2 \section{\class{wxDataViewModel
}}\label{wxdataviewmodel
}
4 wxDataViewModel is the base class for all data model to be
5 displayed by a
\helpref{wxDataViewCtrl
}{wxdataviewctrl
}.
6 All other models derive from it and must implement its
7 pure virtual functions in order to define a complete
8 data model. In detail, you need to override
9 \helpref{IsContainer
}{wxdataviewmodeliscontainer
},
10 \helpref{GetParent
}{wxdataviewmodelgetparent
},
11 \helpref{GetChildren
}{wxdataviewmodelgetchildren
},
12 \helpref{GetColumnCount
}{wxdataviewmodelgetcolumncount
},
13 \helpref{GetColumnType
}{wxdataviewmodelgetcolumntype
} and
14 \helpref{GetValue
}{wxdataviewmodelgetvalue
} in order to
15 define the data model which acts as an interface between
16 your actual data and the wxDataViewCtrl. Since you will
17 usually also allow the wxDataViewCtrl to change your data
18 through its graphical interface, you will also have to override
19 \helpref{SetValue
}{wxdataviewmodelsetvalue
} which the
20 wxDataViewCtrl will call when a change to some data has been
23 wxDataViewModel (as indeed the entire wxDataViewCtrl
24 code) is using
\helpref{wxVariant
}{wxvariant
} to store data and
25 its type in a generic way. wxVariant can be extended to contain
26 almost any data without changes to the original class.
28 The data that is presented through this data model is expected
29 to change at run-time. You need to inform the data model when
30 a change happened. Depending on what happened you need to call
31 one of the following methods:
32 \helpref{ValueChanged
}{wxdataviewmodelvaluechanged
},
33 \helpref{ItemAdded
}{wxdataviewmodelitemadded
},
34 \helpref{ItemDeleted
}{wxdataviewmodelitemdeleted
},
35 \helpref{ItemChanged
}{wxdataviewmodelitemchanged
},
36 \helpref{Cleared
}{wxdataviewmodelcleared
}.
38 Note that wxDataViewModel does not define the position or
39 index of any item in the control since several control might
40 display the data differently, but wxDataViewModel does
41 provide a
\helpref{Compare
}{wxdataviewmodelcompare
} method
42 which the wxDataViewCtrl may use to sort the data either
43 in conjunction with a column header or without (see
44 \helpref{HasDefaultCompare
}{wxdataviewmodelhasdefaultcompare
}.
46 This class maintains a list of
47 \helpref{wxDataViewModelNotifier
}{wxdataviewmodelnotifier
}
48 which link this class to the specific implementations on the
49 supported platforms so that e.g. calling
50 \helpref{ValueChanged
}{wxdataviewmodelvaluechanged
}
51 on this model will just call
52 \helpref{wxDataViewModelNotifier::ValueChanged
}{wxdataviewmodelnotifiervaluechanged
}
53 for each notifier that has been added. You can also add
54 your own notifier in order to get informed about any changes
55 to the data in the list model.
57 Currently wxWidgets provides the following models apart
59 \helpref{wxDataViewIndexListModel
}{wxdataviewindexlistmodel
}.
60 It is planned to add helper classes for simple tree
61 and list stores in the future.
63 \wxheading{Derived from
}
65 \helpref{wxObjectRefData
}{wxobjectrefdata
}
67 \wxheading{Include files
}
73 \helpref{wxAdv
}{librarieslist
}
77 \latexignore{\rtfignore{\wxheading{Members
}}}
79 \membersection{wxDataViewModel::wxDataViewModel
}\label{wxdataviewmodelwxdataviewmodel
}
81 \func{}{wxDataViewModel
}{\void}
85 \membersection{wxDataViewModel::
\destruct{wxDataViewModel
}}\label{wxdataviewmodeldtor
}
87 \func{}{\destruct{wxDataViewModel
}}{\void}
89 Destructor. This should not be called directly. Use DecRef() instead.
92 \membersection{wxDataViewModel::AddNotifier
}\label{wxdataviewmodeladdnotifier
}
94 \func{void
}{AddNotifier
}{\param{wxDataViewModelNotifier*
}{notifier
}}
96 Adds a
\helpref{wxDataViewModelNotifier
}{wxdataviewmodelnotifier
}
99 \membersection{wxDataViewModel::Cleared
}\label{wxdataviewmodelcleared
}
101 \func{virtual bool
}{Cleared
}{\void}
103 Called to inform the model that all data has been deleted.
105 \membersection{wxDataViewModel::Compare
}\label{wxdataviewmodelcompare
}
107 \func{virtual int
}{Compare
}{\param{const wxDataViewItem\&
}{item1
},
\param{const wxDataViewItem\&
}{item2
},
\param{unsigned int
}{column
},
\param{bool
}{ascending
}}
109 The compare function to be used by control. The default compare function
110 sorts by container and other items separately and in ascending order.
111 Override this for a different sorting behaviour.
113 See also
\helpref{HasDefaultCompare
}{wxdataviewmodelhasdefaultcompare
}.
115 \membersection{wxDataViewModel::GetColumnCount
}\label{wxdataviewmodelgetcolumncount
}
117 \constfunc{virtual unsigned int
}{GetColumnCount
}{\void}
119 Override this to indicate the number of columns in the model.
121 \membersection{wxDataViewModel::GetColumnType
}\label{wxdataviewmodelgetcolumntype
}
123 \constfunc{virtual wxString
}{GetColumnType
}{\param{unsigned int
}{col
}}
125 Override this to indicate what type of data is stored in the
126 column specified by
{\it col
}. This should return a string
127 indicating the type of data as reported by
\helpref{wxVariant
}{wxvariant
}.
129 \membersection{wxDataViewModel::GetChildren
}\label{wxdataviewmodelgetchildren
}
131 \constfunc{virtual unsigned int
}{GetChildren
}{\param{const wxDataViewItem\&
}{item
},
\param{wxDataViewItemArray\&
}{children
} }
133 Override this so the control can query the child items of
134 an item. Returns the number of items.
136 \membersection{wxDataViewModel::GetParent
}\label{wxdataviewmodelgetparent
}
138 \constfunc{virtual wxDataViewItem
}{GetParent
}{\param{const wxDataViewItem\&
}{item
}}
140 Override this to indicate which wxDataViewItem representing the parent
141 of
{\it item
} or an invalid wxDataViewItem if
{\it item
} is the root item.
143 \membersection{wxDataViewModel::GetValue
}\label{wxdataviewmodelgetvalue
}
145 \constfunc{virtual void
}{GetValue
}{\param{wxVariant\&
}{variant
},
\param{const wxDataViewItem\&
}{item
},
\param{unsigned int
}{col
}}
147 Override this to indicate the value of
{\it item
}
148 A
\helpref{wxVariant
}{wxvariant
} is used to store the data.
150 \membersection{wxDataViewModel::HasDefaultCompare
}\label{wxdataviewmodelhasdefaultcompare
}
152 \constfunc{virtual bool
}{HasDefaultCompare
}{\void}
154 Override this to indicate that the model provides a default compare
155 function that the control should use if no wxDataViewColumn has been
156 chosen for sorting. Usually, the user clicks on a column header for
157 sorting, the data will be sorted alphanumerically. If any other
158 order (e.g. by index or order of appearance) is required, then this
159 should be used. See also
\helpref{wxDataViewIndexListModel
}{wxdataviewindexlistmodel
}
160 for a model which makes use of this.
162 \membersection{wxDataViewModel::IsContainer
}\label{wxdataviewmodeliscontainer
}
164 \constfunc{virtual bool
}{IsContainer
}{\param{const wxDataViewItem\&
}{item
}}
166 Override this to indicate of
{\it item
} is a container, i.e. if
167 it can have child items.
169 \membersection{wxDataViewModel::ItemAdded
}\label{wxdataviewmodelitemadded
}
171 \func{virtual bool
}{ItemAdded
}{\param{const wxDataViewItem\&
}{parent
},
\param{const wxDataViewItem\&
}{item
}}
173 Call this to inform the model that an item has been added
176 \membersection{wxDataViewModel::ItemChanged
}\label{wxdataviewmodelitemchanged
}
178 \func{virtual bool
}{ItemChanged
}{\param{const wxDataViewItem\&
}{item
}}
180 Call this to inform the model that an item has changed.
182 This will eventually emit a wxEVT
\_DATAVIEW\_ITEM\_VALUE\_CHANGED
183 event (in which the column fields will not be set) to the user.
185 \membersection{wxDataViewModel::ItemsAdded
}\label{wxdataviewmodelitemsadded
}
187 \func{virtual bool
}{ItemsAdded
}{\param{const wxDataViewItem\&
}{parent
},
\param{const wxDataViewItemArray\&
}{items
}}
189 Call this to inform the model that several items have been added
192 \membersection{wxDataViewModel::ItemsChanged
}\label{wxdataviewmodelitemschanged
}
194 \func{virtual bool
}{ItemsChanged
}{\param{const wxDataViewItemArray\&
}{items
}}
196 Call this to inform the model that several items have changed.
198 This will eventually emit wxEVT
\_DATAVIEW\_ITEM\_VALUE\_CHANGED
199 events (in which the column fields will not be set) to the user.
201 \membersection{wxDataViewModel::ItemsDeleted
}\label{wxdataviewmodelitemsdeleted
}
203 \func{virtual bool
}{ItemsDeleted
}{\param{const wxDataViewItem\&
}{parent
},
\param{const wxDataViewItemArray\&
}{items
}}
205 Call this to inform the model that several items have been deleted.
207 \membersection{wxDataViewModel::RemoveNotifier
}\label{wxdataviewmodelremovenotifier
}
209 \func{void
}{RemoveNotifier
}{\param{wxDataViewModelNotifier*
}{notifier
}}
211 Remove the
{\it notifier
} from the list of notifiers.
213 \membersection{wxDataViewModel::Resort
}\label{wxdataviewmodelresort
}
215 \func{virtual void
}{Resort
}{\void}
217 Call this to initiate a resort after the sort function has
220 \membersection{wxDataViewModel::SetValue
}\label{wxdataviewmodelsetvalue
}
222 \func{virtual bool
}{SetValue
}{\param{const wxVariant\&
}{variant
},
\param{const wxDataViewItem\&
}{item
},
\param{unsigned int
}{col
}}
224 This gets called in order to set a value in the data model.
225 The most common scenario is that the wxDataViewCtrl calls
226 this method after the user changed some data in the view.
227 Afterwards
\helpref{ValueChanged
}{wxdataviewmodelvaluechanged
}
230 \membersection{wxDataViewModel::ValueChanged
}\label{wxdataviewmodelvaluechanged
}
232 \func{virtual bool
}{ValueChanged
}{\param{const wxDataViewItem\&
}{item
},
\param{unsigned int
}{col
}}
234 Call this to inform this model that a value in the model has
235 been changed. This is also called from wxDataViewCtrl's
236 internal editing code, e.g. when editing a text field
239 This will eventually emit a wxEVT
\_DATAVIEW\_ITEM\_VALUE\_CHANGED