While it's possible to scroll GtkScrolledWindow with touchscreen gestures,
currently it doesn't work for touchpad: GtkScrolledWindow never propagates
scroll events and if multiple scrolled windows are nested, only the inner
one will receive any events.
Since e9fe270e94
, GtkScrolledWindow handles
only full scroll sequences, but still accepts any scroll sequence, causing
issues with nested scrolling.
Take another step and keep track of the sequence state, checking the
direction when a smooth scroll starts and only claiming the sequence if
the scrolled window can scroll in the direction of the current scrolling,
and otherwise denying it and ignoring any further events until it ends.
The check must be done on the bubble phase because if there are nested
scrolled windows that can scroll in the same direction, we want to pick
the inner one and not the outer one. The check also has to be done in the
scroll signal handler, since we don't have scroll deltas available in
scroll-begin. After we determine the direction and claim the sequence, we
can switch to the capture phase and proceed with scrolling as usual.
This also means that there are 3 states of the sequence state: a sequence
can be claimed, denied, or during the first invocation of the scroll signal
handler it's undecided. This neatly maps to GtkEventSequenceState, so we
can reuse it.
GTK — The GTK toolkit
General information
GTK is a multi-platform toolkit for creating graphical user interfaces. Offering a complete set of widgets, GTK is suitable for projects ranging from small one-off projects to complete application suites.
GTK is free software and part of the GNU Project. However, the licensing terms for GTK, the GNU LGPL, allow it to be used by all developers, including those developing proprietary software, without any license fees or royalties.
The official download location
The official web site
The official developers blog
Discussion forum
Nightly documentation can be found at
- Gtk: https://gnome.pages.gitlab.gnome.org/gtk/gtk/
- Gdk: https://gnome.pages.gitlab.gnome.org/gtk/gdk/
- Gsk: https://gnome.pages.gitlab.gnome.org/gtk/gsk/
Building and installing
In order to build GTK you will need:
You will also need various dependencies, based on the platform you are building for:
If you are building the X11 backend, you will also need:
- Xlib, and the following X extensions:
- xrandr
- xrender
- xi
- xext
- xfixes
- xcursor
- xdamage
- xcomposite
If you are building the Wayland backend, you will also need:
- Wayland-client
- Wayland-protocols
- Wayland-cursor
- Wayland-EGL
Once you have all the necessary dependencies, you can build GTK by using Meson:
$ meson _build .
$ cd _build
$ ninja
You can run the test suite using:
$ meson test
And, finally, you can install GTK using:
$ sudo ninja install
Complete information about installing GTK and related libraries can be found in the file:
docs/reference/gtk/html/gtk-building.html
Or online
How to report bugs
Bugs should be reported on the issues page.
In the bug report please include:
-
Information about your system. For instance:
- which version of GTK you are using
- what operating system and version
- for Linux, which distribution
- if you built GTK, the list of options used to configure the build
And anything else you think is relevant.
-
How to reproduce the bug.
If you can reproduce it with one of the demo applications that are built in the demos/ subdirectory, on one of the test programs that are built in the tests/ subdirectory, that will be most convenient. Otherwise, please include a short test program that exhibits the behavior. As a last resort, you can also provide a pointer to a larger piece of software that can be downloaded.
-
If the bug was a crash, the exact text that was printed out when the crash occurred.
-
Further information such as stack traces may be useful, but is not necessary.
Contributing to GTK
Please, follow the contribution guide to know how to start contributing to GTK.
Release notes
The release notes for GTK are part of the migration guide in the API reference. See:
Licensing terms
GTK is released under the terms of the GNU Lesser General Public License, version 2.1 or, at your option, any later version, as published by the Free Software Foundation.
Please, see the COPYING
file for further information.
GTK includes a small number of source files under the Apache license:
- A fork of the roaring bitmaps implementation in gtk/roaring
- An adaptation of timsort from python in gtk/timsort