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請看下面的例子：複選框內的TableCell打破了遍歷順序
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.CheckBox;
import javafx.scene.control.TextField;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class TestCheckBoxTab extends Application {
public void start (Stage stage) {
HBox root = new HBox();
root.getChildren().addAll(new TextField(), new TextField(), new CheckBox(), new TextField());
stage.setScene(new Scene(root));
stage.show();
}
public static void main (String[] args) {
launch();
}
}
在這裏，您可以輕鬆地使用Tab鍵和Shift + Tab命令通過不同的控制來遍歷，它工作正常。
但是，如果您在TableView中的表單元格內具有相同的控件，則CheckBox會中斷遍歷順序。這表現在下面的例子：
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.CheckBox;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.TextField;
import javafx.stage.Stage;
public class AlwaysEditableTable extends Application {
public void start(Stage stage) {
TableView<ObservableList<StringProperty>> table = new TableView<>();
table.setEditable(true);
table.getSelectionModel().setCellSelectionEnabled(true);
table.setPrefWidth(505);
// Dummy columns
ObservableList<String> columns = FXCollections.observableArrayList("Column1", "Column2", "Column3", "Column4",
"Column5");
// Dummy data
ObservableList<StringProperty> row1 = FXCollections.observableArrayList(new SimpleStringProperty("Cell1"),
new SimpleStringProperty("Cell2"), new SimpleStringProperty("0"), new SimpleStringProperty("Cell4"),
new SimpleStringProperty("1"));
ObservableList<ObservableList<StringProperty>> data = FXCollections.observableArrayList();
data.add(row1);
for (int i = 0; i < columns.size(); i++) {
final int j = i;
TableColumn<ObservableList<StringProperty>, String> col = new TableColumn<>(columns.get(i));
col.setCellValueFactory(param -> param.getValue().get(j));
col.setPrefWidth(100);
if (i == 2 || i == 4) {
col.setCellFactory(e -> new CheckBoxCell(j));
} else {
col.setCellFactory(e -> new AlwaysEditingCell(j));
}
table.getColumns().add(col);
}
table.setItems(data);
Scene scene = new Scene(table);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch();
}
/**
* A cell that contains a text field that is always shown. The text of the
* text field is bound to the underlying data.
*/
public static class AlwaysEditingCell extends TableCell<ObservableList<StringProperty>, String> {
private final TextField textField;
public AlwaysEditingCell(int columnIndex) {
textField = new TextField();
this.emptyProperty().addListener((obs, wasEmpty, isNowEmpty) -> {
if (isNowEmpty) {
setGraphic(null);
} else {
setGraphic(textField);
}
});
// The index is not changed until tableData is instantiated, so this
// ensure the we wont get a NullPointerException when we do the
// binding.
this.indexProperty().addListener((obs, oldValue, newValue) -> {
ObservableList<ObservableList<StringProperty>> tableData = getTableView().getItems();
int oldIndex = oldValue.intValue();
if (oldIndex >= 0 && oldIndex < tableData.size()) {
textField.textProperty().unbindBidirectional(tableData.get(oldIndex).get(columnIndex));
}
int newIndex = newValue.intValue();
if (newIndex >= 0 && newIndex < tableData.size()) {
textField.textProperty().bindBidirectional(tableData.get(newIndex).get(columnIndex));
setGraphic(textField);
} else {
setGraphic(null);
}
});
}
}
/**
* A cell containing a checkbox. The checkbox represent the underlying value
* in the cell. If the cell value is 0, the checkbox is unchecked. Checking
* or unchecking the checkbox will change the underlying value.
*/
public static class CheckBoxCell extends TableCell<ObservableList<StringProperty>, String> {
private final CheckBox box;
private ObservableList<ObservableList<StringProperty>> tableData;
public CheckBoxCell(int columnIndex) {
this.box = new CheckBox();
this.emptyProperty().addListener((obs, wasEmpty, isNowEmpty) -> {
if (isNowEmpty) {
setGraphic(null);
} else {
setGraphic(box);
}
});
this.indexProperty().addListener((obs, oldValue, newValue) -> {
tableData = getTableView().getItems();
int newIndex = newValue.intValue();
if (newIndex >= 0 && newIndex < tableData.size()) {
// If active value is "1", the check box will be set to
// selected.
box.setSelected(tableData.get(getIndex()).get(columnIndex).equals("1"));
// We add a listener to the selected property. This will
// allow us to execute code every time the check box is
// selected or deselected.
box.selectedProperty().addListener((observable, oldVal, newVal) -> {
if (newVal) {
// If newValue is true the checkBox is selected, and
// we set the corresponding cell value to "1".
tableData.get(getIndex()).get(columnIndex).set("1");
} else {
// Otherwise we set it to "0".
tableData.get(getIndex()).get(columnIndex).set("0");
}
});
setGraphic(box);
} else {
setGraphic(null);
}
});
}
}
}
當按下TAB而聚焦TextField一個TableCell內部，焦點被正確地移動到下一個控制。但是，如果一個CheckBox一個TableCell內聚焦，焦點移動到TableView，而不是第一Control下一個Control。 SHIFT + TAB同時注重一個CheckBox將焦點移動到TableView最後的控制。如果我在TableView之外添加TextField，那麼在對齊CheckBox時，SHIFT + TAB實際上將會集中該TextField，而TAB行爲仍然至少將焦點保持在TableView之內。 CheckBox以某種方式打破了遍歷順序。
這是因爲TextField和CheckBox奇怪，我似乎有相同的TAB功能實現的，由於遍歷順序是第一個例子是正確的。我猜的是繼承Control類。
有誰知道這事？我試圖尋找某種EventFilter或聽衆的TAB和SHIFT + TAB命令Control，TextField，CheckBox，TextInputControl乃至Scene源裏面的源代碼，但我不能在任何地方找到它。
我也試過爲CheckBox單元實施我自己的TAB功能，最終導致另一個issue。