From 8c6c8df8f4bd07602931485956fce524925dc2bb Mon Sep 17 00:00:00 2001 From: Simon Tatham Date: Sat, 2 Apr 2011 15:36:30 +0000 Subject: Add functions provided by the midend to tell a front end whether GUI buttons for undo and redo should currently be greyed out. [originally from svn r9139] --- devel.but | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'devel.but') diff --git a/devel.but b/devel.but index 8e35359..076ef8b 100644 --- a/devel.but +++ b/devel.but @@ -3096,6 +3096,24 @@ The front end can expect its drawing API and/or \cw{activate_timer()} to be called from within a call to this function. +\H{midend-can-undo} \cw{midend_can_undo()} + +\c int midend_can_undo(midend *me); + +Returns \cw{TRUE} if the midend is currently in a state where the undo +operation is meaningful (i.e. at least one position exists on the undo +chain before the present one). Front ends may wish to use this to +visually activate and deactivate an undo button. + +\H{midend-can-redo} \cw{midend_can_redo()} + +\c int midend_can_redo(midend *me); + +Returns \cw{TRUE} if the midend is currently in a state where the redo +operation is meaningful (i.e. at least one position exists on the redo +chain after the present one). Front ends may wish to use this to +visually activate and deactivate a redo button. + \H{midend-serialise} \cw{midend_serialise()} \c void midend_serialise(midend *me, -- cgit v1.1