Add welcome screen to JabRef GUI that displays when no database/library is open

CHANGELOG.md

@@ -34,6 +34,7 @@ Note that this project **does not** adhere to [Semantic Versioning](https://semv
 - We added a different background color to the search bar to indicate when the search syntax is wrong. [#11658](https://github.com/JabRef/jabref/pull/11658)
 - We added a setting which always adds the literal "Cited on pages" text before each JStyle citation. [#11691](https://github.com/JabRef/jabref/pull/11732)
 - We added a new plain citation parser that uses LLMs. [#11825](https://github.com/JabRef/jabref/issues/11825)
+- We added a welcome screen that displays when no database is open [koppor#96](https://github.com/koppor/jabref/issues/96)
 - We added support for modifier keys when dropping a file on an entry in the main table. [#12001](https://github.com/JabRef/jabref/pull/12001)
 - We added an importer for SSRN URLs. [#12021](https://github.com/JabRef/jabref/pull/12021)
 - We added a compare button to the duplicates in the citation relations tab to open the "Possible duplicate entries" window. [#11192](https://github.com/JabRef/jabref/issues/11192)

src/main/java/org/jabref/gui/Base.css

@@ -1732,5 +1732,20 @@ We want to have a look that matches our icons in the tool-bar */
     -fx-effect: dropshadow(three-pass-box, rgba(0, 0, 0, 0.6), 8, 0.0, 0, 0);
 }
 
+/* Welcome Page Styles */
+.welcome-label {
+    -fx-font-size: 40px;
+    -fx-text-fill: -jr-theme-text;
+    -fx-font-family: "Arial";
+}
+
+.welcome-hyperlink {
+    -fx-font-size: 22px;
+    -fx-text-fill: -jr-theme;
+}
+
+.welcome-hyperlink:visited {
+    -fx-text-fill: -jr-theme;
+}
 
 /* endregion */

src/main/java/org/jabref/gui/frame/JabRefFrame.java

@@ -21,6 +21,7 @@
 import javafx.scene.control.TabPane;
 import javafx.scene.input.KeyEvent;
 import javafx.scene.layout.BorderPane;
+import javafx.scene.layout.StackPane;
 import javafx.scene.layout.VBox;
 import javafx.stage.Stage;
 
@@ -45,6 +46,7 @@
 import org.jabref.gui.sidepane.SidePane;
 import org.jabref.gui.sidepane.SidePaneType;
 import org.jabref.gui.undo.CountingUndoManager;
+import org.jabref.gui.util.WelcomePage;
 import org.jabref.logic.UiCommand;
 import org.jabref.logic.ai.AiService;
 import org.jabref.logic.journals.JournalAbbreviationRepository;
@@ -99,6 +101,9 @@ public class JabRefFrame extends BorderPane implements LibraryTabContainer, UiMe
 
     private Subscription dividerSubscription;
 
+    private final WelcomePage welcomePage;
+    private final StackPane contentPane = new StackPane();  // Holds both WelcomePage and SplitPane
+
     public JabRefFrame(Stage mainStage,
                        DialogService dialogService,
                        FileUpdateMonitor fileUpdateMonitor,
@@ -120,6 +125,19 @@ public JabRefFrame(Stage mainStage,
         this.clipBoardManager = clipBoardManager;
         this.taskExecutor = taskExecutor;
 
+        this.welcomePage = new WelcomePage(
+                this,
+                preferences,
+                aiService,
+                dialogService,
+                stateManager,
+                fileUpdateMonitor,
+                entryTypesManager,
+                undoManager,
+                clipBoardManager,
+                taskExecutor
+        );
+
         setId("frame");
 
         // Create components
@@ -181,10 +199,13 @@ public JabRefFrame(Stage mainStage,
             }
         });
 
+        // Initialize layout and bindings
         initLayout();
         initKeyBindings();
         frameDndHandler.initDragAndDrop();
         initBindings();
+        bindDatabaseChanges();
+        updateContent();
     }
 
     private void initLayout() {
@@ -224,11 +245,25 @@ private void initLayout() {
         setTop(head);
 
         splitPane.getItems().addAll(tabbedPane);
+        contentPane.getChildren().addAll(welcomePage, splitPane);
         SplitPane.setResizableWithParent(sidePane, false);
         sidePane.widthProperty().addListener(c -> updateSidePane());
         sidePane.getChildren().addListener((InvalidationListener) c -> updateSidePane());
-        updateSidePane();
-        setCenter(splitPane);
+        setCenter(contentPane);
+        updateSidePane();  // Ensure layout is consistent on load
+        updateContent();
+    }
+
+    private void updateContent() {
+        boolean hasOpenDatabases = !stateManager.getOpenDatabases().isEmpty();
+
+        // Toggle visibility between welcome page and tabbed pane
+        welcomePage.setVisible(!hasOpenDatabases);
+        splitPane.setVisible(hasOpenDatabases);
+    }
+
+    private void bindDatabaseChanges() {
+        stateManager.getOpenDatabases().addListener((InvalidationListener) obs -> Platform.runLater(this::updateContent));
     }
 
     private void updateSidePane() {

src/main/java/org/jabref/gui/util/WelcomePage.java

@@ -0,0 +1,56 @@
+package org.jabref.gui.util;
+
+import javafx.geometry.Pos;
+import javafx.scene.control.Hyperlink;
+import javafx.scene.control.Label;
+import javafx.scene.layout.VBox;
+
+import org.jabref.gui.ClipBoardManager;
+import org.jabref.gui.DialogService;
+import org.jabref.gui.StateManager;
+import org.jabref.gui.frame.JabRefFrame;
+import org.jabref.gui.importer.NewDatabaseAction;
+import org.jabref.gui.importer.actions.OpenDatabaseAction;
+import org.jabref.gui.preferences.GuiPreferences;
+import org.jabref.gui.undo.CountingUndoManager;
+import org.jabref.logic.ai.AiService;
+import org.jabref.logic.l10n.Localization;
+import org.jabref.logic.util.TaskExecutor;
+import org.jabref.model.entry.BibEntryTypesManager;
+import org.jabref.model.util.FileUpdateMonitor;
+
+/**
+ * A simple Welcome Page for the JabRef application.
+ */
+public class WelcomePage extends VBox {
+
+    public WelcomePage(JabRefFrame frame,
+                       GuiPreferences preferences,
+                       AiService aiService,
+                       DialogService dialogService,
+                       StateManager stateManager,
+                       FileUpdateMonitor fileUpdateMonitor,
+                       BibEntryTypesManager entryTypesManager,
+                       CountingUndoManager undoManager,
+                       ClipBoardManager clipBoardManager,
+                       TaskExecutor taskExecutor) {
+
+        setAlignment(Pos.CENTER);
+        setSpacing(10);
+
+        Label welcomeLabel = new Label(Localization.lang("Welcome to JabRef!"));
+        welcomeLabel.getStyleClass().add("welcome-label");
+
+        Hyperlink newLibrary = new Hyperlink(Localization.lang("Open a New Library"));
+        newLibrary.getStyleClass().add("welcome-hyperlink");
+        newLibrary.setOnAction(e -> new NewDatabaseAction(frame, preferences).execute());
+
+        Hyperlink openLibrary = new Hyperlink(Localization.lang("or open an Existing Library"));
+        openLibrary.getStyleClass().add("welcome-hyperlink");
+        openLibrary.setOnAction(e -> new OpenDatabaseAction(frame, preferences, aiService, dialogService,
+                stateManager, fileUpdateMonitor, entryTypesManager, undoManager, clipBoardManager,
+                taskExecutor).execute());
+
+        getChildren().addAll(welcomeLabel, newLibrary, openLibrary);
+    }
+}

src/main/resources/l10n/JabRef_en.properties

@@ -2803,3 +2803,7 @@ Citation\ Entry=Citation Entry
 
 File\ Move\ Errors=File Move Errors
 Could\ not\ move\ file\ %0.\ Please\ close\ this\ file\ and\ retry.=Could not move file %0. Please close this file and retry.
+
+Open\ a\ New\ Library=Open a New Library
+Welcome\ to\ JabRef!=Welcome to JabRef!
+or\ open\ an\ Existing\ Library=or open an Existing Library