[oe] [meta-xfce][PATCH 1/1] xfwm4: add patch to fix touch event handling

[Ioan-Adrian Ratiu]

On Thu, 28 Jan 2016 12:52:06 +0100
Andreas Müller <schnitzeltony at googlemail.com> wrote:

> On Thu, Jan 28, 2016 at 11:54 AM, Ioan-Adrian Ratiu <adrian.ratiu at ni.com> wrote:
> > Patch sent upstream, pending acceptance
> >
> > Signed-off-by: Ioan-Adrian Ratiu <adrian.ratiu at ni.com>
> > ---
> >  ...handling-of-touch-events-on-window-border.patch | 42 ++++++++++++++++++++++
> >  meta-xfce/recipes-xfce/xfwm4/xfwm4_4.12.3.bb       |  6 +++-
> >  2 files changed, 47 insertions(+), 1 deletion(-)
> >  create mode 100644 meta-xfce/recipes-xfce/xfwm4/files/0001-events-fix-handling-of-touch-events-on-window-border.patch
> >
> > diff --git a/meta-xfce/recipes-xfce/xfwm4/files/0001-events-fix-handling-of-touch-events-on-window-border.patch b/meta-xfce/recipes-xfce/xfwm4/files/0001-events-fix-handling-of-touch-events-on-window-border.patch
> > new file mode 100644
> > index 0000000..e01aac5
> > --- /dev/null
> > +++ b/meta-xfce/recipes-xfce/xfwm4/files/0001-events-fix-handling-of-touch-events-on-window-border.patch
> > @@ -0,0 +1,42 @@
> > +From cb966e51ea51088a1d4fd5914fc7f917684e0b51 Mon Sep 17 00:00:00 2001
> > +From: Ioan-Adrian Ratiu <adrian.ratiu at ni.com>
> > +Date: Thu, 28 Jan 2016 11:43:01 +0200
> > +Subject: [PATCH] events: fix handling of touch events on window borders
> > +
> > +When the Xorg server translates touch events into ButtonPress/ButtonRelease
> > +events, the subwindow in the XEvent structure is set to zero. This change adds
> > +a querry to determine the subwindow for the event in case it is missing.
> > +
> > +Original patch & discussion at [1].
> > +
> > +Upstream-Status: Pending acceptance
> > +
> > +[1] http://xfce.10915.n7.nabble.com/Re-Xfwm-window-borders-do-not-respond-to-touch-screen-td42357.html
> > +
> > +Signed-off-by: Gratian Crisan <gratian.crisan at ni.com>
> > +Signed-off-by: Ioan-Adrian Ratiu <adrian.ratiu at ni.com>
> > +---
> > + src/events.c | 7 +++++++
> > + 1 file changed, 7 insertions(+)
> > +
> > +diff --git a/src/events.c b/src/events.c
> > +index 8aa0f0a..0565594 100644
> > +--- a/src/events.c
> > ++++ b/src/events.c
> > +@@ -917,6 +917,13 @@ handleButtonPress (DisplayInfo *display_info, XButtonEvent * ev)
> > +     {
> > +         state = ev->state & MODIFIER_MASK;
> > +         win = ev->subwindow;
> > ++        if (!win) {
> > ++                Window root_ret;
> > ++                int rx,ry,wx,wy;
> > ++                unsigned int mask_ret;
> > ++                XQueryPointer(display_info->dpy, ev->window,
> > ++                              &root_ret, &win, &rx, &ry, &wx, &wy, &mask_ret);
> > ++        }
> > +         screen_info = c->screen_info;
> > +
> > +         if ((ev->button == Button1) && (state) && (state == screen_info->params->easy_click))
> > +--
> > +2.7.0
> > +
> > diff --git a/meta-xfce/recipes-xfce/xfwm4/xfwm4_4.12.3.bb b/meta-xfce/recipes-xfce/xfwm4/xfwm4_4.12.3.bb
> > index 41daa00..aa4b290 100644
> > --- a/meta-xfce/recipes-xfce/xfwm4/xfwm4_4.12.3.bb
> > +++ b/meta-xfce/recipes-xfce/xfwm4/xfwm4_4.12.3.bb
> > @@ -6,7 +6,11 @@ DEPENDS = "virtual/libx11 libxpm gtk+ libxfce4util libxfce4ui xfconf libwnck dbu
> >
> >  inherit xfce update-alternatives
> >
> > -SRC_URI += "file://0001-don-t-block-display-events-when-time-is-set-backward.patch"
> > +SRC_URI += " \
> > +    file://0001-don-t-block-display-events-when-time-is-set-backward.patch \
> > +    file://0001-events-fix-handling-of-touch-events-on-window-border.patch \
> > +"
> > +
> >  SRC_URI[md5sum] = "197ef087ca6a263627f1bea6d5a79d6f"
> >  SRC_URI[sha256sum] = "f4a988fbc4e0df7e8583c781d271559e56fd28696092f94ae052e9e6edb09eac"
> >
> > --
> > 2.7.0
> >  
> I've checked the thread you point to: I am using xfce for touch
> screens and can resize windows, maximize them, move around and close
> them all with touch. What kind of error is fixed?

Thank you for challenging this, it helped bring more light on the issue.
It is a workaround the bug [1] in xserver which was fixed. More details here [2]
I did not knew this untill I asked on the xfwm bugzilla.

So instead of "fixing" it here, we should try to backport that fix to OE or verify
if it's not contained in OE's xserver already since it's working for you :)

[1] http://cgit.freedesktop.org/xorg/xserver/commit/?id=24b943132f
[2] https://bugzilla.xfce.org/show_bug.cgi?id=12427

> 
> Andreas