个人中心
gpt4 book ai didi

java - 如何创建 JavaFx 应用程序实例并推送自己的参数？

转载 作者：行者123 更新时间：2023-12-02 12:09:38 26 4
gpt4 key购买 nike

我正在尝试使用 Google Maps Api + JavaFx 创建 map 。在主类中，我读取 JSON 文件，然后创建集群，程序的要点是将这些集群显示为标记，其中包含位置数量。因此，在主类中，我读取 JSON 文件，然后创建 DBSCANClusterer clusterer = new DBSCANClusterer(coordinates, 2, 2); 并且我必须将其推送到类 GoogleMap 中，其中JavaFX正在创建webView等等。我还用它在我的 html 文件中的脚本中使用 java 代码:

JSObject jsobj = (JSObject) webView.getEngine()
             .executeScript("window");
     jsobj.setMember("BrowserJavaObject", new BrowserJavaObject(clusterer));

然后，必须在所有聚类计算所在的 BrowserJavaObject 类中进一步推进相同的操作。我尝试创建 GoogleMap 类的对象，但这不起作用。那么如何让它发挥作用呢？或者说这有可能吗？谢谢您的建议。

JSONMain类:

public class JsonMain {

     static List<Coordinate> coordinates = new ArrayList<>();

    private static final String ITEMS_NAME = "items";
    private static final String LATITUDE_PROPERTY = "latitude";
    private static final String LONGITUDE_PROPERTY = "longitude";
    private static final String CRASH_NAME = "em_type_name";

    static void parseCrashCoordinates(final JsonReader jsonReader, final ICoordinatesListener listener)
            throws IOException {    
        // Reading JSON file
    }

     // Collecting all coordinates in ArrayList.
    private static void testCollecting()
            throws IOException {
      //  List<Coordinate> coordinates = new ArrayList<>();
        readAndParse((lat, lng) -> coordinates.add(new Coordinate(lat, lng)));
        System.out.println(coordinates.size());   
    }

    public static void main(String[] args) throws IOException, URISyntaxException {
        testCollecting();  


     // Initialize our clustering class with locations, minimum points in cluster and max Distance
        DBSCANClusterer clusterer = new DBSCANClusterer(coordinates, 2, 2);

        GoogleMap gm = new GoogleMap(clusterer);
        gm.launch(GoogleMap.class);
    }

GoogleMap 类:

public class GoogleMap extends Application {

private DBSCANClusterer clusterer ;

public GoogleMap(DBSCANClusterer c) {
    this.clusterer = c;
}


@Override 
public void start(Stage stage) throws MalformedURLException {

    File file = new File("C:/Users/Evgeny/git/Diploma_MSU/diploma/html/map.html");
    URL url222 = file.toURI().toURL();

     WebView webView = new WebView();
     final WebEngine webEngine = webView.getEngine();

     JSObject jsobj = (JSObject) webView.getEngine()
             .executeScript("window");
     jsobj.setMember("BrowserJavaObject", new BrowserJavaObject(clusterer));

    webEngine.load(url222.toString()); 

    // create scene
    stage.setTitle("Web Map");
    Scene scene = new Scene(webView,1000,700, Color.web("#666970"));
    stage.setScene(scene);
    // show stage
    stage.show();

} 
}

BrowserJavaObject 类:

public class BrowserJavaObject {

private DBSCANClusterer clusterer ;

public BrowserJavaObject(DBSCANClusterer c) {
    this.clusterer = c;
}

public String showMarkers() {
    ArrayList<ArrayList<Coordinate>> clusters_raw= this.clusterer.performClustering();
    ArrayList<Cluster> clusters = new ArrayList<>();

    String pointsArray = " [ ";
    for(int i=0; i<clusters_raw.size(); i++) {
            Cluster c = new Cluster(clusters_raw.get(i));
            clusters.add(c);

            pointsArray += c.getLocationAsArray() + " , ";
    }
    pointsArray += "]";

    System.out.println("Number Of Clusters Created: "+clusters.size());
    return pointsArray;

}
}

ma​​p.html:

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Map</title>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
    <style type="text/css">
        html { height: 100% }
        body { height: 100%; margin: 0; padding: 0 }
        #map_canvas { height: 100% }
    </style>
    <script async defer type="text/javascript"
            src="https://maps.googleapis.com/maps/api/js?callback=loadmap">
    </script>
</head>
<body onload="loadmap()">
<div id="map_canvas" style="width:100%; height:100%"></div>
<script>
var map;
function loadmap(){

  var options = {
      zoom: 16,
      center: new google.maps.LatLng(55.7558, 37.6173),
      mapTypeId: google.maps.MapTypeId.ROADMAP
  }
  map = new google.maps.Map(document.getElementById("map_canvas"), options);

  var markers = [];

  // Call the Java code to calculate clusters data, and save the returned clusters into a variable
  var markers_data = BrowserJavaObject.showMarkers();

  for( var i=0; i<markers_data.length; i++ ){
    var position = markers_data[i];
    var icon = "data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%2238%22%20height%3D%2238%22%20viewBox%3D%220%200%2038%2038%22%3E%3Cpath%20fill%3D%22%23a22%22%20stroke%3D%22%23ccc%22%20stroke-width%3D%22.5%22%20d%3D%22M34.305%2016.234c0%208.83-15.148%2019.158-15.148%2019.158S3.507%2025.065%203.507%2016.1c0-8.505%206.894-14.304%2015.4-14.304%208.504%200%2015.398%205.933%2015.398%2014.438z%22%2F%3E%3Ctext%20transform%3D%22translate%2819%2018.5%29%22%20fill%3D%22%23fff%22%20style%3D%22font-family%3A%20Arial%2C%20sans-serif%3Bfont-weight%3Abold%3Btext-align%3Acenter%3B%22%20font-size%3D%2212%22%20text-anchor%3D%22middle%22%3E" 
                + position[2]
              + "%3C%2Ftext%3E%3C%2Fsvg%3E";

//    if(zoom > 11) icon = null; //Default to marker with no number if at city zom level

    markers.push( new google.maps.Marker({
                    position: new google.maps.LatLng( position[0], position[1] ),
                    map: map,
                    title: position[2],
                    text: position[2],
                    icon: icon
                }) 
    );
  } 
}
</script>
</body>
</html>

因此 map 已加载，但那里没有集群。最终，所有这些聚类方法都不会被调用，因为我的 clusterer 对象没有在其他类中进一步传递。

非常感谢!

最佳答案

您使用 Application 类的方式是错误的。 Application 类代表您的整个应用程序并负责其生命周期；特别是，它有一个 start() 方法，当通过调用 launch() 启动 JavaFX 工具包时，会为您调用该方法。 Application 类并不代表 UI 的特定部分(这正是您的 GoogleMap 类的用途)。

因此，您应该使 JsonMain 成为 Application 的子类，而不是 GoogleMap，并且您应该将启动代码移至(恰当命名的) start() 方法:

public class GoogleMap {

    private DBSCANClusterer clusterer ;

    private final WebView view ;

    public GoogleMap(DBSCANClusterer c) throws MalformedURLException {
        this.clusterer = c;

        File file = new File("C:/Users/Evgeny/git/Diploma_MSU/diploma/html/map.html");
        URL url222 = file.toURI().toURL();

        view = new WebView();
        final WebEngine webEngine = webView.getEngine();

        JSObject jsobj = (JSObject) webView.getEngine()
                 .executeScript("window");
        jsobj.setMember("BrowserJavaObject", new BrowserJavaObject(clusterer));

        webEngine.load(url222.toString()); 

    } 

    public Node getView() {
        return view ;
    }

}

和

public class JsonMain extends Application {

    static List<Coordinate> coordinates = new ArrayList<>();

    private static final String ITEMS_NAME = "items";
    private static final String LATITUDE_PROPERTY = "latitude";
    private static final String LONGITUDE_PROPERTY = "longitude";
    private static final String CRASH_NAME = "em_type_name";

    static void parseCrashCoordinates(final JsonReader jsonReader, final ICoordinatesListener listener)
            throws IOException {    
        // Reading JSON file
    }

     // Collecting all coordinates in ArrayList.
    private static void testCollecting()
            throws IOException {
      //  List<Coordinate> coordinates = new ArrayList<>();
        readAndParse((lat, lng) -> coordinates.add(new Coordinate(lat, lng)));
        System.out.println(coordinates.size());   
    }

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

    @Override
    public void start(Stage stage)  
        throws IOException, URISyntaxException, MalformedURLException {

        testCollecting();  


     // Initialize our clustering class with locations, minimum points in cluster and max Distance
        DBSCANClusterer clusterer = new DBSCANClusterer(coordinates, 2, 2);

        GoogleMap gm = new GoogleMap(clusterer);

        // create scene
        stage.setTitle("Web Map");
        Scene scene = new Scene(gm.getView(), 1000, 700, Color.web("#666970"));
        stage.setScene(scene);
        // show stage
        stage.show();

    }

}

您可能应该进一步重构，以便正确分离您的关注点；例如解析数据等可能不是您的 Application 类的工作。但这至少可以让您将参数传递给您的 GoogleMap 类并让您启动应用程序以预期的方式。

关于java - 如何创建 JavaFx 应用程序实例并推送自己的参数？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46633632/

26 4 0
文章推荐： java - 对文件存在的不同行为进行单元测试
文章推荐： java - 显示 BufferedImage 后如何对其进行编辑？
文章推荐： java - Retrofit2 HTTP 获取 Json 到 RecyclerView
文章推荐： java - 如何用REGEX解析这种类型的字符串？
行者123
个人简介

我是一名优秀的程序员,十分优秀！

滴滴打车优惠券免费领取
滴滴打车优惠券
全站热门文章
Copyright 2021 - 2024 cfsdn All Rights Reserved 蜀ICP备2022000587号
广告合作:1813099741@qq.com 6ren.com