FLTK 1.3.0
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A table of widgets or other content. More...
#include <Fl_Table.H>
Classes | |
class | IntVector |
Public Types | |
enum | TableContext { CONTEXT_NONE = 0, CONTEXT_STARTPAGE = 0x01, CONTEXT_ENDPAGE = 0x02, CONTEXT_ROW_HEADER = 0x04, CONTEXT_COL_HEADER = 0x08, CONTEXT_CELL = 0x10, CONTEXT_TABLE = 0x20, CONTEXT_RC_RESIZE = 0x40 } |
The context bit flags for Fl_Table related callbacks (eg. More... | |
Public Member Functions | |
void | add (Fl_Widget &w) |
The widget is removed from its current group (if any) and then added to the end of this group. | |
void | add (Fl_Widget *w) |
See void Fl_Group::add(Fl_Widget &w) | |
Fl_Widget *const * | array () |
void | begin () |
Sets the current group so you can build the widget tree by just constructing the widgets. | |
void | callback (Fl_Widget *, void *) |
Callbacks will be called depending on the setting of Fl_Widget::when(). | |
int | callback_col () |
Returns the current column the event occurred on. | |
TableContext | callback_context () |
Returns the current 'table context'. | |
int | callback_row () |
Returns the current row the event occurred on. | |
Fl_Widget * | child (int n) const |
Returns the child widget by an index. | |
int | children () const |
Returns the number of children in the table. | |
virtual void | clear () |
Clears the table to zero rows, zero columns. | |
int | col_header () |
Returns if column headers are enabled or not. | |
void | col_header (int flag) |
Enable or disable column headers. | |
void | col_header_color (Fl_Color val) |
Sets the color for column headers and redraws the table. | |
Fl_Color | col_header_color () |
Gets the color for column headers. | |
void | col_header_height (int height) |
Sets the height in pixels for column headers and redraws the table. | |
int | col_header_height () |
Gets the column header height. | |
void | col_position (int col) |
Sets the column scroll position to column 'col', and causes the screen to redraw. | |
int | col_position () |
Returns the current column scroll position as a column number. | |
int | col_resize () |
Returns the current value of this flag. | |
void | col_resize (int flag) |
Allows/disallows column resizing by the user. | |
int | col_resize_min () |
Sets the current column minimum resize value. | |
void | col_resize_min (int val) |
Returns the current column minimum resize value. | |
void | col_width (int col, int width) |
Sets the width of the specified column in pixels, and the table is redrawn. | |
int | col_width (int col) |
Returns the current width of the specified column in pixels. | |
void | col_width_all (int width) |
Convenience method to set the width of all columns to the same value, in pixels. | |
virtual void | cols (int val) |
Set the number of columns in the table and redraw. | |
int | cols () |
Get the number of columns in the table. | |
void | do_callback (TableContext context, int row, int col) |
void | draw (void) |
Draws the widget. | |
void | end () |
Exactly the same as current(this->parent()). | |
int | find (const Fl_Widget *w) const |
Searches the child array for the widget and returns the index. | |
int | find (const Fl_Widget &w) const |
See int Fl_Group::find(const Fl_Widget *w) const. | |
Fl_Table (int X, int Y, int W, int H, const char *l=0) | |
The constructor for the Fl_Table. | |
void | get_selection (int &row_top, int &col_left, int &row_bot, int &col_right) |
Gets the region of cells selected (highlighted). | |
void | init_sizes () |
Resets the internal array of widget sizes and positions. | |
void | insert (Fl_Widget &w, int n) |
The widget is removed from its current group (if any) and then inserted into this group. | |
void | insert (Fl_Widget &w, Fl_Widget *w2) |
This does insert(w, find(before)). | |
int | is_interactive_resize () |
Returns 1 if someone is interactively resizing a row or column. | |
int | is_selected (int r, int c) |
See if the cell at row r and column c is selected. | |
int | move_cursor (int R, int C) |
void | remove (Fl_Widget &w) |
Removes a widget from the group but does not delete it. | |
void | resize (int X, int Y, int W, int H) |
Changes the size of the Fl_Table, causing it to redraw. | |
int | row_header () |
Returns the value of this flag. | |
void | row_header (int flag) |
Enables/disables showing the row headers. | |
void | row_header_color (Fl_Color val) |
Sets the row header color and causes the screen to redraw. | |
Fl_Color | row_header_color () |
Returns the current row header color. | |
void | row_header_width (int width) |
Sets the row header width to n and causes the screen to redraw. | |
int | row_header_width () |
Returns the current row header width (in pixels). | |
void | row_height (int row, int height) |
Sets the height of the specified row in pixels, and the table is redrawn. | |
int | row_height (int row) |
Returns the current height of the specified row as a value in pixels. | |
void | row_height_all (int height) |
Convenience method to set the height of all rows to the same value, in pixels. | |
void | row_position (int row) |
Sets the row scroll position to 'row', and causes the screen to redraw. | |
int | row_position () |
Returns the current row scroll position as a row number. | |
int | row_resize () |
Returns the current value of this flag. | |
void | row_resize (int flag) |
Allows/disallows row resizing by the user. | |
int | row_resize_min () |
Returns the current row minimum resize value. | |
void | row_resize_min (int val) |
Sets the current row minimum resize value. | |
virtual void | rows (int val) |
Sets the number of rows in the table, and the table is redrawn. | |
int | rows () |
Returns the number of rows in the table. | |
void | set_selection (int row_top, int col_left, int row_bot, int col_right) |
Sets the region of cells to be selected (highlighted). | |
void | table_box (Fl_Boxtype val) |
Sets the kind of box drawn around the data table, the default being FL_NO_BOX. | |
Fl_Boxtype | table_box (void) |
Returns the current box type used for the data table. | |
void | top_row (int row) |
Sets which row should be at the top of the table, scrolling as necessary, and the table is redrawn. | |
int | top_row () |
Returns the current top row shown in the table. | |
void | visible_cells (int &r1, int &r2, int &c1, int &c2) |
Returns the range of row and column numbers for all visible and partially visible cells in the table. | |
void | when (Fl_When flags) |
The Fl_Widget::when() function is used to set a group of flags, determining when the widget callback is called: | |
~Fl_Table () | |
The destructor for the Fl_Table. | |
Protected Types | |
enum | ResizeFlag { RESIZE_NONE = 0, RESIZE_COL_LEFT = 1, RESIZE_COL_RIGHT = 2, RESIZE_ROW_ABOVE = 3, RESIZE_ROW_BELOW = 4 } |
Protected Member Functions | |
void | change_cursor (Fl_Cursor newcursor) |
long | col_scroll_position (int col) |
TableContext | cursor2rowcol (int &R, int &C, ResizeFlag &resizeflag) |
void | damage_zone (int r1, int c1, int r2, int c2, int r3=0, int c3=0) |
virtual void | draw_cell (TableContext context, int R=0, int C=0, int X=0, int Y=0, int W=0, int H=0) |
Subclass should override this method to handle drawing the cells. | |
int | find_cell (TableContext context, int R, int C, int &X, int &Y, int &W, int &H) |
void | get_bounds (TableContext context, int &X, int &Y, int &W, int &H) |
int | handle (int e) |
Handles the specified event. | |
int | is_fltk_container () |
void | recalc_dimensions () |
void | redraw_range (int toprow, int botrow, int leftcol, int rightcol) |
int | row_col_clamp (TableContext context, int &R, int &C) |
long | row_scroll_position (int row) |
void | table_resized () |
void | table_scrolled () |
Static Protected Member Functions | |
static void | scroll_cb (Fl_Widget *, void *) |
Protected Attributes | |
int | botrow |
int | current_col |
int | current_row |
Fl_Scrollbar * | hscrollbar |
int | leftcol |
int | leftcol_scrollpos |
int | rightcol |
int | select_col |
int | select_row |
Fl_Scroll * | table |
int | table_h |
int | table_w |
int | tih |
int | tiw |
int | tix |
int | tiy |
int | toh |
int | toprow |
int | toprow_scrollpos |
int | tow |
int | tox |
int | toy |
Fl_Scrollbar * | vscrollbar |
int | wih |
int | wiw |
int | wix |
int | wiy |
A table of widgets or other content.
This is the base class for table widgets.
To be useful it must be subclassed and several virtual functions defined. Normally applications use widgets derived from this widget, and do not use this widget directly; this widget is usually too low level to be used directly by applications.
This widget does not handle the data in the table. The draw_cell() method must be overridden by a subclass to manage drawing the contents of the cells.
This widget can be used in several ways:
When acting as part of a custom widget, events on the cells and/or headings generate callbacks when they are clicked by the user. You control when events are generated based on the setting for Fl_Table::when().
When acting as a container for FLTK widgets, the FLTK widgets maintain themselves. Although the draw_cell() method must be overridden, its contents can be very simple. See the draw_cell() code in examples/table-simple.cxx.
The following variables are available to classes deriving from Fl_Table:
x()/y()/w()/h() | Fl_Table widget's outer dimension. The outer edge of the border of the Fl_Table. (Red in the diagram above) |
wix/wiy/wiw/wih | Fl_Table widget's inner dimension. The inner edge of the border of the Fl_Table. eg. if the Fl_Table's box() is FL_NO_BOX, these values are the same as x()/y()/w()/h(). (Yellow in the diagram above) |
tox/toy/tow/toh | The table's outer dimension. The outer edge of the border around the cells, but inside the row/col headings and scrollbars. (Green in the diagram above) |
tix/tiy/tiw/tih | The table's inner dimension. The inner edge of the border around the cells, but inside the row/col headings and scrollbars. AKA the table's clip region. eg. if the table_box() is FL_NO_BOX, these values are the same as tox/toyy/tow/toh. (Blue in the diagram above) |
CORE DEVELOPERS
OTHER CONTRIBUTORS
LICENSE
Greg added the following license to the original distribution of Fl_Table. He kindly gave his permission to integrate Fl_Table and Fl_Table_Row into FLTK, allowing FLTK license to apply while his widgets are part of the library.
If used on its own, this is the license that applies:
Fl_Table License December 16, 2002 The Fl_Table library and included programs are provided under the terms of the GNU Library General Public License (LGPL) with the following exceptions: 1. Modifications to the Fl_Table configure script, config header file, and makefiles by themselves to support a specific platform do not constitute a modified or derivative work. The authors do request that such modifications be contributed to the Fl_Table project - send all contributions to "erco at seriss dot com". 2. Widgets that are subclassed from Fl_Table widgets do not constitute a derivative work. 3. Static linking of applications and widgets to the Fl_Table library does not constitute a derivative work and does not require the author to provide source code for the application or widget, use the shared Fl_Table libraries, or link their applications or widgets against a user-supplied version of Fl_Table. If you link the application or widget to a modified version of Fl_Table, then the changes to Fl_Table must be provided under the terms of the LGPL in sections 1, 2, and 4. 4. You do not have to provide a copy of the Fl_Table license with programs that are linked to the Fl_Table library, nor do you have to identify the Fl_Table license in your program or documentation as required by section 6 of the LGPL. However, programs must still identify their use of Fl_Table. The following example statement can be included in user documentation to satisfy this requirement: [program/widget] is based in part on the work of the Fl_Table project http://seriss.com/people/erco/fltk/Fl_Table/
The context bit flags for Fl_Table related callbacks (eg.
draw_cell(), callback(), etc)
Fl_Table::Fl_Table | ( | int | X, |
int | Y, | ||
int | W, | ||
int | H, | ||
const char * | l = 0 |
||
) |
The constructor for the Fl_Table.
This creates an empty table with no rows or columns, with headers and row/column resize behavior disabled.
Fl_Table::~Fl_Table | ( | ) |
The destructor for the Fl_Table.
Destroys the table and its associated widgets.
void Fl_Table::begin | ( | ) | [inline] |
Sets the current group so you can build the widget tree by just constructing the widgets.
begin() is automatically called by the constructor for Fl_Group (and thus for Fl_Window as well). begin() is exactly the same as current(this). Don't forget to end() the group or window!
Reimplemented from Fl_Group.
void Fl_Table::callback | ( | Fl_Widget * | , |
void * | |||
) |
Callbacks will be called depending on the setting of Fl_Widget::when().
Callback functions should use the following functions to determine the context/row/column:
Fl_Table::callback_row() returns current row Fl_Table::callback_col() returns current column Fl_Table::callback_context() returns current table context
callback_row() and callback_col() will be set to the row and column number the event occurred on. If someone clicked on a row header, col
will be 0. If someone clicked on a column header, row
will be 0.
callback_context() will return one of the following:
Fl_Table::CONTEXT_ROW_HEADER | Someone clicked on a row header. Excludes resizing. |
Fl_Table::CONTEXT_COL_HEADER | Someone clicked on a column header. Excludes resizing. |
Fl_Table::CONTEXT_CELL | Someone clicked on a cell. To receive callbacks for FL_RELEASE events, you must set when(FL_WHEN_RELEASE). |
Fl_Table::CONTEXT_RC_RESIZE | Someone is resizing rows/columns either interactively, or via the col_width() or row_height() API. Use is_interactive_resize() to determine interactive resizing. If resizing a column, R=0 and C=column being resized. If resizing a row, C=0 and R=row being resized. NOTE: To receive resize events, you must set when(FL_WHEN_CHANGED). |
class MyTable : public Fl_Table { [..] private: // Handle events that happen on the table void event_callback2() { int R = callback_row(), // row where event occurred C = callback_col(); // column where event occurred TableContext context = callback_context(); // which part of table fprintf(stderr, "callback: Row=%d Col=%d Context=%d Event=%d\n", R, C, (int)context, (int)Fl::event()); } // Actual static callback static void event_callback(Fl_Widget*, void* data) { MyTable *o = (MyTable*)data; o->event_callback2(); } public: // Constructor MyTable() { [..] table.callback(&event_callback, (void*)this); // setup callback table.when(FL_WHEN_CHANGED|FL_WHEN_RELEASE); // when to call it } };
int Fl_Table::callback_col | ( | ) | [inline] |
Returns the current column the event occurred on.
This function should only be used from within the user's callback function
TableContext Fl_Table::callback_context | ( | ) | [inline] |
Returns the current 'table context'.
This function should only be used from within the user's callback function
int Fl_Table::callback_row | ( | ) | [inline] |
Returns the current row the event occurred on.
This function should only be used from within the user's callback function
Fl_Widget* Fl_Table::child | ( | int | n | ) | const [inline] |
int Fl_Table::children | ( | ) | const [inline] |
virtual void Fl_Table::clear | ( | ) | [inline, virtual] |
Clears the table to zero rows, zero columns.
Same as rows(0); cols(0);
Reimplemented from Fl_Group.
Reimplemented in Fl_Table_Row.
void Fl_Table::col_header | ( | int | flag | ) | [inline] |
Enable or disable column headers.
If changed, the table is redrawn.
void Fl_Table::col_resize | ( | int | flag | ) | [inline] |
Allows/disallows column resizing by the user.
1=allow interactive resizing, 0=disallow interactive resizing. Since interactive resizing is done via the column headers, col_header()
must also be enabled to allow resizing.
int Fl_Table::col_resize_min | ( | ) | [inline] |
Sets the current column minimum resize value.
This is used to prevent the user from interactively resizing any column to be smaller than 'pixels'. Must be a value >=1.
void Fl_Table::col_width | ( | int | col, |
int | width | ||
) |
Sets the width of the specified column in pixels, and the table is redrawn.
callback() will be invoked with CONTEXT_RC_RESIZE if the column's width was actually changed, and when() is FL_WHEN_CHANGED.
void Fl_Table::col_width_all | ( | int | width | ) | [inline] |
Convenience method to set the width of all columns to the same value, in pixels.
The screen is redrawn.
void Fl_Table::draw | ( | void | ) | [virtual] |
Draws the widget.
Never call this function directly. FLTK will schedule redrawing whenever needed. If your widget must be redrawn as soon as possible, call redraw() instead.
Override this function to draw your own widgets.
If you ever need to call another widget's draw method from within your own draw() method, e.g. for an embedded scrollbar, you can do it (because draw() is virtual) like this:
Fl_Widget *s = &scroll; // scroll is an embedded Fl_Scrollbar s->draw(); // calls Fl_Scrollbar::draw()
Reimplemented from Fl_Group.
virtual void Fl_Table::draw_cell | ( | TableContext | context, |
int | R = 0 , |
||
int | C = 0 , |
||
int | X = 0 , |
||
int | Y = 0 , |
||
int | W = 0 , |
||
int | H = 0 |
||
) | [inline, protected, virtual] |
Subclass should override this method to handle drawing the cells.
This method will be called whenever the table is redrawn, once per cell.
Only cells that are completely (or partially) visible will be told to draw.
context
will be one of the following:
Fl_Table::CONTEXT_STARTPAGE | When table, or parts of the table, are about to be redrawn. R/C will be zero, |
Fl_Table::CONTEXT_ENDPAGE | When table has completed being redrawn. R/C will be zero, X/Y/W/H dimensions of table's data area. (Useful for unlocking a database after accessing) |
Fl_Table::CONTEXT_ROW_HEADER | Whenever a row header cell needs to be drawn. R will be the row number of the header being redrawn, C will be zero, X/Y/W/H will be the fltk drawing area of the row header in the window |
Fl_Table::CONTEXT_COL_HEADER | Whenever a column header cell needs to be drawn. R will be zero, C will be the column number of the header being redrawn, X/Y/W/H will be the fltk drawing area of the column header in the window |
Fl_Table::CONTEXT_CELL | Whenever a data cell in the table needs to be drawn. R/C will be the row/column of the cell to be drawn, X/Y/W/H will be the fltk drawing area of the cell in the window |
Fl_Table::CONTEXT_RC_RESIZE | Whenever table or row/column is resized or scrolled, either interactively or via col_width() or row_height(). Useful for fltk containers that need to resize or move the child fltk widgets. |
row
and col
will be set to the row and column number of the cell being drawn. In the case of row headers, col
will be 0. In the case of column headers, row
will be 0.
x/y/w/h
will be the position and dimensions of where the cell should be drawn.
In the case of custom widgets, a minimal draw_cell() override might look like the following. With custom widgets it is up to the caller to handle drawing everything within the dimensions of the cell, including handling the selection color. Note all clipping must be handled as well; this allows drawing outside the dimensions of the cell if so desired for 'custom effects'.
// This is called whenever Fl_Table wants you to draw a cell void MyTable::draw_cell(TableContext context, int R=0, int C=0, int X=0, int Y=0, int W=0, int H=0) { static char s[40]; sprintf(s, "%d/%d", R, C); // text for each cell switch ( context ) { case CONTEXT_STARTPAGE: // Fl_Table telling us its starting to draw page fl_font(FL_HELVETICA, 16); return; case CONTEXT_ROW_HEADER: // Fl_Table telling us it's draw row/col headers case CONTEXT_COL_HEADER: fl_push_clip(X, Y, W, H); { fl_draw_box(FL_THIN_UP_BOX, X, Y, W, H, color()); fl_color(FL_BLACK); fl_draw(s, X, Y, W, H, FL_ALIGN_CENTER); } fl_pop_clip(); return; case CONTEXT_CELL: // Fl_Table telling us to draw cells fl_push_clip(X, Y, W, H); { // BG COLOR fl_color( row_selected(R) ? selection_color() : FL_WHITE); fl_rectf(X, Y, W, H); // TEXT fl_color(FL_BLACK); fl_draw(s, X, Y, W, H, FL_ALIGN_CENTER); // BORDER fl_color(FL_LIGHT2); fl_rect(X, Y, W, H); } fl_pop_clip(); return; default: return; } //NOTREACHED }
void Fl_Table::end | ( | ) | [inline] |
int Fl_Table::find | ( | const Fl_Widget * | o | ) | const [inline] |
Searches the child array for the widget and returns the index.
Returns children() if the widget is NULL or not found.
Reimplemented from Fl_Group.
void Fl_Table::get_selection | ( | int & | row_top, |
int & | col_left, | ||
int & | row_bot, | ||
int & | col_right | ||
) |
Gets the region of cells selected (highlighted).
[in] | row_top | Returns the top row of selection area |
[in] | col_left | Returns the left column of selection area |
[in] | row_bot | Returns the bottom row of selection area |
[in] | col_right | Returns the right column of selection area |
int Fl_Table::handle | ( | int | event | ) | [protected, virtual] |
Handles the specified event.
You normally don't call this method directly, but instead let FLTK do it when the user interacts with the widget.
When implemented in a widget, this function must return 0 if the widget does not use the event or 1 otherwise.
Most of the time, you want to call the inherited handle() method in your overridden method so that you don't short-circuit events that you don't handle. In this last case you should return the callee retval.
[in] | event | the kind of event received |
0 | if the event was not used or understood |
1 | if the event was used and can be deleted |
Reimplemented from Fl_Group.
Reimplemented in Fl_Table_Row.
void Fl_Table::init_sizes | ( | ) | [inline] |
Resets the internal array of widget sizes and positions.
The Fl_Group widget keeps track of the original widget sizes and positions when resizing occurs so that if you resize a window back to its original size the widgets will be in the correct places. If you rearrange the widgets in your group, call this method to register the new arrangement with the Fl_Group that contains them.
If you add or remove widgets, this will be done automatically.
Reimplemented from Fl_Group.
void Fl_Table::insert | ( | Fl_Widget & | o, |
int | index | ||
) | [inline] |
The widget is removed from its current group (if any) and then inserted into this group.
It is put at index n - or at the end, if n >= children(). This can also be used to rearrange the widgets inside a group.
Reimplemented from Fl_Group.
This does insert(w, find(before)).
This will append the widget if before
is not in the group.
Reimplemented from Fl_Group.
int Fl_Table::is_interactive_resize | ( | ) | [inline] |
Returns 1 if someone is interactively resizing a row or column.
You can currently call this only from within your callback().
int Fl_Table::is_selected | ( | int | r, |
int | c | ||
) |
See if the cell at row r
and column c
is selected.
void Fl_Table::remove | ( | Fl_Widget & | o | ) | [inline] |
Removes a widget from the group but does not delete it.
This method does nothing if the widget is not a child of the group.
This method differs from the clear() method in that it only affects a single widget and does not delete it from memory.
Reimplemented from Fl_Group.
void Fl_Table::row_header | ( | int | flag | ) | [inline] |
Enables/disables showing the row headers.
1=enabled, 0=disabled. If changed, the table is redrawn.
void Fl_Table::row_height | ( | int | row, |
int | height | ||
) |
Sets the height of the specified row in pixels, and the table is redrawn.
callback() will be invoked with CONTEXT_RC_RESIZE if the row's height was actually changed, and when() is FL_WHEN_CHANGED.
void Fl_Table::row_height_all | ( | int | height | ) | [inline] |
Convenience method to set the height of all rows to the same value, in pixels.
The screen is redrawn.
void Fl_Table::row_resize | ( | int | flag | ) | [inline] |
Allows/disallows row resizing by the user.
1=allow interactive resizing, 0=disallow interactive resizing. Since interactive resizing is done via the row headers, row_header() must also be enabled to allow resizing.
void Fl_Table::row_resize_min | ( | int | val | ) | [inline] |
Sets the current row minimum resize value.
This is used to prevent the user from interactively resizing any row to be smaller than 'pixels'. Must be a value >=1.
void Fl_Table::set_selection | ( | int | row_top, |
int | col_left, | ||
int | row_bot, | ||
int | col_right | ||
) |
Sets the region of cells to be selected (highlighted).
So for instance, set_selection(0,0,0,0) selects the top/left cell in the table. And set_selection(0,0,1,1) selects the four cells in rows 0 and 1, column 0 and 1.
[in] | row_top | Top row of selection area |
[in] | col_left | Left column of selection area |
[in] | row_bot | Bottom row of selection area |
[in] | col_right | Right column of selection area |
void Fl_Table::table_box | ( | Fl_Boxtype | val | ) | [inline] |
Sets the kind of box drawn around the data table, the default being FL_NO_BOX.
Changing this value will cause the table to redraw.
void Fl_Table::top_row | ( | int | row | ) | [inline] |
Sets which row should be at the top of the table, scrolling as necessary, and the table is redrawn.
If the table cannot be scrolled that far, it is scrolled as far as possible.
int Fl_Table::top_row | ( | ) | [inline] |
Returns the current top row shown in the table.
This row may be partially obscured.
void Fl_Table::visible_cells | ( | int & | r1, |
int & | r2, | ||
int & | c1, | ||
int & | c2 | ||
) | [inline] |
Returns the range of row and column numbers for all visible and partially visible cells in the table.
These values can be used e.g. by your draw_cell() routine during CONTEXT_STARTPAGE to figure out what cells are about to be redrawn for the purposes of locking the data from a database before it's drawn.
leftcol rightcol
: :
toprow .. .-------------------.
| |
| V I S I B L E |
| |
| T A B L E |
| |
botrow .. '-------------------`
e.g. in a table where the visible rows are 5-20, and the visible columns are 100-120, then those variables would be:
void Fl_Table::when | ( | Fl_When | flags | ) |
The Fl_Widget::when() function is used to set a group of flags, determining when the widget callback is called:
FL_WHEN_CHANGED | callback() will be called when rows or columns are resized (interactively or via col_width() or row_height()), passing CONTEXT_RC_RESIZE via callback_context(). |
FL_WHEN_RELEASE | callback() will be called during FL_RELEASE events, such as when someone releases a mouse button somewhere on the table. |
The callback() routine is sent a TableContext that indicates the context the event occurred in, such as in a cell, in a header, or elsewhere on the table. When an event occurs in a cell or header, callback_row() and callback_col() can be used to determine the row and column. The callback can also look at the regular fltk event values (ie. Fl::event() and Fl::button()) to determine what kind of event is occurring.