Hand-code tab navigation from value field of Label Properties dialog.

wxWidgets doesn't appear to handle it correctly, doing nothing on OSX
and potentially crashing on GTK.

Fixes https://gitlab.com/kicad/code/kicad/issues/11572

eeschema/dialogs/dialog_label_properties.cpp

@@ -318,6 +318,33 @@ void DIALOG_LABEL_PROPERTIES::OnEnterKey( wxCommandEvent& aEvent )
 }
 
 
+void DIALOG_LABEL_PROPERTIES::OnValueCharHook( wxKeyEvent& aEvent )
+{
+    if( aEvent.GetKeyCode() == WXK_TAB )
+    {
+        if( aEvent.ShiftDown() )
+        {
+            m_textSizeCtrl->SetFocusFromKbd();
+        }
+        else
+         if( !m_fields->empty() )
+        {
+            m_grid->SetFocusFromKbd();
+            m_grid->MakeCellVisible( 0, 0 );
+            m_grid->SetGridCursor( 0, 0 );
+        }
+        else
+        {
+            m_textSizeCtrl->SetFocusFromKbd();
+        }
+    }
+    else
+    {
+        aEvent.Skip();
+    }
+}
+
+
 static bool positioningChanged( const SCH_FIELD& a, const SCH_FIELD& b )
 {
     if( a.GetPosition() != b.GetPosition() )

eeschema/dialogs/dialog_label_properties.h

@@ -42,6 +42,7 @@ public:
 
 private:
     void OnEnterKey( wxCommandEvent& aEvent ) override;
+    void OnValueCharHook( wxKeyEvent& aEvent ) override;
     void OnFormattingHelp( wxHyperlinkEvent& aEvent ) override;
 
     void onSpinButton( wxCommandEvent &aEvent );

eeschema/dialogs/dialog_label_properties_base.cpp

@@ -307,7 +307,9 @@ DIALOG_LABEL_PROPERTIES_BASE::DIALOG_LABEL_PROPERTIES_BASE( wxWindow* parent, wx
 
 	// Connect Events
 	this->Connect( wxEVT_UPDATE_UI, wxUpdateUIEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnUpdateUI ) );
+	m_valueSingleLine->Connect( wxEVT_CHAR_HOOK, wxKeyEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnValueCharHook ), NULL, this );
 	m_valueSingleLine->Connect( wxEVT_COMMAND_TEXT_ENTER, wxCommandEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnEnterKey ), NULL, this );
+	m_valueCombo->Connect( wxEVT_CHAR_HOOK, wxKeyEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnValueCharHook ), NULL, this );
 	m_valueCombo->Connect( wxEVT_COMMAND_TEXT_ENTER, wxCommandEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnEnterKey ), NULL, this );
 	m_syntaxHelp->Connect( wxEVT_COMMAND_HYPERLINK, wxHyperlinkEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnFormattingHelp ), NULL, this );
 	m_grid->Connect( wxEVT_SIZE, wxSizeEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnSizeGrid ), NULL, this );
@@ -321,7 +323,9 @@ DIALOG_LABEL_PROPERTIES_BASE::~DIALOG_LABEL_PROPERTIES_BASE()
 {
 	// Disconnect Events
 	this->Disconnect( wxEVT_UPDATE_UI, wxUpdateUIEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnUpdateUI ) );
+	m_valueSingleLine->Disconnect( wxEVT_CHAR_HOOK, wxKeyEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnValueCharHook ), NULL, this );
 	m_valueSingleLine->Disconnect( wxEVT_COMMAND_TEXT_ENTER, wxCommandEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnEnterKey ), NULL, this );
+	m_valueCombo->Disconnect( wxEVT_CHAR_HOOK, wxKeyEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnValueCharHook ), NULL, this );
 	m_valueCombo->Disconnect( wxEVT_COMMAND_TEXT_ENTER, wxCommandEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnEnterKey ), NULL, this );
 	m_syntaxHelp->Disconnect( wxEVT_COMMAND_HYPERLINK, wxHyperlinkEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnFormattingHelp ), NULL, this );
 	m_grid->Disconnect( wxEVT_SIZE, wxSizeEventHandler( DIALOG_LABEL_PROPERTIES_BASE::OnSizeGrid ), NULL, this );

eeschema/dialogs/dialog_label_properties_base.fbp

@@ -198,6 +198,7 @@
                                 <property name="window_extra_style"></property>
                                 <property name="window_name"></property>
                                 <property name="window_style"></property>
+                                <event name="OnCharHook">OnValueCharHook</event>
                                 <event name="OnTextEnter">OnEnterKey</event>
                             </object>
                         </object>
@@ -325,6 +326,7 @@
                                 <property name="window_extra_style"></property>
                                 <property name="window_name"></property>
                                 <property name="window_style"></property>
+                                <event name="OnCharHook">OnValueCharHook</event>
                                 <event name="OnTextEnter">OnEnterKey</event>
                             </object>
                         </object>

eeschema/dialogs/dialog_label_properties_base.h

@@ -98,6 +98,7 @@ class DIALOG_LABEL_PROPERTIES_BASE : public DIALOG_SHIM
 
 		// Virtual event handlers, overide them in your derived class
 		virtual void OnUpdateUI( wxUpdateUIEvent& event ) { event.Skip(); }
+		virtual void OnValueCharHook( wxKeyEvent& event ) { event.Skip(); }
 		virtual void OnEnterKey( wxCommandEvent& event ) { event.Skip(); }
 		virtual void OnFormattingHelp( wxHyperlinkEvent& event ) { event.Skip(); }
 		virtual void OnSizeGrid( wxSizeEvent& event ) { event.Skip(); }