Merge branch 'date-picker-blank'

Allow customizing text displayed in wxDatePickerCtrl without valid
value, notably not displaying anything in it in this case.

See https://github.com/wxWidgets/wxWidgets/pull/2109

include/wx/datetimectrl.h

@@ -32,6 +32,13 @@ public:
     // Set/get the date or time (in the latter case, time part is ignored).
     virtual void SetValue(const wxDateTime& dt) = 0;
     virtual wxDateTime GetValue() const = 0;
+
+    // For the controls with wxDP_ALLOWNONE style, set the string displayed
+    // when the control doesn't have any valid value. Currently this is only
+    // actually used under MSW, where it can be used to override the previous
+    // value which is still displayed by the control in this case, and ignored
+    // elsewhere.
+    virtual void SetNullText(const wxString& WXUNUSED(text)) { }
 };
 
 #if defined(__WXMSW__) && !defined(__WXUNIVERSAL__)

include/wx/generic/timectrl.h

@@ -13,11 +13,13 @@
 #include "wx/containr.h"
 #include "wx/compositewin.h"
 
+typedef wxTimePickerCtrlCommonBase<wxDateTimePickerCtrlBase> wxTimePickerCtrlGenericBase;
+
 class WXDLLIMPEXP_ADV wxTimePickerCtrlGeneric
-    : public wxCompositeWindow< wxNavigationEnabled<wxTimePickerCtrlBase> >
+    : public wxCompositeWindow< wxNavigationEnabled<wxTimePickerCtrlGenericBase> >
 {
 public:
-    typedef wxCompositeWindow< wxNavigationEnabled<wxTimePickerCtrlBase> > Base;
+    typedef wxCompositeWindow< wxNavigationEnabled<wxTimePickerCtrlGenericBase> > Base;
 
     // Creating the control.
     wxTimePickerCtrlGeneric() { Init(); }

include/wx/msw/datetimectrl.h

@@ -26,6 +26,8 @@ public:
     virtual void SetValue(const wxDateTime& dt) wxOVERRIDE;
     virtual wxDateTime GetValue() const wxOVERRIDE;
 
+    virtual void SetNullText(const wxString& text) wxOVERRIDE;
+
     // returns true if the platform should explicitly apply a theme border
     virtual bool CanApplyThemeBorder() const wxOVERRIDE { return false; }
 
@@ -46,43 +48,34 @@ protected:
                                  const wxValidator& validator,
                                  const wxString& name);
 
-    // Notice that the methods below must be overridden in all native MSW
-    // classes inheriting from this one but they can't be pure virtual because
-    // the generic implementations, not needing nor able to implement them, is
-    // also derived from this class currently. The real problem is, of course,
-    // this wrong class structure because the generic classes also inherit the
-    // wrong implementations of Set/GetValue() and DoGetBestSize() but as they
-    // override these methods anyhow, it does work -- but is definitely ugly
-    // and need to be changed (but how?) in the future.
-
 #if wxUSE_INTL
     // Override to return the date/time format used by this control.
-    virtual wxLocaleInfo MSWGetFormat() const /* = 0 */
-    {
-        wxFAIL_MSG( "Unreachable" );
-        return wxLOCALE_TIME_FMT;
-    }
+    virtual wxLocaleInfo MSWGetFormat() const = 0;
 #endif // wxUSE_INTL
 
     // Override to indicate whether we can have no date at all.
-    virtual bool MSWAllowsNone() const /* = 0 */
-    {
-        wxFAIL_MSG( "Unreachable" );
-        return false;
-    }
+    virtual bool MSWAllowsNone() const = 0;
 
     // Override to update m_date and send the event when the control contents
     // changes, return true if the event was handled.
-    virtual bool MSWOnDateTimeChange(const tagNMDATETIMECHANGE& dtch) /* = 0 */
-    {
-        wxUnusedVar(dtch);
-        wxFAIL_MSG( "Unreachable" );
-        return false;
-    }
+    virtual bool MSWOnDateTimeChange(const tagNMDATETIMECHANGE& dtch) = 0;
 
 
     // the date currently shown by the control, may be invalid
     wxDateTime m_date;
+
+private:
+    // Helper setting the appropriate format depending on the passed in state.
+    void MSWUpdateFormat(bool valid);
+
+    // Same thing, but only doing if the validity differs from the date
+    // validity, i.e. avoiding useless work if nothing needs to be done.
+    void MSWUpdateFormatIfNeeded(bool valid);
+
+
+    // shown when there is no valid value (so only used with wxDP_ALLOWNONE),
+    // always non-empty if SetNullText() was called, see the comments there
+    wxString m_nullText;
 };
 
 #endif // _WX_MSW_DATETIMECTRL_H_

include/wx/timectrl.h

@@ -29,7 +29,10 @@ enum
 // wxTimePickerCtrl: Allow the user to enter the time.
 // ----------------------------------------------------------------------------
 
-class WXDLLIMPEXP_ADV wxTimePickerCtrlBase : public wxDateTimePickerCtrl
+// The template argument must be a class deriving from wxDateTimePickerCtrlBase
+// (i.e. in practice either this class itself or wxDateTimePickerCtrl).
+template <typename Base>
+class wxTimePickerCtrlCommonBase : public Base
 {
 public:
     /*
@@ -67,7 +70,7 @@ public:
             return false;
         }
 
-        SetValue(dt);
+        this->SetValue(dt);
 
         return true;
     }
@@ -78,7 +81,7 @@ public:
         wxCHECK_MSG( hour && min && sec, false,
                      wxS("Time component pointers must be non-NULL") );
 
-        const wxDateTime::Tm tm = GetValue().GetTm();
+        const wxDateTime::Tm tm = this->GetValue().GetTm();
         *hour = tm.hour;
         *min = tm.min;
         *sec = tm.sec;
@@ -87,6 +90,10 @@ public:
     }
 };
 
+// This class is defined mostly for compatibility and is used as the base class
+// by native wxTimePickerCtrl implementations.
+typedef wxTimePickerCtrlCommonBase<wxDateTimePickerCtrl> wxTimePickerCtrlBase;
+
 #if defined(__WXMSW__) && !defined(__WXUNIVERSAL__)
     #include "wx/msw/timectrl.h"