Je veux développer une application qui utilise controlsfx Notifications pour afficher certaines notifications en mode System tray. En mode normal, mon application fonctionne bien et la notification peut être affichée avec succès. Mais lorsque je masque une étape dans la barre d'état système, une exception NullPointerException se produit. Je ne sais pas comment je peux résoudre ce problème.javafx NullPointerException avec controlsfx Notifications componnets
import java.awt.AWTException;
import java.awt.MenuItem;
import java.awt.PopupMenu;
import java.awt.SystemTray;
import java.awt.Toolkit;
import java.awt.TrayIcon;
import java.awt.event.ActionListener;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.event.EventHandler;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.stage.WindowEvent;
public class TryIconNotification extends Application {
private boolean firstTime;
private TrayIcon trayIcon;
@Override
public void start(Stage stage) throws Exception {
firstTime = true;
Parent root = FXMLLoader.load(getClass().getResource("FXMLDocument.fxml"));
Scene scene = new Scene(root);
createTrayIcon(stage);
firstTime = true;
Platform.setImplicitExit(false);
stage.setScene(scene);
stage.show();
}
public void createTrayIcon(final Stage stage) {
if (SystemTray.isSupported()) {
// get the SystemTray instance
SystemTray tray = SystemTray.getSystemTray();
// load an image
java.awt.Image image = null;
image = Toolkit.getDefaultToolkit().getImage("icons\\iconify.png");
stage.setOnCloseRequest(new EventHandler<WindowEvent>() {
@Override
public void handle(WindowEvent t) {
hide(stage);
}
});
// create a action listener to listen for default action executed on the tray icon
final ActionListener closeListener = new ActionListener() {
@Override
public void actionPerformed(java.awt.event.ActionEvent e) {
stage.hide();
}
};
ActionListener showListener = new ActionListener() {
@Override
public void actionPerformed(java.awt.event.ActionEvent e) {
Platform.runLater(new Runnable() {
@Override
public void run() {
stage.show();
}
});
}
};
// create a popup menu
PopupMenu popup = new PopupMenu();
MenuItem showItem = new MenuItem("Open app");
showItem.addActionListener(showListener);
popup.add(showItem);
MenuItem closeItem = new MenuItem("Exit");
closeItem.addActionListener(closeListener);
popup.add(closeItem);
/// ... add other items
// construct a TrayIcon
trayIcon = new TrayIcon(image, "Systray", popup);
// set the TrayIcon properties
trayIcon.addActionListener(showListener);
// ...
// add the tray image
try {
tray.add(trayIcon);
} catch (AWTException e) {
System.err.println(e);
}
// ...
}
}
public void showProgramIsMinimizedMsg() {
//only in first time show the message
if (firstTime) {
trayIcon.displayMessage("System Tray",
"Iconified",
TrayIcon.MessageType.INFO);
firstTime = false;
}
}
private void hide(final Stage stage) {
Platform.runLater(new Runnable() {
@Override
public void run() {
if (SystemTray.isSupported()) {
stage.hide();
showProgramIsMinimizedMsg();
} else {
System.exit(0);
System.out.println("Not Support Sys Tray");
}
}
});
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}
Et ceci est mon contrôleur Classe:
import java.net.URL;
import java.util.ResourceBundle;
import java.util.Timer;
import java.util.TimerTask;
import javafx.application.Platform;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;
import javafx.stage.Stage;
import org.controlsfx.control.Notifications;
public class FXMLDocumentController implements Initializable {
@FXML
private Label label;
@FXML
private void handleButtonAction(ActionEvent event) {
Stage stage = (Stage) label.getScene().getWindow();
stage.hide();
}
public void createNotification() {
Notifications.create()
.text("This is a Notification")
.title("Notifications")
.showInformation();
}
@Override
public void initialize(URL url, ResourceBundle rb) {
Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
Platform.runLater(()->createNotification());
}
}, 5000, 10000);
}
}
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