001
 #endif
@@ -112,10 +116,12 @@ struct AygSIPINFO
 typedef BOOL (*AygInitDialog)(AygSHINITDLGINFO*);
 typedef BOOL (*AygFullScreen)(HWND, DWORD);
 typedef BOOL (*AygSHSipInfo)(UINT, UINT, PVOID, UINT);
+typedef BOOL (*AygSHDoneButton)(HWND, DWORD);
 
 static AygInitDialog ptrAygInitDialog = 0;
 static AygFullScreen ptrAygFullScreen = 0;
 static AygSHSipInfo  ptrAygSHSipInfo  = 0;
+static AygSHDoneButton ptrAygSHDoneButton = 0;
 static bool aygResolved = false;
 
 static void resolveAygLibs()
@@ -128,6 +134,7 @@ static void resolveAygLibs()
         ptrAygInitDialog = (AygInitDialog) ayglib.resolve("SHInitDialog");
         ptrAygFullScreen = (AygFullScreen) ayglib.resolve("SHFullScreen");
         ptrAygSHSipInfo  = (AygSHSipInfo)  ayglib.resolve("SHSipInfo");
+        ptrAygSHDoneButton = (AygSHDoneButton) ayglib.resolve("SHDoneButton");
     }
 }
 
@@ -336,6 +343,16 @@ void qt_wince_maximize(QWidget *widget)
     }
 }
 
+void qt_wince_unmaximize(QWidget *widget)
+{
+    if (ptrAygSHDoneButton && qt_wince_is_mobile()
+        && !(widget->windowFlags() & (Qt::WindowCancelButtonHint | Qt::WindowOkButtonHint)))
+    {
+        // Hide the [X] button, we've added in qt_wince_maximize.
+        ptrAygSHDoneButton(widget->winId(), SHDB_HIDE);
+    }
+}
+
 void qt_wince_minimize(HWND hwnd)
 {
 #ifdef Q_OS_WINCE_WM
diff --git a/src/gui/kernel/qwidget_win.cpp b/src/gui/kernel/qwidget_win.cpp
index 0f05c6b..23f57da 100644
--- a/src/gui/kernel/qwidget_win.cpp
+++ b/src/gui/kernel/qwidget_win.cpp
@@ -70,6 +70,7 @@
 #include "qguifunctions_wince.h"
 QT_USE_NAMESPACE
 extern void qt_wince_maximize(QWidget *widget);                          //defined in qguifunctions_wince.cpp
+extern void qt_wince_unmaximize(QWidget *widget);                        //defined in qguifunctions_wince.cpp
 extern void qt_wince_minimize(HWND hwnd);                                //defined in qguifunctions_wince.cpp
 extern void qt_wince_full_screen(HWND hwnd, bool fullScreen, UINT swpf); //defined in qguifunctions_wince.cpp
 extern bool qt_wince_is_mobile();                                        //defined in qguifunctions_wince.cpp
diff --git a/src/gui/kernel/qwidget_wince.cpp b/src/gui/kernel/qwidget_wince.cpp
index fc1e52c..76532ed 100644
--- a/src/gui/kernel/qwidget_wince.cpp
+++ b/src/gui/kernel/qwidget_wince.cpp
@@ -498,6 +498,7 @@ void QWidget::setWindowState(Qt::WindowStates newstate)
                 int style = GetWindowLong(internalWinId(), GWL_STYLE) | WS_BORDER | WS_POPUP | WS_CAPTION;
                 SetWindowLong(internalWinId(), GWL_STYLE, style);
                 SetWindowLong(internalWinId(), GWL_EXSTYLE, GetWindowLong (internalWinId(), GWL_EXSTYLE) & ~ WS_EX_NODRAG);
+                qt_wince_unmaximize(this);
             }
             if (isVisible() && newstate & Qt::WindowMaximized)
                 qt_wince_maximize(this);