UI控件-> ListView（2)

package	javafxui;

import javafx.application.Application;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.layout.Priority;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.scene.text.Font;
import javafx.stage.Stage;

public class LearnUI extends Application {

    ListView<String> list = new ListView<>();
    ObservableList<String> data = FXCollections.observableArrayList(
            "chocolate", "salmon", "gold", "coral", "darkorchid",
            "darkgoldenrod", "lightsalmon", "black", "rosybrown", "blue",
            "blueviolet", "brown");
    final Label label = new Label();

    @Override
    public void start(Stage stage) {
        VBox box = new VBox();
        Scene scene = new Scene(box, 200, 200);
        stage.setScene(scene);
        stage.setTitle("ListViewSample");
        box.getChildren().addAll(list, label);
        VBox.setVgrow(list, Priority.ALWAYS);//垂直适应窗口大小

        label.setLayoutX(10);
        label.setLayoutY(115);
        label.setFont(Font.font("Verdana", 20));

        list.setItems(data);

        list.setCellFactory((ListView<String> l) -> new ColorRectCell());

        //为选中的list Item 显示对应颜色的 文本
        list.getSelectionModel().selectedItemProperty().addListener(
                (ObservableValue<? extends String> ov, String old_val,
                        String new_val) -> {
                    label.setText(new_val);
                    label.setTextFill(Color.web(new_val));
                });
        	stage.show();
    }

    static class ColorRectCell extends ListCell<String> {

    	//item 就是指ListView  中的item 元素
        @Override
        public void updateItem(String item, boolean empty) {
        	super.updateItem(item, empty);
        	Rectangle rectangle = new Rectangle(100, 20);
        	if(item != null) {
        		rectangle.setFill(Color.web(item));
        		setGraphic(rectangle);
        	}
        	else {
        		setGraphic(null);
        	}
        }
    }

    public static void main(String[] args) {
        launch(args);
    }
}