我有一个ListView，上面有一个TextField。如果用户在文本字段中输入搜索查询，则列表视图将更新并过滤自身以显示相关结果。
ListView显示FilteredList中的项目，该项目填充了Employee对象。每个员工都有名字和姓氏。
package application.ctrl;
import java.io.IOException;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.collections.transformation.FilteredList;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.geometry.Pos;
import javafx.geometry.Side;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.CustomMenuItem;
import javafx.scene.control.ListView;
import javafx.scene.control.TextField;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import application.Main;
import application.objects.Employee;
import application.objects.EmployeeDatabase;
public class EmployeePickerWidget extends VBox implements Initializable {
@FXML
private TextField textField;
@FXML
private Button addNewEmployee;
@FXML
private ListView<Employee> employeeList;
private FilteredList<Employee> filteredList;
private ContextMenu cm;
private CustomMenuItem item;
private ClickedEmployeeInterface parent;
public EmployeePickerWidget(ClickedEmployeeInterface parent) {
FXMLLoader loader = new FXMLLoader(this.getClass().getResource(
Main.EMPLOYEE_PICKER));
loader.setRoot(this);
loader.setController(this);
try {
loader.load();
} catch (IOException e) {
e.printStackTrace();
}
this.parent = parent;
}
@Override
public void initialize(URL location, ResourceBundle resources) {
setupEmployeeListView();
setupTextField();
}
private void setupEmployeeListView() {
filteredList = new FilteredList<Employee>(EmployeeDatabase.getInstance()
.getObservableList());
employeeList = new ListView<Employee>();
employeeList.setItems(filteredList);
employeeList.setOnMouseClicked(arg0 -> {
if (employeeList.getSelectionModel().getSelectedItem() != null) {
cm.hide();
parent.handleClickedEmployee();
}
});
}
private void setupTextField() {
textField.textProperty().addListener(
(observable, oldValue, newValue) -> {
filteredList.setPredicate(employee -> {
return filterHelper(employee, newValue);
});
});
textField.setText(" ");
textField.setText("");
textField.setOnMouseClicked(event -> cm
.show(textField, Side.BOTTOM, 0, 0));
cm = new ContextMenu();
item = new CustomMenuItem();
VBox container = new VBox();
container.setAlignment(Pos.CENTER_RIGHT);
container.getChildren().add(employeeList);
Button defineEmployeeBtn = new Button("Define New Employee");
defineEmployeeBtn.setOnAction(event -> {
FXMLLoader loader = new FXMLLoader(getClass().getResource(
Main.DEFINE_NEW_EMPLOYEE));
Parent root = null;
try {
root = loader.load();
} catch (IOException e) {
e.printStackTrace();
}
Scene newScene = new Scene(root);
Stage newStage = new Stage();
newStage.setScene(newScene);
newStage.show();
});
container.getChildren().add(defineEmployeeBtn);
item.setContent(container);
cm.getItems().add(item);
}
private boolean filterHelper(Employee employee, String query) {
String first = employee.getFirst().toLowerCase(), last = employee
.getLast().toLowerCase();
String[] querySplit = query.replace(",", "\\s").split("\\s+");
int length = querySplit.length;
for (int i = 0; i < length; i++)
querySplit[i] = querySplit[i].toLowerCase();
if (length == 1) {
if (first.contains(querySplit[0]) || last.contains(querySplit[0]))
return true;
else
return false;
} else if (length == 2) {
if (first.contains(querySplit[0]) || last.contains(querySplit[0]))
if (first.contains(querySplit[1]) || last.contains(querySplit[1]))
return true;
return false;
} else if (length == 3) {
return false;
}
return false;
}
public Employee getEmployee() {
return employeeList.getSelectionModel().getSelectedItem();
}
@FXML
public void addNewEmployee() {
}
}
interface ClickedEmployeeInterface {
void handleClickedEmployee();
}
如果有3名员工被命名为＆＃34;唐纳德特朗普＆＃34;，＆＃34;唐纳德史密斯＆＃34;和＆＃34;唐纳德杰克逊＆＃34;在数据库中，需要进行以下操作：
问题是，在我进入空间后，ListView中断了，我的所有Employees都从ListView中消失了。当我在文本字段外单击并再次单击时，它会触发：
textField.setOnMouseClicked(event -> cm
.show(textField, Side.BOTTOM, 0, 0));
我的ListView突然再次起作用，显示出一个Employee。
如何正确制作ListView过滤器而无需单击并重新登录？
答案 0 :(得分：0)
我没有FXML文件，因此我无法复制您的问题。您的代码存在多个问题，这不是最佳解决方案，仍然，我已编辑您的答案，为您提供提示并帮助您了解可能出现逻辑错误的区域
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.Event;
import javafx.event.EventHandler;
import javafx.geometry.Side;
import javafx.scene.Scene;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.Label;
import javafx.scene.control.MenuItem;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;
public class DemoList extends Application {
@Override
public void start(Stage stage) throws Exception {
GridPane gridPane = new GridPane();
Label label = new Label("Name");
final TextField textField = new TextField();
textField.setFocusTraversable(false);
textField.setPromptText("Please Type Here");
final ContextMenu cm = new ContextMenu();
final ObservableList<String> employeeList = FXCollections
.observableArrayList();
employeeList.addAll("Donald Duck", "Donald Mouse", "Donald Goofy");
textField.textProperty().addListener(new ChangeListener<String>() {
@Override
public void changed(ObservableValue<? extends String> arg0,
String arg1, String arg2) {
// To clear the Context Menu so that same items are not added
// multiple times
cm.getItems().clear();
for (String employee : employeeList) {
if (filterHelper(employee, arg2)) {
cm.getItems().add(new MenuItem(employee));
}
}
}
});
textField.setOnMouseClicked(new EventHandler<Event>() {
@Override
public void handle(Event arg0) {
// To clear the Context Menu so that same items are not added
// multiple times
cm.getItems().clear();
//Adding the data for initial click
for (String employee : employeeList) {
if (filterHelper(employee, textField.getText())) {
cm.getItems().add(new MenuItem(employee));
}
}
cm.show(textField, Side.BOTTOM, 0, 0);
}
});
gridPane.add(label, 0, 0);
gridPane.add(textField, 0, 1);
Scene scene = new Scene(gridPane, 300, 300);
stage.setScene(scene);
stage.show();
}
private boolean filterHelper(String employee, String query) {
//Splitting Employee name to fetch first and last name
String first = employee.split(" ")[0].toLowerCase(), last = employee
.split(" ")[1].toLowerCase();
String[] querySplit = query.replace(",", "\\s").split("\\s+");
int length = querySplit.length;
for (int i = 0; i < length; i++)
querySplit[i] = querySplit[i].toLowerCase();
/**
* Avoid adding unnecessary return statement
* I have removed all the 'return false' statements
* The last return will take care of all the 'return false'
*/
//only single word
if (length == 1) {
if (first.startsWith(querySplit[0])
|| last.startsWith(querySplit[0]))
return true;
}
//two words, considering first word is first name
//and second word is last name
else if (length == 2) {
if (first.startsWith(querySplit[0])
&& last.startsWith(querySplit[1]))
return true;
}
return false;
}
public static void main(String[] args) {
launch(args);
}
}