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2.11.4 ScrolledWindow Object

ScrolledWindow objects are ControlsWindow objects with the following extra methods:

scrollbars([wantx[, wanty]])

Create (or destroy) horizontal and vertical scrollbars. The arguments specify which you want (default: both). The scrollbars always have minimum 0 and maximum 32767.

getscrollbarvalues()

You must supply this method. It should return a tuple (x, y) giving the current position of the scrollbars (between 0 and 32767). You can return None for either to indicate the whole document is visible in that direction.

updatescrollbars()

Call this method when the document has changed. It will call getscrollbarvalues() and update the scrollbars.

scrollbar_callback(which, what, value)

Supplied by you and called after user interaction. which will be 'x' or 'y', what will be '-', '-', 'set', '++' or '+'. For 'set', value will contain the new scrollbar position.

scalebarvalues(absmin, absmax, curmin, curmax)

Auxiliary method to help you calculate values to return from getscrollbarvalues(). You pass document minimum and maximum value and topmost (leftmost) and bottommost (rightmost) visible values and it returns the correct number or None.

do_activate(onoff, event)

Takes care of dimming/highlighting scrollbars when a window becomes frontmost. If you override this method, call this one at the end of your method.

do_postresize(width, height, window)

Moves scrollbars to the correct position. Call this method initially if you override it.

do_controlhit(window, control, pcode, event)

Handles scrollbar interaction. If you override it call this method first, a nonzero return value indicates the hit was in the scrollbars and has been handled.