8296621: Stage steals focus on scene change

Reviewed-by: kcr, mstrauss

Author: Thiago Milczarek Sayao

modules/javafx.graphics/src/main/java/com/sun/javafx/tk/quantum/WindowStage.java

@@ -273,7 +273,6 @@ StageStyle getStyle() {
                 newScene.updateSceneState();
                 return null;
             });
-            requestFocus();
         } else {
             QuantumToolkit.runWithRenderLock(() -> {
                 // platformWindow can be null here, if this window is owned,

tests/system/src/test/java/test/robot/javafx/scene/SceneChangeShouldNotFocusStageTest.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package test.robot.javafx.scene;
+
+import javafx.animation.Animation;
+import javafx.animation.KeyFrame;
+import javafx.animation.Timeline;
+import javafx.application.Application;
+import javafx.application.Platform;
+import javafx.scene.Scene;
+import javafx.scene.control.TextField;
+import javafx.scene.layout.Pane;
+import javafx.stage.Stage;
+import javafx.util.Duration;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import test.util.Util;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class SceneChangeShouldNotFocusStageTest {
+    static Stage stage;
+    static CountDownLatch startupLatch = new CountDownLatch(1);
+
+    @Test
+    void windowShouldRemainIconified() {
+        Util.sleep(2000);
+        assertTrue(stage.isIconified(), "Stage should be iconified");
+    }
+
+    @BeforeAll
+    public static void initFX() throws Exception {
+        Util.launch(startupLatch, TestApp.class);
+    }
+
+    @AfterAll
+    public static void exit() {
+        Util.shutdown(stage);
+    }
+
+    public static class TestApp extends Application {
+        @Override
+        public void start(Stage primaryStage) {
+            stage = primaryStage;
+            Scene scene1 = new Scene(new Pane(new TextField("This is scene1")), 200, 200);
+            Scene scene2 = new Scene(new Pane(new TextField("This is scene2")), 200, 200);
+
+            Timeline tl = new Timeline();
+            tl.setCycleCount(Animation.INDEFINITE);
+            tl.getKeyFrames().addAll(new KeyFrame(Duration.millis(200), e -> stage.setScene(scene1)),
+                    new KeyFrame(Duration.millis(400), e -> stage.setScene(scene2)));
+
+            stage.setOnShown(e -> {
+                tl.play();
+                startupLatch.countDown();
+            });
+
+            stage.setIconified(true);
+            stage.show();
+        }
+    }
+
+    public static void waitForLatch(CountDownLatch latch, int seconds, String msg) throws Exception {
+        assertTrue(latch.await(seconds, TimeUnit.SECONDS), "Timeout: " + msg);
+    }
+}