Alternative example structure.

Cargo.toml

@@ -15,6 +15,7 @@ members = [
   "creational/builder",
   "creational/factory-method/maze-game",
   "creational/factory-method/render-dialog",
+  "creational/factory-method/render-dialog-alternative/app",
   "creational/prototype",
   "creational/simple-factory",
   "creational/singleton",

creational/factory-method/README.md

@@ -32,10 +32,13 @@ Ordinary Room: #1
 
 ## Render Dialog
 
-Implementing the Factory Method via **dynamic dispatch**.
+This example shows a GUI framework can organize its classes into independent libraries:
+
+1. The `gui` library defines interfaces for all the components. It has no external dependencies.
+2. The `html_gui` library provides HTML implementation of the base GUI. Depends on `gui`.
+3. The `windows_gui` library provides Windows implementation of the base GUI. Depends on `gui`.
 
-See [Factory Method Java Example](https://refactoring.guru/design-patterns/factory-method/java/example)
-as a reference.
+The `app` is a client application that can use several implementations of the GUI framework, depending on the current environment or configuration. However, most of the `app` code doesn't depend on specific types of GUI elements. All the client code works with GUI elements through abstract interfaces defined by the `gui` lib.
 
 ### How to Run
 

creational/factory-method/render-dialog-alternative/app/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+edition = "2021"
+name = "render-dialog-alternative"
+version = "1.0.0"
+
+[[bin]]
+name = "factory-method-render-dialog"
+path = "main.rs"
+
+[dependencies]
+gui = { path = "../gui", version = "1.0" }
+html_gui = { path = "../html_gui", version = "1.0" }
+windows_gui = { path = "../windows_gui", version = "1.0" }

creational/factory-method/render-dialog-alternative/app/init.rs

@@ -0,0 +1,14 @@
+use gui::dialog::Dialog;
+use html_gui::dialog::HtmlDialog;
+use windows_gui::dialog::WindowsDialog;
+
+pub fn initialize() -> Box<dyn Dialog> {
+    // The dialog type is selected depending on the environment settings or configuration.
+    if cfg!(windows) {
+        println!("-- Windows detected, creating Windows GUI --");
+        return Box::new(WindowsDialog)
+    } else {
+        println!("-- No OS detected, creating the HTML GUI --");
+        return Box::new(HtmlDialog)
+    };
+}

creational/factory-method/render-dialog-alternative/app/main.rs

@@ -0,0 +1,12 @@
+use gui::dialog::Dialog;
+
+mod init;
+use crate::init::initialize;
+
+fn main() {
+    // The rest of the code doesn't depend on specific dialog types, because it works with all
+    // dialog objects via the abstract Dialog trait.
+    let dialog: Box<dyn Dialog> = initialize();
+    dialog.render();
+    dialog.refresh();
+}

creational/factory-method/render-dialog-alternative/gui/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+edition = "2021"
+name = "gui"
+version = "1.0.0"
+
+[lib]
+path = "lib.rs"

creational/factory-method/render-dialog-alternative/gui/button.rs

@@ -0,0 +1,4 @@
+pub trait Button {
+    fn render(&self);
+    fn on_click(&self);
+}

creational/factory-method/render-dialog-alternative/gui/dialog.rs

@@ -0,0 +1,18 @@
+use crate::button::Button;
+
+/// Dialog has a factory method `create_button`.
+///
+/// It creates different buttons depending on a factory implementation.
+pub trait Dialog {
+    fn create_button(&self) -> Box<dyn Button>;
+
+    fn render(&self) {
+        println!("Dialog: Using base render method.");
+        let button = self.create_button();
+        button.render();
+    }
+
+    fn refresh(&self) {
+        println!("Dialog: Using base refresh method.");
+    }
+}

creational/factory-method/render-dialog-alternative/gui/lib.rs

@@ -0,0 +1,2 @@
+pub mod button;
+pub mod dialog;

creational/factory-method/render-dialog-alternative/html_gui/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+edition = "2021"
+name = "html_gui"
+version = "1.0.0"
+
+[lib]
+path = "lib.rs"
+
+[dependencies]
+gui = { path = "../gui", version = "1.0" }

creational/factory-method/render-dialog-alternative/html_gui/button.rs

@@ -0,0 +1,14 @@
+use gui::button::Button;
+
+pub struct HtmlButton;
+
+impl Button for HtmlButton {
+    fn render(&self) {
+        println!("<button>Test Button</button>");
+        self.on_click();
+    }
+
+    fn on_click(&self) {
+        println!("Button: I'm an HTML button!");
+    }
+}

creational/factory-method/render-dialog-alternative/html_gui/dialog.rs

@@ -0,0 +1,12 @@
+use gui::button::Button;
+use gui::dialog::Dialog;
+
+use crate::button::HtmlButton;
+
+pub struct HtmlDialog;
+
+impl Dialog for HtmlDialog {
+    fn create_button(&self) -> Box<dyn Button> {
+        Box::new(HtmlButton)
+    }
+}

creational/factory-method/render-dialog-alternative/html_gui/lib.rs

@@ -0,0 +1,2 @@
+pub mod button;
+pub mod dialog;

creational/factory-method/render-dialog-alternative/windows_gui/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+edition = "2021"
+name = "windows_gui"
+version = "1.0.0"
+
+[lib]
+path = "lib.rs"
+
+[dependencies]
+gui = { path = "../gui", version = "1.0" }

creational/factory-method/render-dialog-alternative/windows_gui/button.rs

@@ -0,0 +1,14 @@
+use gui::button::Button;
+
+pub struct WindowsButton;
+
+impl Button for WindowsButton {
+    fn render(&self) {
+        println!("Drawing a Windows button");
+        self.on_click();
+    }
+
+    fn on_click(&self) {
+        println!("Button: I'm a Windows button!");
+    }
+}

creational/factory-method/render-dialog-alternative/windows_gui/dialog.rs

@@ -0,0 +1,12 @@
+use gui::button::Button;
+use gui::dialog::Dialog;
+
+use crate::button::WindowsButton;
+
+pub struct WindowsDialog;
+
+impl Dialog for WindowsDialog {
+    fn create_button(&self) -> Box<dyn Button> {
+        Box::new(WindowsButton)
+    }
+}

creational/factory-method/render-dialog-alternative/windows_gui/lib.rs

@@ -0,0 +1,2 @@
+pub mod button;
+pub mod dialog;