lesson2

.idea/gradle.xml

@@ -10,6 +10,7 @@
           <set>
             <option value="$PROJECT_DIR$" />
             <option value="$PROJECT_DIR$/lesson1" />
+            <option value="$PROJECT_DIR$/lesson2" />
           </set>
         </option>
       </GradleProjectSettings>

lesson2/build.gradle.kts

@@ -0,0 +1,23 @@
+plugins {
+    kotlin("jvm")
+}
+
+group = "com.msksbr.jfxLearn"
+version = "unspecified"
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testImplementation(kotlin("test"))
+}
+
+tasks.test {
+    useJUnitPlatform()
+}
+kotlin {
+    jvmToolchain(17)
+}
+
+application.mainClass.set("com.msksbr.jfxLearn.lesson2.MainKt")

lesson2/src/main/kotlin/Main.kt

@@ -0,0 +1,56 @@
+/**
+ * Lesson: Application
+ *
+ * 1. The Application class serves as the entry point for JavaFX applications.
+ * 2. The main method initiates the JavaFX runtime via Application.launch(String... args).
+ * 3. When launch() is called without arguments, the application lifecycle follows:
+ *    - init(): Initialization phase
+ *    - start(): Primary stage setup
+ *    - stop(): Cleanup upon application exit
+ */
+
+package com.msksbr.jfxLearn.lesson2
+
+import javafx.application.Application
+import javafx.scene.Scene
+import javafx.stage.Stage
+import javafx.scene.control.Button
+import javafx.scene.layout.BorderPane
+
+class MainApplication : Application() {
+    override fun start(stage: Stage) {
+        println("we are in start method")
+        // Extension Exercises: create a button, when it clicked, open a website via browser
+        val button = Button("open website")
+        button.setOnAction {
+            hostServices.showDocument("https://msksbr.com")
+        }
+        val borderPane = BorderPane(button)
+        val scene = Scene(borderPane, 300.0, 300.0)
+
+        stage.scene = scene
+        stage.title = "JavaFX Application"
+        stage.show()
+    }
+
+    override fun init() {
+        // what can we do in init method?
+        // 1. connect database
+        // 2, create a new thread
+        // ...
+        println("we are in init method")
+    }
+
+    override fun stop() {
+        // what can we do in stop method?
+        // 1. close database connection
+        // 2. close a thread
+        // 3. clean resources
+        // ...
+        println("we are in stop method")
+    }
+}
+
+fun main(args: Array<String>) {
+    Application.launch(MainApplication::class.java, *args)
+}

settings.gradle.kts

@@ -1,2 +1,3 @@
 rootProject.name = "jfx-learn"
-include("lesson1")
+include("lesson1")
+include("lesson2")