From 4d2170683527213dc2aef3ad67fdd8a562af1a74 Mon Sep 17 00:00:00 2001
From: Dirk Lemmermann <dlemmermann@gmail.com>
Date: Wed, 4 Dec 2024 14:04:13 +0100
Subject: [PATCH] Added new SimplePagingListView control.

---
 .../gemsfx/demo/SimplePagingListViewApp.java  | 42 ++++++++++++
 .../com/dlsc/gemsfx/SimplePagingListView.java | 67 +++++++++++++++++++
 2 files changed, 109 insertions(+)
 create mode 100644 gemsfx-demo/src/main/java/com/dlsc/gemsfx/demo/SimplePagingListViewApp.java
 create mode 100644 gemsfx/src/main/java/com/dlsc/gemsfx/SimplePagingListView.java

diff --git a/gemsfx-demo/src/main/java/com/dlsc/gemsfx/demo/SimplePagingListViewApp.java b/gemsfx-demo/src/main/java/com/dlsc/gemsfx/demo/SimplePagingListViewApp.java
new file mode 100644
index 00000000..f918b63d
--- /dev/null
+++ b/gemsfx-demo/src/main/java/com/dlsc/gemsfx/demo/SimplePagingListViewApp.java
@@ -0,0 +1,42 @@
+package com.dlsc.gemsfx.demo;
+
+import com.dlsc.gemsfx.SimplePagingListView;
+import javafx.application.Application;
+import javafx.geometry.Insets;
+import javafx.scene.Scene;
+import javafx.scene.control.Button;
+import javafx.scene.layout.VBox;
+import javafx.stage.Stage;
+import org.scenicview.ScenicView;
+
+public class SimplePagingListViewApp extends Application {
+
+    @Override
+    public void start(Stage stage) {
+        SimplePagingListView<String> pagingListView = new SimplePagingListView<>();
+        pagingListView.setPrefWidth(400);
+        for (int i = 0; i < 200; i++) {
+            pagingListView.getItems().add("Item " + (i + 1));
+        }
+
+        Button scenicView = new Button("Scenic View");
+        scenicView.setOnAction(evt -> ScenicView.show(scenicView.getScene()));
+
+        VBox box = new VBox(20, pagingListView, new PagingControlsSettingsView(pagingListView), scenicView);
+        box.setPadding(new Insets(20));
+
+        Scene scene = new Scene(box);
+
+        scene.focusOwnerProperty().addListener(it -> System.out.println(scene.getFocusOwner()));
+
+        stage.setTitle("Simple Paging List View");
+        stage.setScene(scene);
+        stage.sizeToScene();
+        stage.centerOnScreen();
+        stage.show();
+    }
+
+    public static void main(String[] args) {
+        launch();
+    }
+}
diff --git a/gemsfx/src/main/java/com/dlsc/gemsfx/SimplePagingListView.java b/gemsfx/src/main/java/com/dlsc/gemsfx/SimplePagingListView.java
new file mode 100644
index 00000000..e2c83f65
--- /dev/null
+++ b/gemsfx/src/main/java/com/dlsc/gemsfx/SimplePagingListView.java
@@ -0,0 +1,67 @@
+package com.dlsc.gemsfx;
+
+import javafx.beans.Observable;
+import javafx.beans.property.ListProperty;
+import javafx.beans.property.SimpleListProperty;
+import javafx.collections.FXCollections;
+import javafx.collections.ObservableList;
+
+/**
+ * A simple version of the paging list view that is completely based on a list of tiems, just like a normal
+ * list view would be.
+ *
+ * @param <T> the type of items to show in the list view
+ */
+public class SimplePagingListView<T> extends PagingListView<T> {
+
+    private boolean internal;
+
+    /**
+     * Constructs a new list view and sets a loader that uses the data list.
+     */
+    public SimplePagingListView() {
+        setLoader(lv -> {
+            int pageSize = getPageSize();
+            int index = getPage() * pageSize;
+            return getItems().subList(index, Math.min(index + pageSize, getItems().size() - 1));
+        });
+
+        loaderProperty().addListener(it -> {
+            throw new UnsupportedOperationException("a custom loader can not be used for this list view");
+        });
+
+        totalItemCountProperty().addListener(it -> {
+            if (!internal) {
+                throw new UnsupportedOperationException("the total item count can not be explicitly changed for this list view");
+
+            }
+        });
+
+        items.addListener((Observable it) -> {
+            ObservableList list = getItems();
+            if (list != null) {
+                internal = true;
+                try {
+                    setTotalItemCount(list.size());
+                    setPage(Math.min(getTotalItemCount() / getPageSize(), getPage()));
+                } finally {
+                    internal = false;
+                }
+            }
+        });
+    }
+
+    private final ListProperty<T> items = new SimpleListProperty<>(this, "items", FXCollections.observableArrayList());
+
+    public final ObservableList<T> getItems() {
+        return items.get();
+    }
+
+    public final ListProperty<T> itemsProperty() {
+        return items;
+    }
+
+    public final void setItems(ObservableList<T> items) {
+        this.items.set(items);
+    }
+}