Added classes to manage simple tabular data of known structure using a

popup containing a wxGrid object.

BasePicker : Abstract class adding a popup to wxPickerBase  styled with
a wxTextCtrl.
BaseGridPicker : Abstract class adding a wxGrid in the popup.

JsonGridPickerCtrl : UI control storing the tabular data in a JSON
array.
LBoundJsonGridPicker : connect JsonGridPicker to database.
LGridJsonCellEditor : use LBoundJsonGridPicker in other wxGrid objects.
LGridJsonCellRenderer : render cell JSON data.

XmlGridPickerCtrl : UI control storing the tabular data in as XML
document.
LBoundXmlGridPicker : connect XmlGridPicker to database.
LGridXmlCellEditor : grid editor for LBoundXmlGridPicker.
LGridXmlCellRenderer : grid renderer for LBoundXmlGridPicker.

JsonHelper and XmlHelper : for applications to quickly get intent value
from database data..

The structure of managed tabular data :

Column 1 : Intent - this is what we want to store/edit. This can be
telephone numbers, email addresses, instant messaging addresses...
any single line piece of information that can exist many times for one
entity (person, company...).
Column 2 : Type - A short description of the intent : 'Home, Work,
Mobile, Fax, Other...'. It is displayed in a non editable wxComboBox.
Column 3 : Preferred - One line of data can be selected as the preferred
one. It is not mandatory, but it must be a single choice.
Column 4 : Notes - single line notes.

Adjust sql scripts and L7.dox.
Applied ANSI formatting style to all files.

Other changes :

Work around a nasty misbehavior.
Grid columns edited by a translated combobox expect full string
data as cell values. LResultSet::BEData() will report these mapped strings,
instead of database real data. LBoundComboBox::IsDirty() will always be
true even if the editor is unchanged once created.
Simplest workaround : disconnect m_BoundComboBox if unchanged.

LGridTextEditor::ProvideFormEditor() : set the form editor's value
explicitely.; wxTextCtrl does not interpret data it receives

LBoundControl::SetNull must be void.

LBoundGrid : Unbind:: instructions should limit to the widget's id, like Bind::

LConnection::GetReturnedKeys should return NULL.
LConnection::SetData should return void.

Notes : wxJSON must be configured with the same prefix as wxWidgets,
here /usr/local/{wxWidgets,wxWidgets-Release}.

L7/special/LGridXmlCellEditor.h

@@ -0,0 +1,123 @@
+/* 
+ * File:   LGridXmlCellEditor.h
+ * Author: SET - nmset@netcourrier.com
+ * License : LGPL version 2.1
+ * Copyright SET, M. D. - © 2014
+ *
+ * Created on December 15, 2019, 6:32 PM
+ */
+
+#ifndef LGRIDXMLCELLEDITOR_H
+#define LGRIDXMLCELLEDITOR_H
+
+#include "../LGridColEditor.h"
+#include "LBoundXmlGridPicker.h"
+
+class XmlGridEditorRsEVH;
+class LGridXmlCellEditor;
+
+/**
+ * A grid cell editor using LBoundXmlGridPicker
+ * @param newColName
+ * @param intentLabel
+ * @param types
+ * @param popupSize
+ */
+class LGridXmlCellEditor : public wxGridCellEditor, public LGridColEditor
+{
+    friend class XmlGridEditorRsEVH;
+public:
+    LGridXmlCellEditor(const wxString& newColName,
+                       const wxString& intentLabel,
+                       const wxArrayString& types,
+                       wxSize popupSize = wxDefaultSize);
+    virtual ~LGridXmlCellEditor();
+    /**
+     * Creates m_control as LBoundJsonGridPicker.
+     * @param parent
+     * @param id
+     * @param evtHandler
+     */
+    void Create(wxWindow *parent, wxWindowID id, wxEvtHandler *evtHandler);
+    /**
+     * Creates m_control if necessary. Registers the editor in the grid's resultset.
+     * @param row
+     * @param col
+     * @param grid
+     */
+    void BeginEdit(int row, int col, wxGrid *grid);
+    wxGridCellEditor* Clone() const;
+    bool EndEdit(int row, int col, const wxGrid *grid, const wxString &oldval, wxString *newval);
+    /**
+     * Applies the editor value as returned by GetValue() to the grid cell.
+     * @param row
+     * @param col
+     * @param grid
+     */
+    void ApplyEdit(int row, int col, wxGrid *grid);
+    /**
+     * Deletes the editor, all pointers to the editor are set to NULL.
+     */
+    void Reset();
+    /**
+     * 
+     * @return GetData(), or wxEmptyString if the editor control has not been created.
+     */
+    wxString GetValue() const;
+    /**
+     * Creates a wxTextCtrl to be used as editor in form view.
+     */
+    wxControl* ProvideFormEditor(wxWindow * parent);
+
+    wxControl* GetFormEditor() const
+    {
+        return m_formEditor;
+    }
+    /**
+     * Updates the grid cell and the editor. m_formEditor is deleted and set to NULL.
+     * @param row
+     * @param col
+     * @param grid
+     */
+    void SyncBack(const int row, const int col, wxGrid * grid);
+
+private:
+    wxString m_intentLabel;
+    wxArrayString m_choices;
+    wxSize m_popupSize;
+    XmlGridPickerCtrl * m_formEditor;
+    wxAny m_xmlBuffer;
+    int m_editRow;
+    /**
+     * Fully typed alias to m_control.
+     */
+    LBoundXmlGridPicker * m_BoundXmlGridPicker;
+    wxWeakRef<XmlGridEditorRsEVH> m_rsEVH;
+};
+
+/**
+ * Clears LGridXmlGridEditor::m_jsonBuffer on LBoundGrid::Cancel.
+ * Must be trackable. If it is deleted by an application, avoid crash in 
+ * destructor of LGridXmlGridEditor.
+ */
+class XmlGridEditorRsEVH : public LResultSetEvent, public wxTrackable
+{
+    friend class LGridXmlCellEditor;
+public:
+
+private:
+    XmlGridEditorRsEVH(LGridXmlCellEditor * owner);
+    virtual ~XmlGridEditorRsEVH();
+    virtual void AfterAction(LResultSet * caller, ACTIONS action);
+
+    void SetResultSet(LResultSet * caller)
+    {
+        m_rs = caller;
+    }
+
+    LResultSet * m_rs;
+    LGridXmlCellEditor * m_owner;
+};
+
+#endif /* LGRIDXMLCELLEDITOR_H */
+