Merge branch 'primary-display'

Handle the situation when primary display is not the first one.

See https://github.com/wxWidgets/wxWidgets/pull/1641

include/wx/display.h

@@ -42,12 +42,14 @@ class WXDLLIMPEXP_FWD_CORE wxDisplayImpl;
 class WXDLLIMPEXP_CORE wxDisplay
 {
 public:
+    // default ctor creates the object corresponding to the primary display
+    wxDisplay();
+
     // initialize the object containing all information about the given
     // display
     //
-    // the displays are numbered from 0 to GetCount() - 1, 0 is always the
-    // primary display and the only one which is always supported
-    wxDisplay(unsigned n = 0);
+    // the displays are numbered from 0 to GetCount() - 1
+    explicit wxDisplay(unsigned n);
 
     // create display object corresponding to the display of the given window
     // or the default one if the window display couldn't be found

include/wx/private/display.h

@@ -37,6 +37,9 @@ public:
         return m_impls[n];
     }
 
+    // Return the primary display object, creating it if necessary.
+    wxDisplayImpl* GetPrimaryDisplay();
+
     // get the total number of displays
     virtual unsigned GetCount() = 0;
 

interface/wx/display.h

@@ -16,6 +16,12 @@
 class wxDisplay
 {
 public:
+    /**
+        Default constructor creating wxDisplay object representing the primary
+        display.
+     */
+    wxDisplay();
+
     /**
         Constructor, setting up a wxDisplay instance with the specified
         display.
@@ -24,7 +30,7 @@ public:
             The index of the display to use. This must be non-negative and
             lower than the value returned by GetCount().
     */
-    wxDisplay(unsigned int index = 0);
+    explicit wxDisplay(unsigned int index);
 
     /**
         Constructor creating the display object associated with the given

samples/display/display.cpp

@@ -327,9 +327,7 @@ void MyFrame::PopuplateWithDisplayInfo()
         page->SetSizer(sizerTop);
         page->Layout();
 
-        m_book->AddPage(page,
-                        wxString::Format("Display %lu",
-                                         (unsigned long)nDpy));
+        m_book->AddPage(page, wxString::Format("Display %zu", nDpy + 1));
     }
 
     SetClientSize(m_book->GetBestSize());

src/common/dpycmn.cpp

@@ -77,6 +77,11 @@ wxIMPLEMENT_DYNAMIC_CLASS(wxDisplayModule, wxModule);
 // ctor/dtor
 // ----------------------------------------------------------------------------
 
+wxDisplay::wxDisplay()
+{
+    m_impl = Factory().GetPrimaryDisplay();
+}
+
 wxDisplay::wxDisplay(unsigned n)
 {
     wxASSERT_MSG( n == 0 || n < GetCount(),
@@ -89,7 +94,8 @@ wxDisplay::wxDisplay(const wxWindow* window)
 {
     const int n = GetFromWindow(window);
 
-    m_impl = Factory().GetDisplay(n != wxNOT_FOUND ? n : 0);
+    m_impl = n != wxNOT_FOUND ? Factory().GetDisplay(n)
+                              : Factory().GetPrimaryDisplay();
 }
 
 // ----------------------------------------------------------------------------
@@ -159,7 +165,7 @@ wxString wxDisplay::GetName() const
 
 bool wxDisplay::IsPrimary() const
 {
-    return m_impl && m_impl->GetIndex() == 0;
+    return m_impl && m_impl->IsPrimary();
 }
 
 #if wxUSE_DISPLAY
@@ -245,6 +251,24 @@ void wxDisplayFactory::ClearImpls()
     m_impls.clear();
 }
 
+wxDisplayImpl* wxDisplayFactory::GetPrimaryDisplay()
+{
+    // Just use dumb linear search -- there seems to be the most reliable way
+    // to do this in general. In particular, primary monitor is not guaranteed
+    // to be the first one and it's not obvious if it always contains (0, 0).
+    const unsigned count = GetCount();
+    for ( unsigned n = 0; n < count; ++n )
+    {
+        wxDisplayImpl* const d = GetDisplay(n);
+        if ( d && d->IsPrimary() )
+            return d;
+    }
+
+    // This is not supposed to happen, but what else can we do if it
+    // somehow does?
+    return NULL;
+}
+
 int wxDisplayFactory::GetFromWindow(const wxWindow *window)
 {
     wxCHECK_MSG( window, wxNOT_FOUND, "window can't be NULL" );

src/msw/display.cpp

@@ -111,9 +111,14 @@ namespace
 // Simple struct storing the information needed by wxDisplayMSW.
 struct wxDisplayInfo
 {
-    wxDisplayInfo(HMONITOR hmon_, int depth_) : hmon(hmon_), depth(depth_) {}
+    wxDisplayInfo(HMONITOR hmon_,
+                  const MONITORINFOEX& monInfo_,
+                  int depth_)
+        : hmon(hmon_), monInfo(monInfo_), depth(depth_)
+    {}
 
     HMONITOR hmon;
+    MONITORINFOEX monInfo;
     int depth;
 };
 
@@ -157,10 +162,6 @@ protected:
                            dm.dmDisplayFrequency > 1 ? dm.dmDisplayFrequency : 0);
     }
 
-    // Call GetMonitorInfo() and fill in the provided struct and return true if
-    // it succeeded, otherwise return false.
-    bool GetMonInfo(MONITORINFOEX& monInfo) const;
-
     wxDisplayInfo m_info;
 
 private:
@@ -298,37 +299,14 @@ wxDisplayFactoryMSW::GetDpiForMonitorData
 // wxDisplayMSW implementation
 // ----------------------------------------------------------------------------
 
-bool wxDisplayMSW::GetMonInfo(MONITORINFOEX& monInfo) const
-{
-    if ( !::GetMonitorInfo(m_info.hmon, &monInfo) )
-    {
-        wxLogLastError(wxT("GetMonitorInfo"));
-        return false;
-    }
-
-    return true;
-}
-
 wxRect wxDisplayMSW::GetGeometry() const
 {
-    WinStruct<MONITORINFOEX> monInfo;
-
-    wxRect rect;
-    if ( GetMonInfo(monInfo) )
-        wxCopyRECTToRect(monInfo.rcMonitor, rect);
-
-    return rect;
+    return wxRectFromRECT(m_info.monInfo.rcMonitor);
 }
 
 wxRect wxDisplayMSW::GetClientArea() const
 {
-    WinStruct<MONITORINFOEX> monInfo;
-
-    wxRect rectClient;
-    if ( GetMonInfo(monInfo) )
-        wxCopyRECTToRect(monInfo.rcWork, rectClient);
-
-    return rectClient;
+    return wxRectFromRECT(m_info.monInfo.rcWork);
 }
 
 int wxDisplayMSW::GetDepth() const
@@ -356,23 +334,12 @@ wxSize wxDisplayMSW::GetPPI() const
 
 wxString wxDisplayMSW::GetName() const
 {
-    WinStruct<MONITORINFOEX> monInfo;
-
-    wxString name;
-    if ( GetMonInfo(monInfo) )
-        name = monInfo.szDevice;
-
-    return name;
+    return m_info.monInfo.szDevice;
 }
 
 bool wxDisplayMSW::IsPrimary() const
 {
-    WinStruct<MONITORINFOEX> monInfo;
-
-    if ( !GetMonInfo(monInfo) )
-        return false;
-
-    return (monInfo.dwFlags & MONITORINFOF_PRIMARY) != 0;
+    return (m_info.monInfo.dwFlags & MONITORINFOF_PRIMARY) != 0;
 }
 
 wxVideoMode wxDisplayMSW::GetCurrentMode() const
@@ -623,7 +590,7 @@ wxDisplayFactoryMSW::MultimonEnumProc(
     const int hdcDepth = wxGetHDCDepth(hdcMonitor);
     ::DeleteDC(hdcMonitor);
 
-    self->m_displays.push_back(wxDisplayInfo(hMonitor, hdcDepth));
+    self->m_displays.push_back(wxDisplayInfo(hMonitor, monInfo, hdcDepth));
 
     // continue the enumeration
     return TRUE;