interface/wx/headerctrl.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/headerctrl.h
   3 // Purpose:     interface of wxHeaderCtrl
   4 // Author:      Vadim Zeitlin
   5 // Created:     2008-12-01
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2008 Vadim Zeitlin <vadim@wxwidgets.org>
   8 // Licence:     wxWindows license
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 /**
  12     @class wxHeaderCtrl
  13
  14     wxHeaderCtrl is the control containing the column headings which is usually
  15     used for display of tabular data.
  16
  17     It is used as part of wxGrid and (will be used in the near future) in
  18     in wxDataViewCtrl and report view of wxListCtrl but can be also used
  19     independently. In general this class is meant to be used as part of another
  20     control which already stores the column information somewhere as it can't
  21     be used directly: instead you need to inherit from it and implement the
  22     GetColumn() method to provide column information. See wxHeaderCtrlSimple
  23     for a concrete control class which can be used directly.
  24
  25     In addition to labeling the columns, the control has the following
  26     features:
  27         - Column reordering support, either by explicitly configuring the
  28           columns order and calling SetColumnsOrder() or by dragging the
  29           columns interactively (if enabled).
  30         - Display of the icons in the header: this is often used to display a
  31           sort or reverse sort indicator when the column header is clicked.
  32
  33     Notice that this control itself doesn't do anything other than displaying
  34     the column headers. In particular column reordering and sorting must still
  35     be supported by the associated control displaying the real data under the
  36     header. Also remember to call ScrollWindow() method of the control if the
  37     associated data display window has a horizontal scrollbar, otherwise the
  38     headers wouldn't align with the data when the window is scrolled.
  39
  40     This control is implemented using the native header control under MSW
  41     systems and a generic implementation elsewhere.
  42
  43     @beginStyleTable
  44         @style{wxHD_DRAGDROP}
  45             If this style is specified (it is by default), the user can reorder
  46             the control columns by dragging them.
  47         @style{wxHD_DEFAULT_STYLE}
  48             Symbolic name for the default control style, currently equal to @c
  49             wxHD_DRAGDROP.
  50     @endStyleTable
  51
  52     @beginEventTable{wxHeaderCtrlEvent}
  53         @event{EVT_HEADER_CLICK(id, func)}
  54             A column heading was clicked.
  55         @event{EVT_HEADER_RIGHT_CLICK(id, func)}
  56             A column heading was right clicked.
  57         @event{EVT_HEADER_MIDDLE_CLICK(id, func)}
  58             A column heading was clicked with the middle mouse button.
  59
  60         @event{EVT_HEADER_DCLICK(id, func)}
  61             A column heading was double clicked.
  62         @event{EVT_HEADER_RIGHT_DCLICK(id, func)}
  63             A column heading was right double clicked.
  64         @event{EVT_HEADER_MIDDLE_DCLICK(id, func)}
  65             A column heading was double clicked with the middle mouse button.
  66
  67         @event{EVT_HEADER_SEPARATOR_DCLICK(id, func)}
  68             Separator to the right of the specified column was double clicked
  69             (this action is commonly used to resize the column to fit its
  70             contents width and the control provides UpdateColumnWidthToFit() method
  71             to make implementing this easier).
  72     @endEventTable
  73
  74     @library{wxcore}
  75     @category{ctrl}
  76
  77     @see wxGrid, wxListCtrl, wxDataViewCtrl
  78
  79
  80     @section headerctrl_improvements Future Improvements
  81
  82     Some features are supported by the native MSW control and so could be
  83     easily implemented in this version of wxHeaderCtrl but need to be
  84     implemented in the generic version as well to be really useful. Please let
  85     us know if you need or, better, plan to work on implementing, any of them:
  86         - Displaying bitmaps instead of or together with the text
  87         - Custom drawn headers
  88         - Filters associated with a column.
  89 */
  90 class wxHeaderCtrl
  91 {
  92 public:
  93     /**
  94         Default constructor not creating the underlying window.
  95
  96         You must use Create() after creating the object using this constructor.
  97      */
  98     wxHeaderCtrl();
  99
 100     /**
 101         Constructor creating the window.
 102
 103         Please see Create() for the parameters documentation.
 104      */
 105     wxHeaderCtrl(wxWindow *parent,
 106                  wxWindowID winid = wxID_ANY,
 107                  const wxPoint& pos = wxDefaultPosition,
 108                  const wxSize& size = wxDefaultSize,
 109                  long style = wxHD_DEFAULT_STYLE,
 110                  const wxString& name = wxHeaderCtrlNameStr);
 111
 112     /**
 113         Create the header control window.
 114
 115         @param parent
 116             The parent window. The header control should be typically
 117             positioned along the top edge of this window.
 118         @param winid
 119             Id of the control or @c wxID_ANY if you don't care.
 120         @param pos
 121             The initial position of the control.
 122         @param size
 123             The initial size of the control (usually not very useful as this
 124             control will typically be resized to have the same width as the
 125             associated data display control).
 126         @param style
 127             The control style, @c wxHD_DEFAULT_STYLE by default. Notice that
 128             the default style allows the user to reorder the columns by
 129             dragging them and you need to explicitly turn this feature off by
 130             using @code wxHD_DEFAULT_STYLE & ~wxHD_DRAGDROP @endcode if this is
 131             undesirable.
 132         @param name
 133             The name of the control.
 134      */
 135     bool Create(wxWindow *parent,
 136                 wxWindowID winid = wxID_ANY,
 137                 const wxPoint& pos = wxDefaultPosition,
 138                 const wxSize& size = wxDefaultSize,
 139                 long style = wxHD_DEFAULT_STYLE,
 140                 const wxString& name = wxHeaderCtrlNameStr);
 141
 142     /**
 143         Set the number of columns in the control.
 144
 145         The control will use GetColumn() to get information about all the
 146         new columns and refresh itself, i.e. this method also has the same
 147         effect as calling UpdateColumn() for all columns but it should only be
 148         used if the number of columns really changed.
 149      */
 150     void SetColumnCount(unsigned int count);
 151
 152     /**
 153         Return the number of columns in the control.
 154
 155         @return
 156             Number of columns as previously set by SetColumnCount().
 157
 158         @see IsEmpty()
 159      */
 160     unsigned int GetColumnCount() const;
 161
 162     /**
 163         Return whether the control has any columns.
 164
 165         @see GetColumnCount()
 166      */
 167     bool IsEmpty() const;
 168
 169 protected:
 170     /**
 171         Method to be implemented by the derived classes to return the
 172         information for the given column.
 173
 174         @param idx
 175             The column index, between 0 and the value last passed to
 176             SetColumnCount().
 177      */
 178     virtual wxHeaderColumnBase& GetColumn(unsigned int idx) = 0;
 179
 180     /**
 181         Method which may be implemented by the derived classes to allow double
 182         clicking the column separator to resize the column to fit its contents.
 183
 184         When a separator is double clicked, the default handler of
 185         EVT_HEADER_SEPARATOR_DCLICK event calls this function and refreshes the
 186         column if it returns @true so to implement the resizing of the column
 187         to fit its width on header double click you need to implement this
 188         method using logic similar to this example:
 189         @code
 190             class MyHeaderCtrl : public wxHeaderColumnBase
 191             {
 192             public:
 193                 ...
 194
 195                 void SetWidth(int width) { m_width = width; }
 196                 virtual int GetWidth() const { return m_width; }
 197
 198             private:
 199                 int m_width;
 200             };
 201
 202             class MyHeaderCtrl : public wxHeaderCtrl
 203             {
 204             public:
 205             protected:
 206                 virtual wxHeaderColumnBase& GetColumn(unsigned int idx)
 207                 {
 208                     return m_cols[idx];
 209                 }
 210
 211                 virtual bool UpdateColumnWidthToFit(unsigned int idx, int widthTitle)
 212                 {
 213                     int widthContents = ... compute minimal width for column idx ...
 214                     m_cols[idx].SetWidth(wxMax(widthContents, widthTitle));
 215                     return true;
 216                 }
 217
 218                 wxVector<MyHeaderColumn> m_cols;
 219             };
 220         @endcode
 221
 222         Base class version simply returns @false.
 223
 224         @param width
 225             Contains minimal width needed to display the column header itself
 226             and will usually be used as a starting point for the fitting width
 227             calculation.
 228         @return
 229             @true to indicate that the column was resized, i.e. GetColumn() now
 230             returns the new width value, and so must be refreshed or @false
 231             meaning that the control didn't reach to the separator double click.
 232      */
 233     virtual bool UpdateColumnWidthToFit(unsigned int idx, int widthTitle);
 234 };
 235
 236
 237 /**
 238     @class wxHeaderCtrlSimple
 239
 240     wxHeaderCtrlSimple is a concrete header control which can be used directly,
 241     without inheriting from it as you need to do when using wxHeaderCtrl
 242     itself.
 243
 244     When using it, you need to use simple AppendColumn(), InsertColumn() and
 245     DeleteColumn() methods instead of setting the number of columns with
 246     SetColumnCount() and returning the information about them from the
 247     overridden GetColumn().
 248
 249     @library{wxcore}
 250     @category{ctrl}
 251
 252     @see wxHeaderCtrl
 253 */
 254 class wxHeaderCtrlSimple : public wxHeaderCtrl
 255 {
 256 public:
 257     /**
 258         Default constructor not creating the underlying window.
 259
 260         You must use Create() after creating the object using this constructor.
 261      */
 262     wxHeaderCtrlSimple();
 263
 264     /**
 265         Constructor creating the window.
 266
 267         Please see the base class wxHeaderCtrl::Create() method for the
 268         parameters description.
 269      */
 270     wxHeaderCtrlSimple(wxWindow *parent,
 271                        wxWindowID winid = wxID_ANY,
 272                        const wxPoint& pos = wxDefaultPosition,
 273                        const wxSize& size = wxDefaultSize,
 274                        long style = wxHD_DEFAULT_STYLE,
 275                        const wxString& name = wxHeaderCtrlNameStr);
 276
 277     /**
 278         Insert the column at the given position.
 279
 280         @param col
 281             The column to insert. Notice that because of the existence of
 282             implicit conversion from wxString to wxHeaderColumn a string
 283             can be passed directly here.
 284         @param idx
 285             The position of the new column, from 0 to GetColumnCount(). Using
 286             GetColumnCount() means to append the column to the end.
 287
 288         @see AppendColumn()
 289      */
 290     void InsertColumn(const wxHeaderColumn& col, unsigned int idx);
 291
 292     /**
 293         Append the column to the end of the control.
 294
 295         @see InsertColumn()
 296      */
 297     void AppendColumn(const wxHeaderColumn& col);
 298
 299     /**
 300         Delete the column at the given position.
 301
 302         @see InsertColumn(), AppendColumn()
 303      */
 304     void DeleteColumn(unsigned int idx);
 305
 306     /**
 307         Show or hide the column.
 308
 309         Initially the column is shown by default or hidden if it was added with
 310         wxCOL_HIDDEN flag set.
 311
 312         When a column is hidden, it doesn't appear at all on the screen but its
 313         index is still taken into account when working with other columns. E.g.
 314         if there are three columns 0, 1 and 2 and the column 1 is hidden you
 315         still need to use index 2 to refer to the last visible column.
 316
 317         @param idx
 318             The index of the column to show or hide, from 0 to GetColumnCount().
 319         @param show
 320             Indicates whether the column should be shown (default) or hidden.
 321      */
 322     void ShowColumn(unsigned int idx, bool show = true);
 323
 324     /**
 325         Hide the column with the given index.
 326
 327         This is the same as calling @code ShowColumn(idx, false) @endcode.
 328
 329         @param idx
 330             The index of the column to show or hide, from 0 to GetColumnCount().
 331      */
 332     void HideColumn(unsigned int idx);
 333
 334     /**
 335         Update the column sort indicator.
 336
 337         The sort indicator, if shown, is typically an arrow pointing upwards or
 338         downwards depending on whether the control contents is sorted in
 339         ascending or descending order.
 340
 341         @param idx
 342             The column to set the sort indicator for.
 343         @param sortOrder
 344             If @true or @false show the sort indicator corresponding to
 345             ascending or descending sort order respectively, if @c -1 remove
 346             the currently shown sort indicator.
 347      */
 348     virtual void ShowSortIndicator(unsigned int idx, int sortOrder);
 349
 350     /**
 351         Remove the sort indicator from the given column.
 352
 353         This is the same as calling ShowSortIndicator() with @c -1 argument.
 354
 355         @param idx
 356             The column to remove sort indicator for.
 357      */
 358     void RemoveSortIndicator(unsigned int idx);
 359
 360 protected:
 361     /**
 362         This function can be overridden in the classes deriving from this
 363         control instead of overriding UpdateColumnWidthToFit().
 364
 365         To implement automatic column resizing to fit its contents width when
 366         the column divider is double clicked, you need to simply return the
 367         fitting width for the given column @a idx from this method, the control
 368         will automatically use the biggest value between the one returned from
 369         here and the one needed for the display of the column title itself.
 370
 371         The base class version returns -1 indicating that this function is not
 372         implemented.
 373      */
 374     virtual int GetBestFittingWidth(unsigned int idx) const;
 375 };
 376
 377 /**
 378     @class wxHeaderCtrlEvent
 379
 380     Event class representing the events generated by wxHeaderCtrl.
 381
 382     @library{wxcore}
 383     @category{ctrl}
 384
 385     @see wxHeaderCtrl
 386 */
 387 class wxHeaderCtrlEvent : public wxNotifyEvent
 388 {
 389 public:
 390     /**
 391         Return the index of the column affected by this event.
 392      */
 393     int GetColumn() const;
 394 };