[gtk] Add appdata for gtk4-demo

[Matthias Clasen <matthiasc src gnome org>]

commit cb41d1586fd2dbb0c1bade74baa32d3b423673c0
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Mar 20 19:40:30 2018 -0400

    Add appdata for gtk4-demo
    
    This will let us build a better flatpak for gtk4-demo.

 demos/gtk-demo/meson.build              |  3 +++
 demos/gtk-demo/org.gtk.Demo.appdata.xml | 33 +++++++++++++++++++++++++++++++++
 meson.build                             |  1 +
 3 files changed, 37 insertions(+)
---
diff --git a/demos/gtk-demo/meson.build b/demos/gtk-demo/meson.build
index 6734d6f110..1317c29904 100644
--- a/demos/gtk-demo/meson.build
+++ b/demos/gtk-demo/meson.build
@@ -131,3 +131,6 @@ install_data('gtk4-demo.desktop', install_dir: gtk_applicationsdir)
 # GSettings
 install_data('org.gtk.Demo.gschema.xml', install_dir: gtk_schemasdir)
 gnome.compile_schemas()
+
+# appdata
+install_data('org.gtk.Demo.appdata.xml', install_dir: gtk_appdatadir)
\ No newline at end of file
diff --git a/demos/gtk-demo/org.gtk.Demo.appdata.xml b/demos/gtk-demo/org.gtk.Demo.appdata.xml
new file mode 100644
index 0000000000..65902b74c3
--- /dev/null
+++ b/demos/gtk-demo/org.gtk.Demo.appdata.xml
@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<component type="desktop">
+  <id>org.gtk.Demo.desktop</id>
+  <metadata_license>CC0-1.0</metadata_license>
+  <project_license>LGPL-2.0+</project_license>
+  <name>GTK+ Demo</name>
+  <summary>Program to demonstrate GTK+ functions</summary>
+  <description>
+    <p>
+      GTK+ Demo is a collection of examples that demonstrate the major
+      features of the GTK+ toolkit.
+    </p>
+  </description>
+  <screenshots>
+    <screenshot>
+      <image>https://static.gnome.org/appdata/gtk4-demo/gtk-demo1.png</image>
+      <caption>The main window</caption>
+    </screenshot>
+    <screenshot>
+      <image>https://static.gnome.org/appdata/gtk4-demo/gtk-demo2.png</image>
+      <caption>An example</caption>
+    </screenshot>
+  </screenshots>
+  <kudos>
+    <kudo>AppMenu</kudo>
+    <kudo>HiDpiIcon</kudo>
+    <kudo>ModernToolkit</kudo>
+  </kudos>
+  <url type="homepage">https://www.gtk.org</url>
+  <translation type="gettext">gtk-4.0</translation>
+  <update_contact>matthias.clasen_at_gmail.com</update_contact>
+  <developer_name>Matthias Clasen and others</developer_name>
+</component>
\ No newline at end of file
diff --git a/meson.build b/meson.build
index c2d0e51338..26d522fa3b 100644
--- a/meson.build
+++ b/meson.build
@@ -125,6 +125,7 @@ gtk_localedir = join_paths(gtk_prefix, get_option('localedir'))
 gtk_sysconfdir = join_paths(gtk_prefix, get_option('sysconfdir'))
 gtk_applicationsdir = join_paths(gtk_datadir, 'applications')
 gtk_schemasdir = join_paths(gtk_datadir, 'glib-2.0/schemas')
+gtk_appdatadir = join_paths(gtk_datadir, 'metainfo')
 
 cc = meson.get_compiler('c')