Add example: Combobox with list store

Author: ski0090

Diff for: examples/Cargo.toml

@@ -74,6 +74,10 @@ path = "clock/main.rs"
 name = "clone_macro"
 path = "clone_macro/main.rs"
 
+[[bin]]
+name = "combobox_liststore"
+path = "combobox_liststore/main.rs"
+
 [[bin]]
 name = "communication_thread"
 path = "communication_thread/main.rs"

Diff for: examples/combobox_liststore/README.md

@@ -0,0 +1,11 @@
+# Combobox liststore
+
+Example on how to use combobox and liststore.
+
+Run it by executing:
+
+```bash
+cargo run --bin combobox_liststore
+```
+
+![screenshot](screenshot.png)

Diff for: examples/combobox_liststore/main.rs

@@ -0,0 +1,100 @@
+use glib::clone;
+use gtk::{
+    prelude::*, CellRendererText, CellRendererToggle, ComboBox, Entry, ListStore, TreeModel,
+};
+use std::{cell::RefCell, rc::Rc};
+
+fn build_ui(application: &gtk::Application) {
+    let window = gtk::ApplicationWindow::new(application);
+    window.set_title("First GTK+ Program");
+    window.set_border_width(10);
+    window.set_position(gtk::WindowPosition::Center);
+    window.set_default_size(350, 70);
+
+    let combobox = gtk::ComboBox::new();
+    let renderer = CellRendererToggle::new();
+    combobox.pack_start(&renderer, true);
+    combobox.add_attribute(&renderer, "active", 0);
+
+    let renderer = CellRendererText::new();
+    combobox.pack_start(&renderer, true);
+    combobox.add_attribute(&renderer, "text", 1);
+    combobox.set_entry_text_column(1);
+
+    let model = gtk::ListStore::new(&[glib::Type::BOOL, glib::Type::STRING]);
+    let data: [(u32, &dyn ToValue); 2] = [(0, &true), (1, &"data1")];
+    model.insert_with_values(Some(0), &data);
+    let data: [(u32, &dyn ToValue); 2] = [(0, &false), (1, &"date2")];
+    model.insert_with_values(Some(1), &data);
+    let data: [(u32, &dyn ToValue); 2] = [(0, &false), (1, &"date3")];
+    model.insert_with_values(Some(2), &data);
+
+    combobox.set_model(Some(&model));
+    window.add(&combobox);
+    let entry = gtk::Entry::new();
+    entry.set_editable(false);
+    combobox.add(&entry);
+
+    combobox.connect_changed(clone!(
+        @weak entry => move |cb| {
+        let model = cb.property::<TreeModel>("model");
+        let store = model.dynamic_cast_ref::<ListStore>().unwrap();
+        if let Some(iter) = cb.active_iter() {
+            let value = store.value(&iter, 0).get::<bool>().unwrap();
+            store.set(&iter, &[(0, &!value)]);
+        }
+        update_entry(&entry, cb);
+        cb.set_active_iter(None);
+    }));
+    combobox.connect_map(move |cb| update_entry(&entry, cb));
+    window.show_all();
+}
+
+fn for_each<F: Fn(&gtk::ComboBox, &gtk::TreeIter, &ListStore)>(cb: &gtk::ComboBox, f: F) {
+    let model = cb.property::<TreeModel>("model");
+    if let Some(iter) = model.iter_first() {
+        let store = model.dynamic_cast_ref::<ListStore>().unwrap();
+
+        loop {
+            f(cb, &iter, store);
+            #[cfg(debug_assertions)]
+            {
+                if !store.iter_is_valid(&iter) {
+                    unreachable!("iter is not valid: Don't remove iter in for_each.")
+                }
+            }
+
+            if !model.iter_next(&iter) {
+                break;
+            }
+        }
+    }
+}
+
+fn update_entry(entry: &Entry, cb: &ComboBox) {
+    entry.set_text("");
+    let vec_string: Vec<String> = Default::default();
+    let vec_string = Rc::new(RefCell::new(vec_string));
+    for_each(
+        cb,
+        clone!(
+            @weak vec_string, => move |_, iter, store| {
+            if store.value(iter, 0).get::<bool>().unwrap() {
+                let value = store.value(iter, 1).get::<String>().unwrap();
+                vec_string.borrow_mut().push(value);
+            }
+        }),
+    );
+    entry.set_text(vec_string.borrow().join(", ").as_str());
+}
+
+fn main() {
+    let application = gtk::Application::new(
+        Some("com.github.gtk-rs.examples.combobox_liststore"),
+        Default::default(),
+    );
+
+    application.connect_activate(build_ui);
+
+    application.run();
+}