Javascript 界面与 android 不工作

Question

我正在尝试将变量从 Android 传递到 JavaScript。单击 map 按钮时，它将使用以下 onCreate 方法打开此类:

@SuppressLint("JavascriptInterface")
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.maps);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

    myWebView = (WebView) findViewById(R.id.webview);
    setMyWebviewSettings(myWebView.getSettings());

    myWebView.setWebViewClient(new WebViewClient());
    myWebView.setWebChromeClient(new WebChromeClient());

    Bundle extras = getIntent().getExtras();
    double[] coordinates = setCoordinates(extras);

    myWebView.addJavascriptInterface(new JavaScriptInterface(coordinates), "JSInterface");

    myWebView.loadUrl("http://10.0.0.32:8887/services/maps/examples/basic-example.htm");
}

这是setMyWebviewSettings方法:

private void setMyWebviewSettings(WebSettings MyWebviewSettings){
    MyWebviewSettings.setAllowFileAccessFromFileURLs(true);
    MyWebviewSettings.setAllowUniversalAccessFromFileURLs(true);
    MyWebviewSettings.setJavaScriptCanOpenWindowsAutomatically(true);
    MyWebviewSettings.setJavaScriptEnabled(true);
    MyWebviewSettings.setDomStorageEnabled(true);
    MyWebviewSettings.setJavaScriptCanOpenWindowsAutomatically(true);
    MyWebviewSettings.setBuiltInZoomControls(true);
    MyWebviewSettings.setAllowFileAccess(true);
    MyWebviewSettings.setSupportZoom(true);
}

然后这是JavaScriptInterface:

public class JavaScriptInterface {

    double lat;
    double lon;
    double pan;

    JavaScriptInterface(double[] coordinate) {
        this.lat = coordinate[0];
        this.lon = coordinate[1];
        this.pan = coordinate[2];
    }

    public double getLatValue() {
        return lat;
    }

    public double getLonValue() {
        return lon;
    }

    public double getPanValue() {
        return pan;
    }
}

这是setCooperatives方法:

private double[] setCoordinates(Bundle extras) {

    double[] coordinates = new double[3];

    coordinates[0] = 45.9049;
    coordinates[1] = 13.3177;
    coordinates[2] = 15;

    if (extras != null) {
        coordinates[0] = extras.getDouble("lat");
        coordinates[1] = extras.getDouble("lon");
        coordinates[2] = extras.getDouble("pan");
    }
    return coordinates;
}

一切正常，只是不加载 map 。 Bundle extras 为 Null。如何解决这个问题？

Answer 1

确保在创建启动第二个 Activity 的 Intent 时传递值。如果 bundle 为空，则意味着它们不包含在 Intent 中。