Merge branch 'tlw-layout'

Make wxTLW::Layout() do the right thing and resize the only child to fit
the entire TLW client area.

See https://github.com/wxWidgets/wxWidgets/pull/1496

docs/doxygen/overviews/windowsizing.h

@@ -116,4 +116,9 @@ some simple explanations of things.
     the constraints algorithm is run. The @c Layout() method is what is called by
     the default @c EVT_SIZE handler for container windows.
 
+@li wxTopLevelWindow::Layout(): this overridden version does the same thing as
+    the base wxWindow::Layout() except, for convenience, it will also resize
+    the only child of the top-level window to cover its entire client area if
+    there is no sizer associated with the window. Note that this only happens
+    if there is exactly one child.
 */

include/wx/toplevel.h

@@ -276,9 +276,13 @@ public:
     virtual bool IsTopNavigationDomain(NavigationKind kind) const wxOVERRIDE;
     virtual bool IsVisible() const { return IsShown(); }
 
+    // override to do TLW-specific layout: we resize our unique child to fill
+    // the entire client area
+    virtual bool Layout() wxOVERRIDE;
+
     // event handlers
     void OnCloseWindow(wxCloseEvent& event);
-    void OnSize(wxSizeEvent& WXUNUSED(event)) { DoLayout(); }
+    void OnSize(wxSizeEvent& WXUNUSED(event)) { Layout(); }
 
     // Get rect to be used to center top-level children
     virtual void GetRectForTopLevelChildren(int *x, int *y, int *w, int *h);
@@ -326,9 +330,8 @@ protected:
     // send the iconize event, return true if processed
     bool SendIconizeEvent(bool iconized = true);
 
-    // do TLW-specific layout: we resize our unique child to fill the entire
-    // client area
-    void DoLayout();
+    // this method is only kept for compatibility, call Layout() instead.
+    void DoLayout() { Layout(); }
 
     static int WidthDefault(int w) { return w == wxDefaultCoord ? GetDefaultSize().x : w; }
     static int HeightDefault(int h) { return h == wxDefaultCoord ? GetDefaultSize().y : h; }

interface/wx/toplevel.h

@@ -283,8 +283,20 @@ public:
     bool IsUsingNativeDecorations() const;
 
     /**
-        See wxWindow::SetAutoLayout(): when auto layout is on, this function gets
-        called automatically when the window is resized.
+        Lays out the children using the window sizer or resizes the only child
+        of the window to cover its entire area.
+
+        This class overrides the base class Layout() method to check if this
+        window contains exactly one child -- which is commonly the case, with
+        wxPanel being often created as the only child of wxTopLevelWindow --
+        and, if this is the case, resizes this child window to cover the entire
+        client area.
+
+        Note that if you associate a sizer with this window, the sizer takes
+        precedence and the only-child-resizing is only used as fallback.
+
+        @returns @false if nothing was done because the window doesn't have
+                 neither a sizer nor a single child, @true otherwise.
     */
     virtual bool Layout();
 

interface/wx/window.h

@@ -3445,15 +3445,20 @@ public:
     void SetConstraints(wxLayoutConstraints* constraints);
 
     /**
-        Invokes the constraint-based layout algorithm or the sizer-based algorithm
-        for this window.
+        Lays out the children of this window using the associated sizer.
 
-        This function does not get called automatically when the window is resized
-        because lots of windows deriving from wxWindow does not need this functionality.
-        If you want to have Layout() called automatically, you should derive
-        from wxPanel (see wxPanel::Layout).
+        If a sizer hadn't been associated with this window (see SetSizer()),
+        this function doesn't do anything, unless this is a top level window
+        (see wxTopLevelWindow::Layout()).
+
+        Note that this method is called automatically when the window size
+        changes if it has the associated sizer (or if SetAutoLayout() with
+        @true argument had been explicitly called), ensuring that it is always
+        laid out correctly.
 
         @see @ref overview_windowsizing
+
+        @returns Always returns @true, the return value is not useful.
     */
     virtual bool Layout();
 

src/common/framecmn.cpp

@@ -465,7 +465,7 @@ void wxFrameBase::SetStatusBar(wxStatusBar *statBar)
     {
         PositionStatusBar();
 
-        DoLayout();
+        Layout();
     }
 }
 
@@ -597,19 +597,19 @@ void wxFrameBase::SetToolBar(wxToolBar *toolbar)
             m_frameToolBar = toolbar;
             PositionToolBar();
         }
-        //else: tricky: do not reset m_frameToolBar yet as otherwise DoLayout()
+        //else: tricky: do not reset m_frameToolBar yet as otherwise Layout()
         //      wouldn't recognize the (still existing) toolbar as one of our
         //      bars and wouldn't layout the single child of the frame correctly
 
 
-        // and this is even more tricky: we want DoLayout() to recognize the
+        // and this is even more tricky: we want Layout() to recognize the
         // old toolbar for the purpose of not counting it among our non-bar
         // children but we don't want to reserve any more space for it so we
         // temporarily hide it
         if ( m_frameToolBar )
             m_frameToolBar->Hide();
 
-        DoLayout();
+        Layout();
 
         if ( m_frameToolBar )
             m_frameToolBar->Show();

src/common/toplvcmn.cpp

@@ -411,20 +411,20 @@ bool wxTopLevelWindowBase::IsTopNavigationDomain(NavigationKind kind) const
 
 // default resizing behaviour - if only ONE subwindow, resize to fill the
 // whole client area
-void wxTopLevelWindowBase::DoLayout()
+bool wxTopLevelWindowBase::Layout()
 {
     // We are called during the window destruction several times, e.g. as
     // wxFrame tries to adjust to its tool/status bars disappearing. But
     // actually doing the layout is pretty useless in this case as the window
     // will disappear anyhow -- so just don't bother.
     if ( IsBeingDeleted() )
-        return;
+        return false;
 
 
     // if we're using constraints or sizers - do use them
     if ( GetAutoLayout() )
     {
-        Layout();
+        return wxNonOwnedWindow::Layout();
     }
     else
     {
@@ -443,7 +443,7 @@ void wxTopLevelWindowBase::DoLayout()
             {
                 if ( child )
                 {
-                    return;     // it's our second subwindow - nothing to do
+                    return false; // it's our second subwindow - nothing to do
                 }
 
                 child = win;
@@ -458,8 +458,12 @@ void wxTopLevelWindowBase::DoLayout()
             DoGetClientSize(&clientW, &clientH);
 
             child->SetSize(0, 0, clientW, clientH);
+
+            return true;
         }
     }
+
+    return false;
 }
 
 // The default implementation for the close window event.

src/generic/wizard.cpp

@@ -929,7 +929,7 @@ bool wxWizard::DoLayoutAdaptation()
     wxStandardDialogLayoutAdapter::DoFitWithScrolling(this, windows);
 
     // Size event doesn't get sent soon enough on wxGTK
-    DoLayout();
+    Layout();
 
     SetLayoutAdaptationDone(true);