Add atk/accessibility example

Cargo.toml

@@ -9,6 +9,9 @@ chrono = "0.4"
 url = "1.4"
 futures-preview = { version = "0.2", optional = true }
 
+[dependencies.atk]
+git = "https://github.com/gtk-rs/atk"
+
 [dependencies.glib]
 git = "https://github.com/gtk-rs/glib"
 
@@ -51,6 +54,9 @@ gtk_3_22_30 = ["gtk_3_22", "gtk/v3_22_30"] #for CI tools
 gio_2_40 = ["gio/v2_40"]
 futures-stable = ["futures-preview", "glib/futures", "gio/futures"]
 
+[[bin]]
+name = "accessibility"
+
 [[bin]]
 name = "basic"
 

src/bin/accessibility.rs

@@ -0,0 +1,63 @@
+//! # Accessibility example
+//!
+//! This sample demonstrates how to make an application more accessible.
+
+extern crate atk;
+extern crate gdk;
+extern crate gio;
+extern crate glib;
+extern crate gtk;
+
+use atk::prelude::*;
+use gio::prelude::*;
+use gtk::prelude::*;
+
+use std::env::args;
+
+fn build_ui(application: &gtk::Application) {
+    let window = gtk::ApplicationWindow::new(application);
+
+    window.set_title("Accessibility");
+    window.set_position(gtk::WindowPosition::Center);
+
+    let button = gtk::Button::new_with_label("Click me!");
+    let label = gtk::Label::new("0");
+    let vbox = gtk::Box::new(gtk::Orientation::Vertical, 0);
+
+    if let (Some(button_obj), Some(label_obj)) = (button.get_accessible(), label.get_accessible()) {
+        // We set the description
+        button_obj.set_description("Button to increase label value");
+
+        // Then we setup the relation saying that the label is linked to the button.
+        let relation_set = label_obj.ref_relation_set().expect("Failed to get relation for label");
+        let relation = atk::Relation::new(&[button_obj], atk::RelationType::LabelFor);
+
+        relation_set.add(&relation);
+    }
+
+    vbox.add(&button);
+    vbox.add(&label);
+
+    window.add(&vbox);
+
+    button.connect_clicked(move |_| {
+        let value = label.get_text().unwrap_or_else(|| "0".to_owned());
+        let value = u32::from_str_radix(&value, 10).unwrap_or_else(|_| 0) + 1;
+        label.set_text(&value.to_string());
+    });
+
+    window.show_all();
+}
+
+fn main() {
+    let application = gtk::Application::new("com.github.accessibility",
+                                            gio::ApplicationFlags::empty())
+                                       .expect("Initialization failed...");
+
+    application.connect_activate(|app| {
+        // We build the application UI.
+        build_ui(app);
+    });
+
+    application.run(&args().collect::<Vec<_>>());
+}