JavaFX中的自动完成组合框

Question

我正在寻找一种将自动完成功能添加到JavaFX的方法ComboBox。经过大量搜索之后，该在这里提问了。

这AutoFillBox是已知的，但不是我要搜索的内容。我想要的是一个可编辑的组合框，键入时应过滤列表。但是我也想打开列表而不输入并查看整个项目。

任何的想法？

Answer 1

首先，您必须在项目中创建此类：import javafx.collections.FXCollections;import javafx.collections.ObservableList;import javafx.event.EventHandler;import javafx.scene.control.ComboBox;import javafx.scene.input.KeyCode;import javafx.scene.input.KeyEvent;public class FxUtilTest {&nbsp; &nbsp; public interface AutoCompleteComparator<T> {&nbsp; &nbsp; &nbsp; &nbsp; boolean matches(String typedText, T objectToCompare);&nbsp; &nbsp; }&nbsp; &nbsp; public static<T> void autoCompleteComboBoxPlus(ComboBox<T> comboBox, AutoCompleteComparator<T> comparatorMethod) {&nbsp; &nbsp; &nbsp; &nbsp; ObservableList<T> data = comboBox.getItems();&nbsp; &nbsp; &nbsp; &nbsp; comboBox.setEditable(true);&nbsp; &nbsp; &nbsp; &nbsp; comboBox.getEditor().focusedProperty().addListener(observable -> {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getSelectionModel().getSelectedIndex() < 0) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.getEditor().setText(null);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; });&nbsp; &nbsp; &nbsp; &nbsp; comboBox.addEventHandler(KeyEvent.KEY_PRESSED, t -> comboBox.hide());&nbsp; &nbsp; &nbsp; &nbsp; comboBox.addEventHandler(KeyEvent.KEY_RELEASED, new EventHandler<KeyEvent>() {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; private boolean moveCaretToPos = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; private int caretPos;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; @Override&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; public void handle(KeyEvent event) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (event.getCode() == KeyCode.UP) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; caretPos = -1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getEditor().getText() != null) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; moveCaret(comboBox.getEditor().getText().length());&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } else if (event.getCode() == KeyCode.DOWN) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (!comboBox.isShowing()) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.show();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; caretPos = -1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getEditor().getText() != null) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; moveCaret(comboBox.getEditor().getText().length());&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } else if (event.getCode() == KeyCode.BACK_SPACE) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getEditor().getText() != null) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; moveCaretToPos = true;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; caretPos = comboBox.getEditor().getCaretPosition();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } else if (event.getCode() == KeyCode.DELETE) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getEditor().getText() != null) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; moveCaretToPos = true;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; caretPos = comboBox.getEditor().getCaretPosition();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } else if (event.getCode() == KeyCode.ENTER) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (event.getCode() == KeyCode.RIGHT || event.getCode() == KeyCode.LEFT || event.getCode().equals(KeyCode.SHIFT) || event.getCode().equals(KeyCode.CONTROL)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; || event.isControlDown() || event.getCode() == KeyCode.HOME&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; || event.getCode() == KeyCode.END || event.getCode() == KeyCode.TAB) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; ObservableList<T> list = FXCollections.observableArrayList();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; for (T aData : data) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (aData != null && comboBox.getEditor().getText() != null && comparatorMethod.matches(comboBox.getEditor().getText(), aData)) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; list.add(aData);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; String t = "";&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getEditor().getText() != null) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; t = comboBox.getEditor().getText();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.setItems(list);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.getEditor().setText(t);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (!moveCaretToPos) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; caretPos = -1;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; moveCaret(t.length());&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (!list.isEmpty()) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.show();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; private void moveCaret(int textLength) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (caretPos == -1) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.getEditor().positionCaret(textLength);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; } else {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; comboBox.getEditor().positionCaret(caretPos);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; moveCaretToPos = false;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; });&nbsp; &nbsp; }&nbsp; &nbsp; public static<T> T getComboBoxValue(ComboBox<T> comboBox){&nbsp; &nbsp; &nbsp; &nbsp; if (comboBox.getSelectionModel().getSelectedIndex() < 0) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return null;&nbsp; &nbsp; &nbsp; &nbsp; } else {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return comboBox.getItems().get(comboBox.getSelectionModel().getSelectedIndex());&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }}要使组合框自动完成，请按以下方式使用它：FxUtilTest.autoCompleteComboBoxPlus(myComboBox, (typedText, itemToCompare) -> itemToCompare.getName().toLowerCase().contains(typedText.toLowerCase()) || itemToCompare.getAge().toString().equals(typedText));当需要从组合框中获取选定的值时，也请务必使用此方法，否则您可能会遇到一些异常，例如“类强制转换异常”：FxUtilTest.getComboBoxValue(myComboBox);PS：在jre 8.51和8.65之间的版本中，此方法存在一些问题，这导致了一些奇怪的行为，现在这些问题似乎不再发生了。如果您遇到问题，则可以查看对此答案所做的修改，并获得可以解决该问题的旧版本。此方法必须可以正常工作，如果您遇到任何问题，请告诉我。