Ask to save the current layout when closing shuffleboard

api/src/main/resources/edu/wpi/first/shuffleboard/api/base.css

@@ -235,3 +235,11 @@
     /* Bring the content to all edges */
     -fx-padding: 0; /* 10 0 0 10 */
 }
+
+.dialog-pane .header-panel {
+    -fx-background-color: -swatch-500;
+}
+
+.dialog-pane .header-panel .label {
+    -fx-text-fill: white;
+}

app/src/main/java/edu/wpi/first/shuffleboard/app/MainWindowController.java

@@ -1,13 +1,11 @@
 package edu.wpi.first.shuffleboard.app;
 
-import com.google.common.collect.ArrayListMultimap;
-import com.google.common.collect.Multimap;
-import com.google.common.io.Files;
-
 import edu.wpi.first.shuffleboard.api.DashboardMode;
 import edu.wpi.first.shuffleboard.api.components.SourceTreeTable;
+import edu.wpi.first.shuffleboard.api.components.WidgetPropertySheet;
 import edu.wpi.first.shuffleboard.api.dnd.DataFormats;
 import edu.wpi.first.shuffleboard.api.plugin.Plugin;
+import edu.wpi.first.shuffleboard.api.prefs.FlushableProperty;
 import edu.wpi.first.shuffleboard.api.sources.DataSource;
 import edu.wpi.first.shuffleboard.api.sources.SourceEntry;
 import edu.wpi.first.shuffleboard.api.sources.recording.Recorder;
@@ -19,13 +17,15 @@
 import edu.wpi.first.shuffleboard.app.components.DashboardTab;
 import edu.wpi.first.shuffleboard.app.components.DashboardTabPane;
 import edu.wpi.first.shuffleboard.app.components.WidgetGallery;
-import edu.wpi.first.shuffleboard.api.components.WidgetPropertySheet;
 import edu.wpi.first.shuffleboard.app.json.JsonBuilder;
 import edu.wpi.first.shuffleboard.app.plugin.PluginLoader;
 import edu.wpi.first.shuffleboard.app.prefs.AppPreferences;
-import edu.wpi.first.shuffleboard.api.prefs.FlushableProperty;
 import edu.wpi.first.shuffleboard.app.sources.recording.Playback;
 
+import com.google.common.collect.ArrayListMultimap;
+import com.google.common.collect.Multimap;
+import com.google.common.io.Files;
+
 import org.fxmisc.easybind.EasyBind;
 
 import java.io.File;
@@ -68,6 +68,8 @@
 import javafx.stage.Modality;
 import javafx.stage.Stage;
 import javafx.stage.StageStyle;
+import javafx.stage.Window;
+import javafx.stage.WindowEvent;
 
 import static edu.wpi.first.shuffleboard.api.components.SourceTreeTable.alphabetical;
 import static edu.wpi.first.shuffleboard.api.components.SourceTreeTable.branchesFirst;
@@ -292,10 +294,17 @@ public void setDashboard(DashboardTabPane dashboard) {
     centerSplitPane.getItems().add(dashboard);
   }
 
+  /**
+   * Closes from interacting with the "Close" menu item.
+   */
   @FXML
   public void close() {
     log.info("Exiting app");
-    System.exit(0);
+
+    // Attempt to close the main window. This lets window closing handlers run. Calling System.exit() or Platform.exit()
+    // will more-or-less immediately terminate the application without calling these handlers.
+    Window window = root.getScene().getWindow();
+    window.fireEvent(new WindowEvent(window, WindowEvent.WINDOW_CLOSE_REQUEST));
   }
 
   /**

app/src/main/java/edu/wpi/first/shuffleboard/app/Shuffleboard.java

@@ -28,6 +28,8 @@
 import javafx.application.Platform;
 import javafx.fxml.FXMLLoader;
 import javafx.scene.Scene;
+import javafx.scene.control.Alert;
+import javafx.scene.control.ButtonType;
 import javafx.scene.layout.Pane;
 import javafx.stage.Screen;
 import javafx.stage.Stage;
@@ -90,6 +92,30 @@ public void start(Stage primaryStage) throws IOException {
     primaryStage.setMinHeight(480);
     primaryStage.setWidth(Screen.getPrimary().getVisualBounds().getWidth());
     primaryStage.setHeight(Screen.getPrimary().getVisualBounds().getHeight());
+    primaryStage.setOnCloseRequest(closeEvent -> {
+      if (!AppPreferences.getInstance().isConfirmExit()) {
+        // Don't show the confirmation dialog, just exit
+        return;
+      }
+      Alert alert = new Alert(Alert.AlertType.CONFIRMATION);
+      alert.setTitle("Save layout");
+      alert.getDialogPane().getScene().getStylesheets().setAll(mainPane.getStylesheets());
+      alert.getButtonTypes().setAll(ButtonType.YES, ButtonType.NO, ButtonType.CANCEL);
+      alert.getDialogPane().setHeaderText("Save the current layout before closing?");
+      alert.showAndWait().ifPresent(bt -> {
+        if (bt == ButtonType.YES) {
+          try {
+            mainWindowController.save();
+          } catch (IOException ex) {
+            logger.log(Level.WARNING, "Could not save the layout", ex);
+          }
+        } else if (bt == ButtonType.CANCEL) {
+          // cancel the close request by consuming the event
+          closeEvent.consume();
+        }
+        // Don't need to check for NO because it just lets the window close normally
+      });
+    });
     primaryStage.show();
     Time.setStartTime(Time.now());
   }

app/src/main/java/edu/wpi/first/shuffleboard/app/prefs/AppPreferences.java

@@ -18,8 +18,7 @@
 import javafx.beans.property.SimpleObjectProperty;
 
 /**
- * Contains the user preferences for the app. These preferences are user-specific and are saved
- * to the users home directory and are not contained in save files.
+ * Contains the user preferences for the app. These preferences are user-specific and are not contained in save files.
  */
 public final class AppPreferences {
 
@@ -28,6 +27,8 @@ public final class AppPreferences {
   private final Property<File> saveFile = new SimpleObjectProperty<>(this, "saveFile", null);
   private final BooleanProperty autoLoadLastSaveFile =
       new SimpleBooleanProperty(this, "automaticallyLoadLastSaveFile", true);
+  private final BooleanProperty confirmExit =
+      new SimpleBooleanProperty(this, "showConfirmationDialogWhenExiting", true);
 
   @VisibleForTesting
   static AppPreferences instance = new AppPreferences();
@@ -41,11 +42,13 @@ public AppPreferences() {
     PreferencesUtils.read(defaultTileSize, preferences);
     PreferencesUtils.read(saveFile, preferences, File::new);
     PreferencesUtils.read(autoLoadLastSaveFile, preferences);
+    PreferencesUtils.read(confirmExit, preferences);
 
     theme.addListener(__ -> PreferencesUtils.save(theme, preferences, Theme::getName));
     defaultTileSize.addListener(__ -> PreferencesUtils.save(defaultTileSize, preferences));
     saveFile.addListener(__ -> PreferencesUtils.save(saveFile, preferences, File::getAbsolutePath));
     autoLoadLastSaveFile.addListener(__ -> PreferencesUtils.save(autoLoadLastSaveFile, preferences));
+    confirmExit.addListener(__ -> PreferencesUtils.save(confirmExit, preferences));
   }
 
   public static AppPreferences getInstance() {
@@ -59,7 +62,8 @@ public ImmutableList<Property<?>> getProperties() {
     return ImmutableList.of(
         theme,
         defaultTileSize,
-        autoLoadLastSaveFile
+        autoLoadLastSaveFile,
+        confirmExit
     );
   }
 
@@ -110,4 +114,16 @@ public BooleanProperty autoLoadLastSaveFileProperty() {
   public void setAutoLoadLastSaveFile(boolean autoLoadLastSaveFile) {
     this.autoLoadLastSaveFile.set(autoLoadLastSaveFile);
   }
+
+  public boolean isConfirmExit() {
+    return confirmExit.get();
+  }
+
+  public BooleanProperty confirmExitProperty() {
+    return confirmExit;
+  }
+
+  public void setConfirmExit(boolean confirmExit) {
+    this.confirmExit.set(confirmExit);
+  }
 }