Dynamisk kontekst-meny for liste-elementer (#11)

todolist/fxui/src/main/java/todolist/ui/TodoListController.java

@@ -8,13 +8,16 @@ import java.util.function.Predicate;
 import javafx.fxml.FXML;
 import javafx.scene.Node;
 import javafx.scene.control.Button;
+import javafx.scene.control.ContextMenu;
 import javafx.scene.control.ListCell;
 import javafx.scene.control.ListView;
+import javafx.scene.control.MenuItem;
 import javafx.scene.control.TextField;
 import javafx.util.Callback;
 import todolist.core.TodoItem;
 import todolist.core.TodoList;
 import todolist.core.TodoListListener;
+import todolist.ui.util.DynamicContextMenu;
 
 /**
  * Controller for a TodoList.
@@ -42,6 +45,8 @@ public class TodoListController {
     return todoList;
   }
 
+  ContextMenu cm;
+
   /**
    * Sets the TodoList managed by this controller.
    * The corresponding views will be updated.
@@ -82,6 +87,7 @@ public class TodoListController {
     todoItemsView.setCellFactory(listView -> {
       TodoItemListCell listCell = new TodoItemListCell();
       dragHandler.registerHandlers(listCell);
+      listCell.setContextMenu(new DynamicContextMenu(() -> createTodoListCellMenuItems(listCell)));
       return listCell;
     });
     todoItemsView.getSelectionModel().selectedItemProperty()
@@ -89,6 +95,19 @@ public class TodoListController {
     todoItemsView.setEditable(true);
   }
 
+  private Collection<MenuItem> createTodoListCellMenuItems(TodoItemListCell listCell) {
+    TodoItem todoItem = listCell.getItem();
+    MenuItem toggleMenuItem = new MenuItem(todoItem.isChecked() ? "Uncheck" : "Check");
+    toggleMenuItem.setOnAction(event -> {
+      todoItem.setChecked(! todoItem.isChecked());
+    });
+    MenuItem deleteMenuItem = new MenuItem("Delete");
+    deleteMenuItem.setOnAction(event -> {
+      deleteTodoItem(todoItem, listCell.getIndex());
+    });
+    return List.of(toggleMenuItem, deleteMenuItem);
+  }
+
   private Function<TodoList, Collection<TodoItem>> todoItemsProvider = TodoList::getTodoItems;
 
   public void setTodoItemsProvider(Function<TodoList, Collection<TodoItem>> todoItemsProvider) {
@@ -163,11 +182,15 @@ public class TodoListController {
     int index = todoItemsView.getSelectionModel().getSelectedIndex();
     TodoItem item = todoItemsView.getItems().get(index);
     if (item != null) {
-      getTodoList().removeTodoItem(item);
-      selectWithinBounds(index);
+      deleteTodoItem(item, index);
     }
   }
 
+  private void deleteTodoItem(TodoItem item, int index) {
+    getTodoList().removeTodoItem(item);
+    selectWithinBounds(index);
+  }
+
   private int selectWithinBounds(int index) {
     int maxIndex = todoItemsView.getItems().size() - 1;
     if (index > maxIndex) {

todolist/fxui/src/main/java/todolist/ui/util/DynamicContextMenu.java

+package todolist.ui.util;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.function.Supplier;
+
+import javafx.geometry.Side;
+import javafx.scene.Node;
+import javafx.scene.control.ContextMenu;
+import javafx.scene.control.MenuItem;
+
+/**
+ * ContextMenu that populates the list of menu items when it is about to be shown, rather than in
+ * advance.
+ */
+public class DynamicContextMenu extends ContextMenu {
+
+  private MenuItem dummyItem = new MenuItem("Populating ...");
+
+  public DynamicContextMenu() {
+    resetItems();
+  }
+
+  public DynamicContextMenu(Supplier<Collection<MenuItem>> menuItemsSupplier) {
+    setMenuItemsSupplier(menuItemsSupplier);
+  }
+
+  private void resetItems() {
+    getItems().setAll(dummyItem);
+  }
+
+  private Supplier<Collection<MenuItem>> menuItemsSupplier;
+
+  public void setMenuItemsSupplier(Supplier<Collection<MenuItem>> menuItemsSupplier) {
+    this.menuItemsSupplier = menuItemsSupplier;
+  }
+
+  protected Collection<MenuItem> getDynamicItems() {
+    return menuItemsSupplier != null ? menuItemsSupplier.get() : Collections.emptyList();
+  }
+
+  protected void populateItems() {
+    getItems().setAll(getDynamicItems());
+  }
+
+  @Override
+  public void show(Node anchor, Side side, double dx, double dy) {
+    populateItems();
+    super.show(anchor, side, dx, dy);
+  }
+
+  @Override
+  public void show(Node anchor, double screenX, double screenY) {
+    populateItems();
+    super.show(anchor, screenX, screenY);
+  }
+
+  @Override
+  public void hide() {
+    super.hide();
+    resetItems();
+  }
+}