FLTK 1.3.0
Fl_Browser_ Class Reference

This is the base class for browsers. More...

#include <Fl_Browser_.H>

Inheritance diagram for Fl_Browser_:
Fl_Group Fl_Widget Fl_Browser Fl_Check_Browser Fl_File_Browser Fl_Hold_Browser Fl_Multi_Browser Fl_Select_Browser

List of all members.

Public Types

enum  {
  HORIZONTAL = 1, VERTICAL = 2, BOTH = 3, ALWAYS_ON = 4,
  HORIZONTAL_ALWAYS = 5, VERTICAL_ALWAYS = 6, BOTH_ALWAYS = 7
}
 Values for has_scrollbar(). More...

Public Member Functions

int deselect (int docallbacks=0)
 Deselects all items in the list and returns 1 if the state changed or 0 if it did not.
void display (void *item)
 Displays the item, scrolling the list as necessary.
int handle (int event)
 Handles the event within the normal widget bounding box.
uchar has_scrollbar () const
 Returns the current scrollbar mode, see Fl_Browser_::has_scrollbar(uchar)
void has_scrollbar (uchar mode)
 Sets whether the widget should have scrollbars or not (default Fl_Browser_::BOTH).
int hposition () const
 Gets the horizontal scroll position of the list as a pixel position pos.
void hposition (int)
 Sets the horizontal scroll position of the list to pixel position pos.
int position () const
 Gets the vertical scroll position of the list as a pixel position pos.
void position (int pos)
 Sets the vertical scroll position of the list to pixel position pos.
void resize (int X, int Y, int W, int H)
 Repositions and/or resizes the browser.
void scrollbar_left ()
 Moves the vertical scrollbar to the lefthand side of the list.
void scrollbar_right ()
 Moves the vertical scrollbar to the righthand side of the list.
int scrollbar_size () const
 Gets the current size of the scrollbars' troughs, in pixels.
void scrollbar_size (int size)
 Sets the pixel size of the scrollbars' troughs to the size, in pixels.
int scrollbar_width () const
 This method has been deprecated, existing for backwards compatibility only.
void scrollbar_width (int width)
 This method has been deprecated, existing for backwards compatibility only.
int select (void *item, int val=1, int docallbacks=0)
 Sets the selection state of item to val, and returns 1 if the state changed or 0 if it did not.
int select_only (void *item, int docallbacks=0)
 Selects item and returns 1 if the state changed or 0 if it did not.
void sort (int flags=0)
 Sort the items in the browser based on flags.
Fl_Color textcolor () const
 Gets the default text color for the lines in the browser.
void textcolor (Fl_Color col)
 Sets the default text color for the lines in the browser to color col.
Fl_Font textfont () const
 Gets the default text font for the lines in the browser.
void textfont (Fl_Font font)
 Sets the default text font for the lines in the browser to font.
Fl_Fontsize textsize () const
 Gets the default text size (in pixels) for the lines in the browser.
void textsize (Fl_Fontsize size)
 Sets the default text size (in pixels) for the lines in the browser to size.

Public Attributes

Fl_Scrollbar hscrollbar
 Horizontal scrollbar.
Fl_Scrollbar scrollbar
 Vertical scrollbar.

Protected Member Functions

void bbox (int &X, int &Y, int &W, int &H) const
 Returns the bounding box for the interior of the list's display window, inside the scrollbars.
void deleting (void *item)
 This method should be used when item is being deleted from the list.
int displayed (void *item) const
 Returns non-zero if item has been scrolled to a position where it is being displayed.
void draw ()
 Draws the list within the normal widget bounding box.
void * find_item (int ypos)
 This method returns the item under mouse y position ypos.
 Fl_Browser_ (int X, int Y, int W, int H, const char *L=0)
 The constructor makes an empty browser.
virtual int full_height () const
 This method may be provided by the subclass to indicate the full height of the item list, in pixels.
virtual int full_width () const
 This method may be provided by the subclass to indicate the full width of the item list, in pixels.
virtual int incr_height () const
 This method may be provided to return the average height of all items to be used for scrolling.
void inserting (void *a, void *b)
 This method should be used when an item is in the process of being inserted into the list.
virtual void * item_at (int index) const
 This method must be provided by the subclass to return the item for the specified index.
virtual void item_draw (void *item, int X, int Y, int W, int H) const =0
 This method must be provided by the subclass to draw the item in the area indicated by X, Y, W, H.
virtual void * item_first () const =0
 This method must be provided by the subclass to return the first item in the list.
virtual int item_height (void *item) const =0
 This method must be provided by the subclass to return the height of item in pixels.
virtual void * item_last () const
 This method must be provided by the subclass to return the last item in the list.
virtual void * item_next (void *item) const =0
 This method must be provided by the subclass to return the item in the list after item.
virtual void * item_prev (void *item) const =0
 This method must be provided by the subclass to return the item in the list before item.
virtual int item_quick_height (void *item) const
 This method may be provided by the subclass to return the height of the item, in pixels.
virtual void item_select (void *item, int val=1)
 This method must be implemented by the subclass if it supports multiple selections; sets the selection state to val for the item.
virtual int item_selected (void *item) const
 This method must be implemented by the subclass if it supports multiple selections; returns the selection state for item.
virtual void item_swap (void *a, void *b)
 This optional method should be provided by the subclass to efficiently swap browser items a and b, such as for sorting.
virtual const char * item_text (void *item) const
 This optional method returns a string (label) that may be used for sorting.
virtual int item_width (void *item) const =0
 This method must be provided by the subclass to return the width of the item in pixels.
int leftedge () const
 This method returns the X position of the left edge of the list area after adjusting for the scrollbar and border, if any.
void new_list ()
 This method should be called when the list data is completely replaced or cleared.
void redraw_line (void *item)
 This method should be called when the contents of item has changed, but not its height.
void redraw_lines ()
 This method will cause the entire list to be redrawn.
void replacing (void *a, void *b)
 This method should be used when item a is being replaced by item b.
void * selection () const
 Returns the item currently selected, or NULL if there is no selection.
void swapping (void *a, void *b)
 This method should be used when two items a and b are being swapped.
void * top () const
 Returns the item that appears at the top of the list.

Detailed Description

This is the base class for browsers.

To be useful it must be subclassed and several virtual functions defined. The Forms-compatible browser and the file chooser's browser are subclassed off of this.

This has been designed so that the subclass has complete control over the storage of the data, although because next() and prev() functions are used to index, it works best as a linked list or as a large block of characters in which the line breaks must be searched for.

A great deal of work has been done so that the "height" of a data object does not need to be determined until it is drawn. This is useful if actually figuring out the size of an object requires accessing image data or doing stat() on a file or doing some other slow operation.


Member Enumeration Documentation

anonymous enum

Values for has_scrollbar().

Anonymous enum bit flags for has_scrollbar().

  • bit 0: horizontal
  • bit 1: vertical
  • bit 2: 'always' (to be combined with bits 0 and 1)
  • bit 3-31: reserved for future use
Enumerator:
HORIZONTAL 

Only show horizontal scrollbar.

VERTICAL 

Only show vertical scrollbar.

BOTH 

Show both scrollbars. (default)

ALWAYS_ON 

Specified scrollbar(s) should 'always' be shown (to be used with HORIZONTAL/VERTICAL)

HORIZONTAL_ALWAYS 

Horizontal scrollbar always on.

VERTICAL_ALWAYS 

Vertical scrollbar always on.

BOTH_ALWAYS 

Both scrollbars always on.


Constructor & Destructor Documentation

Fl_Browser_::Fl_Browser_ ( int  X,
int  Y,
int  W,
int  H,
const char *  L = 0 
) [protected]

The constructor makes an empty browser.

Parameters:
[in]X,Y,W,Hposition and size.
[in]LThe label string, may be NULL.

Member Function Documentation

void Fl_Browser_::bbox ( int &  X,
int &  Y,
int &  W,
int &  H 
) const [protected]

Returns the bounding box for the interior of the list's display window, inside the scrollbars.

Parameters:
[out]X,Y,W,HThe returned bounding box.
(The original contents of these parameters are overwritten)
void Fl_Browser_::deleting ( void *  item) [protected]

This method should be used when item is being deleted from the list.

It allows the Fl_Browser_ to discard any cached data it has on the item. This method does not actually delete the item, but handles the follow up bookkeeping after the item has just been deleted.

Parameters:
[in]itemThe item being deleted.
int Fl_Browser_::deselect ( int  docallbacks = 0)

Deselects all items in the list and returns 1 if the state changed or 0 if it did not.

If the optional docallbacks parameter is non-zero, deselect tries to call the callback function for the widget.

Parameters:
[in]docallbacksIf 1, invokes widget callback if item changed.
If 0, doesn't do callback (default).
void Fl_Browser_::display ( void *  item)

Displays the item, scrolling the list as necessary.

Parameters:
[in]itemThe item to be displayed.
See also:
display(), displayed()
int Fl_Browser_::displayed ( void *  item) const [protected]

Returns non-zero if item has been scrolled to a position where it is being displayed.

Checks to see if the item's vertical position is within the top and bottom edges of the display window. This does NOT take into account the hide()/show() status of the widget or item.

Parameters:
[in]itemThe item to check
Returns:
1 if visible, 0 if not visible.
See also:
display(), displayed()
void * Fl_Browser_::find_item ( int  ypos) [protected]

This method returns the item under mouse y position ypos.

NULL is returned if no item is displayed at that position.

Parameters:
[in]yposThe y position (eg. Fl::event_y()) to find an item under.
Returns:
The item, or NULL if not found
int Fl_Browser_::full_height ( ) const [protected, virtual]

This method may be provided by the subclass to indicate the full height of the item list, in pixels.

The default implementation computes the full height from the item heights. Includes the items that are scrolled off screen.

Returns:
The height of the entire list, in pixels.

Reimplemented in Fl_Browser.

int Fl_Browser_::full_width ( ) const [protected, virtual]

This method may be provided by the subclass to indicate the full width of the item list, in pixels.

The default implementation computes the full width from the item widths.

Returns:
The maximum width of all the items, in pixels.
int Fl_Browser_::handle ( int  event) [virtual]

Handles the event within the normal widget bounding box.

Parameters:
[in]eventThe event to process.
Returns:
1 if event was processed, 0 if not.

Reimplemented from Fl_Group.

Reimplemented in Fl_Check_Browser.

void Fl_Browser_::has_scrollbar ( uchar  mode) [inline]

Sets whether the widget should have scrollbars or not (default Fl_Browser_::BOTH).

By default you can scroll in both directions, and the scrollbars disappear if the data will fit in the widget. has_scrollbar() changes this based on the value of mode:

  • 0 - No scrollbars.
int Fl_Browser_::hposition ( ) const [inline]

Gets the horizontal scroll position of the list as a pixel position pos.

The position returned is how many pixels of the list are scrolled off the left edge of the screen. Example: A position of '18' indicates the left 18 pixels of the list are scrolled off the left edge of the screen.

See also:
position(), hposition()
void Fl_Browser_::hposition ( int  pos)

Sets the horizontal scroll position of the list to pixel position pos.

The position is how many pixels of the list are scrolled off the left edge of the screen. Example: A position of '18' scrolls the left 18 pixels of the list off the left edge of the screen.

Parameters:
[in]posThe horizontal position (in pixels) to scroll the browser to.
See also:
position(), hposition()
int Fl_Browser_::incr_height ( ) const [protected, virtual]

This method may be provided to return the average height of all items to be used for scrolling.

The default implementation uses the height of the first item.

Returns:
The average height of items, in pixels.

Reimplemented in Fl_Browser.

void Fl_Browser_::inserting ( void *  a,
void *  b 
) [protected]

This method should be used when an item is in the process of being inserted into the list.

It allows the Fl_Browser_ to update its cache data as needed, scheduling a redraw for the affected lines. This method does not actually insert items, but handles the follow up bookkeeping after items have been inserted.

Parameters:
[in]aThe starting item position
[in]bThe new item being inserted
virtual void* Fl_Browser_::item_at ( int  index) const [inline, protected, virtual]

This method must be provided by the subclass to return the item for the specified index.

Parameters:
[in]indexThe index of the item to be returned
Returns:
The item at the specified index.

Reimplemented in Fl_Browser.

virtual void* Fl_Browser_::item_first ( ) const [protected, pure virtual]

This method must be provided by the subclass to return the first item in the list.

See also:
item_first(), item_next(), item_last(), item_prev()

Implemented in Fl_Browser.

virtual int Fl_Browser_::item_height ( void *  item) const [protected, pure virtual]

This method must be provided by the subclass to return the height of item in pixels.

Allow for two additional pixels for the list selection box.

Parameters:
[in]itemThe item whose height is returned.
Returns:
The height of the specified item in pixels.
See also:
item_height(), item_width(), item_quick_height()

Implemented in Fl_Browser.

virtual void* Fl_Browser_::item_last ( ) const [inline, protected, virtual]

This method must be provided by the subclass to return the last item in the list.

See also:
item_first(), item_next(), item_last(), item_prev()

Reimplemented in Fl_Browser.

virtual void* Fl_Browser_::item_next ( void *  item) const [protected, pure virtual]

This method must be provided by the subclass to return the item in the list after item.

See also:
item_first(), item_next(), item_last(), item_prev()

Implemented in Fl_Browser.

virtual void* Fl_Browser_::item_prev ( void *  item) const [protected, pure virtual]

This method must be provided by the subclass to return the item in the list before item.

See also:
item_first(), item_next(), item_last(), item_prev()

Implemented in Fl_Browser.

int Fl_Browser_::item_quick_height ( void *  item) const [protected, virtual]

This method may be provided by the subclass to return the height of the item, in pixels.

Allow for two additional pixels for the list selection box. This method differs from item_height in that it is only called for selection and scrolling operations. The default implementation calls item_height.

Parameters:
[in]itemThe item whose height to return.
Returns:
The height, in pixels.
void Fl_Browser_::item_select ( void *  item,
int  val = 1 
) [protected, virtual]

This method must be implemented by the subclass if it supports multiple selections; sets the selection state to val for the item.

Sets the selection state for item, where optional val is 1 (select, the default) or 0 (de-select).

Parameters:
[in]itemThe item to be selected
[in]valThe optional selection state; 1=select, 0=de-select.
The default is to select the item (1).

Reimplemented in Fl_Browser.

int Fl_Browser_::item_selected ( void *  item) const [protected, virtual]

This method must be implemented by the subclass if it supports multiple selections; returns the selection state for item.

The method should return 1 if item is selected, or 0 otherwise.

Parameters:
[in]itemThe item to test.

Reimplemented in Fl_Browser.

virtual void Fl_Browser_::item_swap ( void *  a,
void *  b 
) [inline, protected, virtual]

This optional method should be provided by the subclass to efficiently swap browser items a and b, such as for sorting.

Parameters:
[in]a,bThe two items to be swapped.

Reimplemented in Fl_Browser.

virtual const char* Fl_Browser_::item_text ( void *  item) const [inline, protected, virtual]

This optional method returns a string (label) that may be used for sorting.

Parameters:
[in]itemThe item whose label text is returned.
Returns:
The item's text label. (Can be NULL if blank)

Reimplemented in Fl_Browser.

virtual int Fl_Browser_::item_width ( void *  item) const [protected, pure virtual]

This method must be provided by the subclass to return the width of the item in pixels.

Allow for two additional pixels for the list selection box.

Parameters:
[in]itemThe item whose width is returned.
Returns:
The width of the item in pixels.

Implemented in Fl_Browser.

int Fl_Browser_::leftedge ( ) const [protected]

This method returns the X position of the left edge of the list area after adjusting for the scrollbar and border, if any.

Returns:
The X position of the left edge of the list, in pixels.
See also:
Fl_Browser_::bbox()
void Fl_Browser_::new_list ( ) [protected]

This method should be called when the list data is completely replaced or cleared.

It informs the Fl_Browser_ widget that any cached information it has concerning the items is invalid. This method does not clear the list, it just handles the follow up bookkeeping after the list has been cleared.

int Fl_Browser_::position ( ) const [inline]

Gets the vertical scroll position of the list as a pixel position pos.

The position returned is how many pixels of the list are scrolled off the top edge of the screen. Example: A position of '3' indicates the top 3 pixels of the list are scrolled off the top edge of the screen.

See also:
position(), hposition()
void Fl_Browser_::position ( int  pos)

Sets the vertical scroll position of the list to pixel position pos.

The position is how many pixels of the list are scrolled off the top edge of the screen. Example: A position of '3' scrolls the top three pixels of the list off the top edge of the screen.

Parameters:
[in]posThe vertical position (in pixels) to scroll the browser to.
See also:
position(), hposition()
void Fl_Browser_::redraw_line ( void *  item) [protected]

This method should be called when the contents of item has changed, but not its height.

Parameters:
[in]itemThe item that needs to be redrawn.
See also:
redraw_lines(), redraw_line()
void Fl_Browser_::redraw_lines ( ) [inline, protected]

This method will cause the entire list to be redrawn.

See also:
redraw_lines(), redraw_line()
void Fl_Browser_::replacing ( void *  a,
void *  b 
) [protected]

This method should be used when item a is being replaced by item b.

It allows the Fl_Browser_ to update its cache data as needed, schedules a redraw for the item being changed, and tries to maintain the selection. This method does not actually replace the item, but handles the follow up bookkeeping after the item has just been replaced.

Parameters:
[in]aItem being replaced
[in]bItem to replace 'a'
void Fl_Browser_::resize ( int  X,
int  Y,
int  W,
int  H 
) [virtual]

Repositions and/or resizes the browser.

Parameters:
[in]X,Y,W,HThe new position and size for the browser, in pixels.

Reimplemented from Fl_Group.

void Fl_Browser_::scrollbar_left ( ) [inline]

Moves the vertical scrollbar to the lefthand side of the list.

For back compatibility.

void Fl_Browser_::scrollbar_right ( ) [inline]

Moves the vertical scrollbar to the righthand side of the list.

For back compatibility.

int Fl_Browser_::scrollbar_size ( ) const [inline]

Gets the current size of the scrollbars' troughs, in pixels.

If this value is zero (default), this widget will use the Fl::scrollbar_size() value as the scrollbar's width.

Returns:
Scrollbar size in pixels, or 0 if the global Fl::scrollsize() is being used.
See also:
Fl::scrollbar_size(int)
void Fl_Browser_::scrollbar_size ( int  size) [inline]

Sets the pixel size of the scrollbars' troughs to the size, in pixels.

Normally you should not need this method, and should use Fl::scrollbar_size(int) instead to manage the size of ALL your widgets' scrollbars. This ensures your application has a consistent UI, is the default behavior, and is normally what you want.

Only use THIS method if you really need to override the global scrollbar size. The need for this should be rare.

Setting size to the special value of 0 causes the widget to track the global Fl::scrollbar_size(), which is the default.

Parameters:
[in]sizeSets the scrollbar size in pixels.
If 0 (default), scrollbar size tracks the global Fl::scrollbar_size()
See also:
Fl::scrollbar_size()
int Fl_Browser_::scrollbar_width ( ) const [inline]

This method has been deprecated, existing for backwards compatibility only.

Use scrollbar_size() instead. This method always returns the global value Fl::scrollbar_size().

Returns:
Always returns the global value Fl::scrollbar_size().
Todo:
This method should eventually be removed in 1.4+
void Fl_Browser_::scrollbar_width ( int  width) [inline]

This method has been deprecated, existing for backwards compatibility only.

Use scrollbar_size(int) instead. This method sets the global Fl::scrollbar_size(), and forces this instance of the widget to use it.

Todo:
This method should eventually be removed in 1.4+
int Fl_Browser_::select ( void *  item,
int  val = 1,
int  docallbacks = 0 
)

Sets the selection state of item to val, and returns 1 if the state changed or 0 if it did not.

If docallbacks is non-zero, select tries to call the callback function for the widget.

Parameters:
[in]itemThe item whose selection state is to be changed
[in]valThe new selection state (1=select, 0=de-select)
[in]docallbacksIf 1, invokes widget callback if item changed.
If 0, doesn't do callback (default).
Returns:
1 if state was changed, 0 if not.
int Fl_Browser_::select_only ( void *  item,
int  docallbacks = 0 
)

Selects item and returns 1 if the state changed or 0 if it did not.

Any other items in the list are deselected.

Parameters:
[in]itemThe item to select.
[in]docallbacksIf 1, invokes widget callback if item changed.
If 0, doesn't do callback (default).
void* Fl_Browser_::selection ( ) const [inline, protected]

Returns the item currently selected, or NULL if there is no selection.

For multiple selection browsers this call returns the currently focused item, even if it is not selected. To find all selected items, call Fl_Multi_Browser::selected() for every item in question.

void Fl_Browser_::sort ( int  flags = 0)

Sort the items in the browser based on flags.

item_swap(void*, void*) and item_text(void*) must be implemented for this call.

Parameters:
[in]flagsFL_SORT_ASCENDING -- sort in ascending order
FL_SORT_DESCENDING -- sort in descending order
Values other than the above will cause undefined behavior
Other flags may appear in the future.
Todo:
Add a flag to ignore case
void Fl_Browser_::swapping ( void *  a,
void *  b 
) [protected]

This method should be used when two items a and b are being swapped.

It allows the Fl_Browser_ to update its cache data as needed, schedules a redraw for the two items, and tries to maintain the current selection. This method does not actually swap items, but handles the follow up bookkeeping after items have been swapped.

Parameters:
[in]a,bItems being swapped.
Fl_Font Fl_Browser_::textfont ( ) const [inline]

Gets the default text font for the lines in the browser.

See also:
textfont(), textsize(), textcolor()

Member Data Documentation

Horizontal scrollbar.

Public, so that it can be accessed directly.

Vertical scrollbar.

Public, so that it can be accessed directly.


The documentation for this class was generated from the following files: