book: Extend memory management chapter

book/listings/Cargo.toml

@@ -102,6 +102,10 @@ path = "g_object_memory_management/3/main.rs"
 name = "g_object_memory_management_4"
 path = "g_object_memory_management/4/main.rs"
 
+[[bin]]
+name = "g_object_memory_management_5"
+path = "g_object_memory_management/5/main.rs"
+
 # g_object_properties
 [[bin]]
 name = "g_object_properties_1"

book/listings/g_object_memory_management/1/main.rs

@@ -1,8 +1,6 @@
-use std::cell::Cell;
-use std::rc::Rc;
-
 use gtk::prelude::*;
-use gtk::{self, glib, Application, ApplicationWindow, Button, Orientation};
+use gtk::{glib, Application, ApplicationWindow, Button};
+use std::cell::Cell;
 
 const APP_ID: &str = "org.gtk_rs.GObjectMemoryManagement1";
 
@@ -16,7 +14,9 @@ fn main() -> glib::ExitCode {
  // Run the application
  app.run()
 }
-fn build_ui(app: &Application) {
+
+// ANCHOR: build_ui
+fn build_ui(application: &Application) {
  // Create two buttons
  let button_increase = Button::builder()
  .label("Increase")
@@ -25,38 +25,22 @@ fn build_ui(app: &Application) {
  .margin_start(12)
  .margin_end(12)
  .build();
- let button_decrease = Button::builder()
- .label("Decrease")
- .margin_top(12)
- .margin_bottom(12)
- .margin_start(12)
- .margin_end(12)
- .build();
 
- // ANCHOR: callback
- // Reference-counted object with inner-mutability
- let number = Rc::new(Cell::new(0));
+ // A mutable integer
+ let number = Cell::new(0);
 
- // Connect callbacks, when a button is clicked `number` will be changed
- let number_copy = number.clone();
- button_increase.connect_clicked(move |_| number_copy.set(number_copy.get() + 1));
- button_decrease.connect_clicked(move |_| number.set(number.get() - 1));
- // ANCHOR_END: callback
-
- // Add buttons to `gtk_box`
- let gtk_box = gtk::Box::builder()
- .orientation(Orientation::Vertical)
- .build();
- gtk_box.append(&button_increase);
- gtk_box.append(&button_decrease);
+ // Connect callbacks
+ // When a button is clicked, `number` should be changed
+ button_increase.connect_clicked(move |_| number.set(number.get() + 1));
 
  // Create a window
  let window = ApplicationWindow::builder()
- .application(app)
+ .application(application)
  .title("My GTK App")
- .child(&gtk_box)
+ .child(&button_increase)
  .build();
 
  // Present the window
  window.present();
 }
+// ANCHOR_END: build_ui

book/listings/g_object_memory_management/2/main.rs

@@ -1,7 +1,6 @@
 use std::cell::Cell;
 use std::rc::Rc;
 
-use glib::clone;
 use gtk::prelude::*;
 use gtk::{self, glib, Application, ApplicationWindow, Button, Orientation};
 
@@ -34,17 +33,14 @@ fn build_ui(app: &Application) {
  .margin_end(12)
  .build();
 
- // Reference-counted object with inner mutability
- let number = Rc::new(Cell::new(0));
- // Connect callbacks
- // When a button is clicked, `number` will be changed
  // ANCHOR: callback
- button_increase.connect_clicked(clone!(@strong number => move |_| {
- number.set(number.get() + 1);
- }));
- button_decrease.connect_clicked(move |_| {
- number.set(number.get() - 1);
- });
+ // Reference-counted object with inner-mutability
+ let number = Rc::new(Cell::new(0));
+
+ // Connect callbacks, when a button is clicked `number` will be changed
+ let number_copy = number.clone();
+ button_increase.connect_clicked(move |_| number_copy.set(number_copy.get() + 1));
+ button_decrease.connect_clicked(move |_| number.set(number.get() - 1));
  // ANCHOR_END: callback
 
  // Add buttons to `gtk_box`

book/listings/g_object_memory_management/3/main.rs

@@ -17,7 +17,6 @@ fn main() -> glib::ExitCode {
  // Run the application
  app.run()
 }
-
 fn build_ui(app: &Application) {
  // Create two buttons
  let button_increase = Button::builder()
@@ -35,21 +34,17 @@ fn build_ui(app: &Application) {
  .margin_end(12)
  .build();
 
+ // Reference-counted object with inner mutability
  let number = Rc::new(Cell::new(0));
-
- // ANCHOR: callback
  // Connect callbacks
- // When a button is clicked, `number` and label of the other button will be changed
- button_increase.connect_clicked(clone!(@weak number, @strong button_decrease =>
- move |_| {
- number.set(number.get() + 1);
- button_decrease.set_label(&number.get().to_string());
- }));
- button_decrease.connect_clicked(clone!(@strong button_increase =>
- move |_| {
- number.set(number.get() - 1);
- button_increase.set_label(&number.get().to_string());
+ // When a button is clicked, `number` will be changed
+ // ANCHOR: callback
+ button_increase.connect_clicked(clone!(@strong number => move |_| {
+ number.set(number.get() + 1);
  }));
+ button_decrease.connect_clicked(move |_| {
+ number.set(number.get() - 1);
+ });
  // ANCHOR_END: callback
 
  // Add buttons to `gtk_box`

book/listings/g_object_memory_management/4/main.rs

@@ -35,41 +35,36 @@ fn build_ui(app: &Application) {
  .margin_end(12)
  .build();
 
- // Reference-counted object with inner mutability
  let number = Rc::new(Cell::new(0));
 
  // ANCHOR: callback
  // Connect callbacks
  // When a button is clicked, `number` and label of the other button will be changed
- button_increase.connect_clicked(clone!(@weak number, @weak button_decrease =>
+ button_increase.connect_clicked(clone!(@weak number, @strong button_decrease =>
  move |_| {
  number.set(number.get() + 1);
  button_decrease.set_label(&number.get().to_string());
  }));
- button_decrease.connect_clicked(clone!(@weak button_increase =>
+ button_decrease.connect_clicked(clone!(@strong button_increase =>
  move |_| {
  number.set(number.get() - 1);
  button_increase.set_label(&number.get().to_string());
  }));
  // ANCHOR_END: callback
 
- // ANCHOR: box_append
  // Add buttons to `gtk_box`
  let gtk_box = gtk::Box::builder()
  .orientation(Orientation::Vertical)
  .build();
  gtk_box.append(&button_increase);
  gtk_box.append(&button_decrease);
- // ANCHOR_END: box_append
 
- // ANCHOR: window_child
  // Create a window
  let window = ApplicationWindow::builder()
  .application(app)
  .title("My GTK App")
  .child(&gtk_box)
  .build();
- // ANCHOR_END: window_child
 
  // Present the window
  window.present();

book/listings/g_object_memory_management/5/main.rs

@@ -0,0 +1,76 @@
+use std::cell::Cell;
+use std::rc::Rc;
+
+use glib::clone;
+use gtk::prelude::*;
+use gtk::{self, glib, Application, ApplicationWindow, Button, Orientation};
+
+const APP_ID: &str = "org.gtk_rs.GObjectMemoryManagement5";
+
+fn main() -> glib::ExitCode {
+ // Create a new application
+ let app = Application::builder().application_id(APP_ID).build();
+
+ // Connect to "activate" signal of `app`
+ app.connect_activate(build_ui);
+
+ // Run the application
+ app.run()
+}
+
+fn build_ui(app: &Application) {
+ // Create two buttons
+ let button_increase = Button::builder()
+ .label("Increase")
+ .margin_top(12)
+ .margin_bottom(12)
+ .margin_start(12)
+ .margin_end(12)
+ .build();
+ let button_decrease = Button::builder()
+ .label("Decrease")
+ .margin_top(12)
+ .margin_bottom(12)
+ .margin_start(12)
+ .margin_end(12)
+ .build();
+
+ // Reference-counted object with inner mutability
+ let number = Rc::new(Cell::new(0));
+
+ // ANCHOR: callback
+ // Connect callbacks
+ // When a button is clicked, `number` and label of the other button will be changed
+ button_increase.connect_clicked(clone!(@weak number, @weak button_decrease =>
+ move |_| {
+ number.set(number.get() + 1);
+ button_decrease.set_label(&number.get().to_string());
+ }));
+ button_decrease.connect_clicked(clone!(@weak button_increase =>
+ move |_| {
+ number.set(number.get() - 1);
+ button_increase.set_label(&number.get().to_string());
+ }));
+ // ANCHOR_END: callback
+
+ // ANCHOR: box_append
+ // Add buttons to `gtk_box`
+ let gtk_box = gtk::Box::builder()
+ .orientation(Orientation::Vertical)
+ .build();
+ gtk_box.append(&button_increase);
+ gtk_box.append(&button_decrease);
+ // ANCHOR_END: box_append
+
+ // ANCHOR: window_child
+ // Create a window
+ let window = ApplicationWindow::builder()
+ .application(app)
+ .title("My GTK App")
+ .child(&gtk_box)
+ .build();
+ // ANCHOR_END: window_child
+
+ // Present the window
+ window.present();
+}