Another run at the problem 57516164de was meant to solve. The
new solution just gives up when a `drawRect:' method is called
in the wrong thread, which might create refresh glitches but
avoids a deadlock in the case that the Racket thread is blocked
on the update happening in the foreign thread.
Register a button as a default button every time that it is shown,
so that multiple buttons in a frame can have the 'border style
(as long as only one is shown at a time).
On Cocoa, a view's `drawRect:' method can be called from a
heartbeat thread that animates controls. Such a call happens
rarely for a `canvas%' or other class where `drawRect:'
is overridden, but since it can happen, ensure that the
callback runs on the Racket thread.
The relevant `on-paint' call is one that is forced for a GL
canvas to try to draw a frame's content before the frame is
shown. Sometimes, thread scheduling would let the frame get
sufficiently initialized at the Cocoa level before the `on-paint'
call happened, but sometimes not.
The code to draw a border has to determine the widget's position
within the drawing window. Gtk 3.0 has a function to provide that
transformation, but Gtk 2.0 doesn't seem to have one, and it seems
that the transformation implemented in `racket/gui' wasn't right.
Closes PR 13453
There appears to be no way to make `on-demand' work right for the
Unity window manager's global menu bar, since there's no notificiation
when the menu bar is clicked. We approximate the correct behavior
by calling `on-demand' when a containing frame loses the keyboard
focus, which might be because the menu bar was clicked; that may be
too late (because the menu has already been shown), but it should
work most of the time.
Closes PR 13347.
Relevant to PR 13395, but DrRacket will have to change to work
around the remaining limitations of `on-demand'.
I started from tabs that are not on the beginning of lines, and in
several places I did further cleanings.
If you're worried about knowing who wrote some code, for example, if you
get to this commit in "git blame", then note that you can use the "-w"
flag in many git commands to ignore whitespaces. For example, to see
per-line authors, use "git blame -w <file>". Another example: to see
the (*much* smaller) non-whitespace changes in this (or any other)
commit, use "git log -p -w -1 <sha1>".
Cairo doesn't seem to deal correctly with an HDC produced
by BeginPaint() that has a clipping region. The problem affects
only Win64. Work around the problem by drawing to a separate
HDC and copying to/from the screen. (To see the problem before
this patch, draw the DrRacket window to the edge of the screen
and back, and observe tha the toolbar doesn't update correctly.)
This change could affect performance, but it should mostly
be limited to refresh when a window moves.
When the theme-specified default font has a localized name,
using it as a Pango faily name doesn't work, with the result that
text on controls could be truncated. Get a Pango-friendly
name by converting a LOGFONT to a Pango font description and
getting the name from the font description.
