我想用这个来选择自定义组合框的值:演员串
import java.util.List;
import javafx.application.Application;
import static javafx.application.Application.launch;
import static javafx.application.Application.launch;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
import javafx.util.Callback;
import javafx.util.StringConverter;
public class MainApp extends Application
{
public static void main(String[] args)
{
launch(args);
}
@Override
public void start(Stage stage)
{
final ComboBox<ListGroupsObj> listGroups = new ComboBox();
listGroups.setButtonCell(new GroupListCell());
listGroups.setCellFactory(new Callback<ListView<ListGroupsObj>, ListCell<ListGroupsObj>>()
{
@Override
public ListCell<ListGroupsObj> call(ListView<ListGroupsObj> p)
{
return new GroupListCell();
}
});
listGroups.setEditable(true);
listGroups.setConverter..............
// Insert Some data
ListGroupsObj ob = ListGroupsObj.newInstance().groupId(12).groupName("Test");
listGroups.getItems().addAll(ob);
ListGroupsObj osb = ListGroupsObj.newInstance().groupId(13).groupName("Test2");
listGroups.getItems().addAll(osb);
listGroups.setValue(ob);
// Display the selected Group
listGroups.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<ListGroupsObj>()
{
@Override
public void changed(ObservableValue<? extends ListGroupsObj> arg0, ListGroupsObj arg1, ListGroupsObj arg2)
{
if (arg2 != null)
{
System.out.println("Selected Group: " + arg1.getGroupId() + " - " + arg2.getGroupName());
}
}
});
final StackPane layout = new StackPane();
layout.getChildren().add(listGroups);
layout.setStyle("-fx-background-color: cornsilk; -fx-padding: 15;");
stage.setScene(new Scene(layout));
stage.show();
}
class GroupListCell extends ListCell<ListGroupsObj>
{
@Override
protected void updateItem(ListGroupsObj item, boolean empty)
{
super.updateItem(item, empty);
if (item != null)
{
setText(item.getGroupId() + " - " + item.getGroupName());
}
}
}
private List<ListGroupsObj> listGroups;
public static class ListGroupsObj
{
private int groupId;
private String groupName;
public static ListGroupsObj newInstance()
{
return new ListGroupsObj();
}
public ListGroupsObj()
{
}
public ListGroupsObj groupId(int groupId)
{
this.groupId = groupId;
return this;
}
public ListGroupsObj groupName(String groupName)
{
this.groupName = groupName;
return this;
}
public int getGroupId()
{
return groupId;
}
public String getGroupName()
{
return groupName;
}
@Override
public String toString()
{
return groupId + " - " + groupName;
}
}
public class GroupConverter extends StringConverter<ListGroupsObj>
{
@Override
public String toString(ListGroupsObj obj)
{
return obj.getGroupId() + " - " + obj.getGroupName();
}
@Override
public ListGroupsObj fromString(String obj)
{
//TODO when you type for example "45 - NextGroup" you want to take only tyhe number"
return ListGroupsObj.newInstance().groupName(obj);
}
}
}
我得到这个错误,当我点击下拉框中之外:
Exception in thread "JavaFX Application Thread" java.lang.ClassCastException: java.lang.String cannot be cast to com.selectmenuexample.MainApp$ListGroupsObj
我发现这可以使用转换器完成,但我现在知道如何使用它。你能帮助这个实现吗?
'listGroups.setConverter ..............'看起来像你应该设置你的自定义字符串转换器在这一行。 – SimY4