JemmyFX interactions with a control in a dialog fail intermittently **on Linux** - javafx

Question

My JavaFX application creates a dialog as a second Stage and my JemmyFX tests intermittently fail to click controls in that dialog.
Failures occur at a rate of about 10% on my Ubuntu Linux workstation, but this works flawlessly on Windows.
The proximal cause of the failure seems to be that JemmyFX is clicking the mouse in the wrong places. I dug into this, and the bad click coordinates seem to be caused by incorrect window coordinates coming from the Window object that owns the Scene.
So, I created a minimal application and test that demonstrates the problem, and it actually fails at an even higher rate than my real application (about 50%).
Here is the application:
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.stage.Stage;
public class MySmallApplication extends Application {
public void start(Stage primaryStage) {
class MyDialog extends Stage {
public MyDialog() {
setTitle("My Dialog");
ComboBox comboBox = new ComboBox();
comboBox.getItems().add("apple");
comboBox.getItems().add("pear");
comboBox.getItems().add("banana");
comboBox.setId("click-me");
setScene(new Scene(comboBox));
sizeToScene();
}
}
Button button = new Button("Show Dialog");
button.setOnAction((event) -> {
new MyDialog().showAndWait();
});
primaryStage.setScene(new Scene(button));
primaryStage.setTitle("My Small Application");
primaryStage.show();
}
}
Here is the test:
import javafx.application.Application;
import javafx.scene.control.ComboBox;
import javafx.stage.Window;
import org.jemmy.fx.AppExecutor;
import org.jemmy.fx.SceneDock;
import org.jemmy.fx.control.ComboBoxDock;
import org.jemmy.fx.control.LabeledDock;
import org.jemmy.resources.StringComparePolicy;
import org.junit.BeforeClass;
import org.junit.Test;
import MySmallApplication;
public class WindowBugTest3 {
#BeforeClass
public static void launch() throws InterruptedException {
AppExecutor.executeNoBlock(MySmallApplication.class);
Thread.sleep(1000);
}
#Test
public void testWindowPosition() throws InterruptedException {
SceneDock sceneDock = new SceneDock();
new LabeledDock(
sceneDock.asParent(),
"Show Dialog",
StringComparePolicy.EXACT).mouse().click();
Thread.sleep(1000);
SceneDock dialogSceneDock = new SceneDock(
"My Dialog",
StringComparePolicy.EXACT);
ComboBoxDock comboBoxDock = new ComboBoxDock(
dialogSceneDock.asParent(), "click-me");
comboBoxDock.selector().select("pear");
}
}
I don't really want to develop my tests on Windows.
I observed all of this with recent fetches of JemmyFX (8, 8u, 8u-dev) compiled and run on Java8u101 on Ubuntu 14.04.

Answer 1

It seems that it is a bug in JavaFX (https://bugs.openjdk.java.net/browse/JDK-8166414). It can't be resolved on JemmyFX side.
P.S. It is highly unlikely that it will be fixed in observable time. So I may only suggest to use some ugly workaround like restoring correct dialog coordinates after receiving incorrect ones (e.g. by additional centerOnScreen() on the second invocation of coordinate property listener).