WebView.callAsyncJavascriptFunction

Asynchronously call body with arguments in the script world with name world_name of the main frame current context in web_view. The arguments values must be one of the following types, or contain only the following GVariant types: number, string and dictionary. The result of the operation can be a Promise that will be properly passed to the callback. If world_name is null, the default world is used. Any value that is not null is a distin ct world. The source_uri will be shown in exceptions and doesn't affect the behavior of the script. When not provided, the document URL is used.

Note that if #WebKitSettings:enable-javascript is false, this method will do nothing. If you want to use this method but still prevent web content from executing its own JavaScript, then use #WebKitSettings:enable-javascript-markup.

When the operation is finished, callback will be called. You can then call webkit.web_view.WebView.callAsyncJavascriptFunctionFinish to get the result of the operation.

This is an example that shows how to pass arguments to a JS function that returns a Promise that resolves with the passed argument:

static void
web_view_javascript_finished (GObject      *object,
                              GAsyncResult *result,
                              gpointer      user_data)
{
    JSCValue               *value;
    GError                 *error = NULL;

    value = webkit_web_view_call_async_javascript_function_finish (WEBKIT_WEB_VIEW (object), result, &error);
    if (!value) {
        g_warning ("Error running javascript: %s", error->message);
        g_error_free (error);
        return;
    }

    if (jsc_value_is_number (value)) {
        gint32        int_value = jsc_value_to_string (value);
        JSCException *exception = jsc_context_get_exception (jsc_value_get_context (value));
        if (exception)
            g_warning ("Error running javascript: %s", jsc_exception_get_message (exception));
        else
            g_print ("Script result: %d\n", int_value);
        g_free (str_value);
    } else {
        g_warning ("Error running javascript: unexpected return value");
    }
    g_object_unref (value);
}

static void
web_view_evaluate_promise (WebKitWebView *web_view)
{
    GVariantDict dict;
    g_variant_dict_init (&dict, NULL);
    g_variant_dict_insert (&dict, "count", "u", 42);
    GVariant *args = g_variant_dict_end (&dict);
    const gchar *body = "return new Promise((resolve) => { resolve(count); });";
    webkit_web_view_call_async_javascript_function (web_view, body, -1, arguments, NULL, NULL, NULL, web_view_javascript_finished, NULL);
}
class WebView
void
callAsyncJavascriptFunction

Parameters

body_ string

the function body

length ptrdiff_t

length of body, or -1 if body is a nul-terminated string

arguments glib.variant.Variant

a #GVariant with format a{sv} storing the function arguments, or null

worldName string

the name of a #WebKitScriptWorld or null to use the default

sourceUri string

the source URI

cancellable gio.cancellable.Cancellable

a #GCancellable or null to ignore

callback gio.types.AsyncReadyCallback

a #GAsyncReadyCallback to call when the script finished