add drag sort

src/main/java/com/imyeyu/hosts/ui/components/HostTable.java

@@ -10,16 +10,22 @@ import com.imyeyu.lang.multi.ResourcesMultilingual;
 import javafx.beans.binding.DoubleBinding;
 import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.StringProperty;
+import javafx.collections.ObservableList;
 import javafx.geometry.Insets;
 import javafx.geometry.Pos;
 import javafx.scene.control.Button;
 import javafx.scene.control.CheckBox;
 import javafx.scene.control.TableCell;
 import javafx.scene.control.TableColumn;
+import javafx.scene.control.TableRow;
 import javafx.scene.control.TableView;
 import javafx.scene.control.TextField;
 import javafx.scene.control.cell.PropertyValueFactory;
+import javafx.scene.input.ClipboardContent;
+import javafx.scene.input.Dragboard;
+import javafx.scene.input.MouseEvent;
 import javafx.scene.input.ScrollEvent;
+import javafx.scene.input.TransferMode;
 import lombok.RequiredArgsConstructor;
 
 /**
@@ -31,7 +37,10 @@ import lombok.RequiredArgsConstructor;
 @RequiredArgsConstructor
 public class HostTable extends TableView<Host> implements TimiFXUI {
 
+	private static final String DRAG_INDEX_KEY = "host-table-row-index";
+
 	private final ResourcesMultilingual multilingual;
+	private int dragSourceIndex = -1;
 
 	@PostConstruct
 	private void postConstruct() {
@@ -78,6 +87,10 @@ public class HostTable extends TableView<Host> implements TimiFXUI {
 			}
 		});
 		getColumns().add(activated);
+
+		TableColumn<Host, Void> drag = createDragColumn();
+		getColumns().add(drag);
+
 		// IP
 		TableColumn<Host, String> ip = new TableColumn<>("IP");
 		ip.setCellValueFactory(new PropertyValueFactory<>("ip"));
@@ -245,6 +258,7 @@ public class HostTable extends TableView<Host> implements TimiFXUI {
 
 		DoubleBinding db = widthProperty().subtract(8);
 		db = db.subtract(activated.widthProperty());
+		db = db.subtract(drag.widthProperty());
 		db = db.subtract(ip.widthProperty());
 		db = db.subtract(description.widthProperty());
 		db = db.subtract(delete.widthProperty());
@@ -256,5 +270,117 @@ public class HostTable extends TableView<Host> implements TimiFXUI {
 
 		// 滚动时编辑区主动失去焦点
 		addEventFilter(ScrollEvent.ANY, e -> requestFocus());
+		setRowFactory(table -> createDraggableRow());
 	}
-}
+
+	/**
+	 * 创建拖动排序列。
+	 *
+	 * @return 拖动排序列
+	 */
+	private TableColumn<Host, Void> createDragColumn() {
+		TableColumn<Host, Void> drag = new TableColumn<>("");
+		drag.setPrefWidth(40);
+		drag.setSortable(false);
+		drag.setResizable(false);
+		drag.setReorderable(false);
+		drag.setCellFactory(cell -> new TableCell<>() {
+
+			private final Button dragButton = new Button("::");
+
+			{
+				dragButton.getStyleClass().add(CSS.BORDER_N);
+				dragButton.setFocusTraversable(false);
+				dragButton.setOnDragDetected(this::startRowDrag);
+				setAlignment(Pos.CENTER);
+			}
+
+			@Override
+			protected void updateItem(Void item, boolean empty) {
+				super.updateItem(item, empty);
+				if (empty || getTableRow() == null || getTableRow().getItem() == null) {
+					setGraphic(null);
+				} else {
+					setGraphic(dragButton);
+				}
+			}
+
+			/**
+			 * 从拖动按钮发起行拖拽。
+			 *
+			 * @param event 鼠标事件
+			 */
+			private void startRowDrag(MouseEvent event) {
+				TableRow<Host> row = getTableRow();
+				if (row == null || row.isEmpty()) {
+					return;
+				}
+				dragSourceIndex = row.getIndex();
+				Dragboard dragboard = row.startDragAndDrop(TransferMode.MOVE);
+				ClipboardContent content = new ClipboardContent();
+				content.putString(DRAG_INDEX_KEY.formatted());
+				dragboard.setContent(content);
+				event.consume();
+			}
+		});
+		return drag;
+	}
+
+	/**
+	 * 创建支持拖动排序的表格行。
+	 *
+	 * @return 表格行
+	 */
+	private TableRow<Host> createDraggableRow() {
+		TableRow<Host> row = new TableRow<>();
+		row.setOnDragOver(event -> {
+			if (dragSourceIndex < 0 || row.getIndex() == dragSourceIndex) {
+				return;
+			}
+			if (event.getDragboard().hasString()) {
+				event.acceptTransferModes(TransferMode.MOVE);
+				event.consume();
+			}
+		});
+		row.setOnDragDropped(event -> {
+			if (dragSourceIndex < 0) {
+				return;
+			}
+			int targetIndex = row.isEmpty() ? getItems().size() : row.getIndex();
+			moveItem(dragSourceIndex, targetIndex);
+			event.setDropCompleted(true);
+			event.consume();
+		});
+		row.setOnDragDone(event -> dragSourceIndex = -1);
+		return row;
+	}
+
+	/**
+	 * 调整条目顺序。
+	 *
+	 * @param fromIndex 原索引
+	 * @param toIndex   目标索引
+	 */
+	private void moveItem(int fromIndex, int toIndex) {
+		ObservableList<Host> items = getItems();
+		if (fromIndex < 0 || items.size() <= fromIndex) {
+			return;
+		}
+		if (toIndex < 0) {
+			toIndex = 0;
+		}
+		if (items.size() < toIndex) {
+			toIndex = items.size();
+		}
+		if (fromIndex == toIndex) {
+			return;
+		}
+		Host movedItem = items.remove(fromIndex);
+		if (fromIndex < toIndex) {
+			toIndex--;
+		}
+		items.add(toIndex, movedItem);
+		getSelectionModel().clearAndSelect(toIndex);
+		scrollTo(toIndex);
+	}
+}