Webkit GTK :: How to detect when a download has fi

2020-02-12 14:52发布

问题:

I was wondering if there is a way to know when a webkitdownload has finished without error. I am using the C API. I was hoping a signal would be emitted (similar to when a download starts), however this seems to be not the case.

Searching the webkit API index, i see no signal which could be relevent: http://webkitgtk.org/reference/index-all.html

Must I really poll each webkit download until it has finished?

Cheers

回答1:

There's a signal that gets emitted when a download is complete. The signal is WebKitWebView "load-finished", you can also monitor the property changes of "load-status" still in the object WebKitWebView.

The following C code shows you how to:

  #include <gtk/gtk.h>
  #include <webkit/webkit.h>

  static void destroy_cb(GtkWidget* widget, gpointer data) {
    gtk_main_quit();
  }

  static void load_finished_cb(WebKitWebView *web_view, WebKitWebFrame *web_frame, gpointer data) {
      printf("Finished downloading %s\n", webkit_web_view_get_uri(web_view));
  }

  static void load_status_cb(GObject* object, GParamSpec* pspec, gpointer data) {
      WebKitWebView *web_view;
      WebKitLoadStatus status;
      const gchar *uri;

      web_view = WEBKIT_WEB_VIEW(object);
      status = webkit_web_view_get_load_status(web_view);
      uri = webkit_web_view_get_uri(web_view);

      switch (status) {
      case WEBKIT_LOAD_PROVISIONAL:
          printf("Load provisional: %s\n", uri);
          break;
      case WEBKIT_LOAD_COMMITTED:
          printf("Load commited: %s\n", uri);
          break;
      case WEBKIT_LOAD_FIRST_VISUALLY_NON_EMPTY_LAYOUT:
          printf("Load first visually non empty layout: %s\n", uri);
          break;
      case WEBKIT_LOAD_FINISHED:
          printf("Load finished: %s\n", uri);
          break;
      default:
          g_assert_not_reached();
      }
  }

  int main(int argc, char* argv[]) {
    const char *uri;
    GtkWidget* window;
    WebKitWebView* web_view;

    gtk_init(&argc, &argv);

    if (argc == 1) {
        printf("Usage: URI\n");
        return 1;
    }
    uri = argv[1];

    if(!g_thread_supported())
      g_thread_init(NULL);

    window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    gtk_window_set_default_size(GTK_WINDOW(window), 600, 400);
    g_signal_connect(window, "destroy", G_CALLBACK(destroy_cb), NULL);

    web_view = web_view = WEBKIT_WEB_VIEW(webkit_web_view_new());
    webkit_web_view_set_transparent(web_view, TRUE);

    /* Register a callback that gets invoked each time that a page is finished downloading */
    g_signal_connect(web_view, "load-finished", G_CALLBACK(load_finished_cb), NULL);

    /* Register a callback that gets invoked each time that the load status changes */
    g_object_connect(web_view, "signal::notify::load-status", G_CALLBACK(load_status_cb), NULL);

    webkit_web_view_load_uri(web_view, uri);

    gtk_container_add(GTK_CONTAINER(window), GTK_WIDGET(web_view));
    gtk_widget_grab_focus(GTK_WIDGET(web_view));
    gtk_widget_show_all(window);
    gtk_main();
    return 0;
  }


回答2:

You can use the 'download-requested' WebView signal to get a WebKitDownload. Then use a 'notify' WebKitDownload signal the same way you do with your WebView 's load status change.

I ran into this in Python, so I'll start with that in case I mistranslated below.

def on_download_requested(webview, download):
    #set the destination uri (downloads folder, etc)
    ...
    #connect the status change handler
    download.connect('notify::status', on_download_status_change)
    return True

def on_download_status_change(download, status):
    #get the status from download, since the provided status is a little weird
    #(i think this is specific to the binding)
    if download.get_status().value_name == 'WEBKIT_DOWNLOAD_STATUS_ERROR':
        #error handling
        ...
    elif download.get_status().value_name == 'WEBKIT_DOWNLOAD_STATUS_FINISHED':
        #the download is finished!
        ...
    else:
        ...

Or, modifying @potyl's answer for a C version... it seems pretty straightforward.

#include <gtk/gtk.h>
#include <webkit/webkit.h>


static void destroy_cb(GtkWidget* widget, gpointer data) {
  gtk_main_quit();
}

static void download_status_cb(GObject* object, GParamSpec* pspec, gpointer data){ //WebKitDownload *download, GObject* object, GParamSpec* pspec, gpointer data) {
    WebKitDownload *download;
    WebKitDownloadStatus status;
    concst gchar *uri;

    download = WEBKIT_DOWNLOAD(object);
    status = webkit_download_get_status(download);
    uri = webkit_download_get_uri(download):

    switch (status) {
      case WEBKIT_DOWNLOAD_STATUS_ERROR:
          printf("download error: %s\n", uri);
          break;
      case WEBKIT_DOWNLOAD_STATUS_CREATED:
          printf("download created: %s\n", uri);
          break;
      case WEBKIT_DOWNLOAD_STATUS_STARTED:
          printf("download started: %s\n", uri);
          break;
      case WEBKIT_DOWNLOAD_STATUS_CANCELLED:
          printf("download cancelled: %s\n", uri);
          break;
      case WEBKIT_DOWNLOAD_STATUS_FINISHED:
          printf("download finished!: %s\n", uri);
          break;
      default:
          g_assert_not_reached();
    }
}

static void download_requested_cb(WebKitWebView *web_view, WebKitDownload *download) {
  const char *filename;
  //note that if the suggested filename has spaces, it'll cause trouble below
  filename = webkit_download_get_suggested_filename();
  //set the destination uri (eg, send the file to a downloads folder)
  webkit_download_set_destination_uri(download,"file:///some/place/for/your/Downloads/test.mp3");
  //connect the status callback
  g_object_connect(download, "signal::notify::status", G_CALLBACK(download_status_cb), NULL);
  return true; //if we return false, the download will be cancelled
}

int main(int argc, char* argv[]) {
  const char *uri;
  GtkWidget* window;
  WebKitWebView* web_view;

  gtk_init(&argc, &argv);

  if (argc == 1) {
      printf("Usage: URI\n");
      return 1;
  }
  uri = argv[1];

  if(!g_thread_supported())
    g_thread_init(NULL);

  window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_window_set_default_size(GTK_WINDOW(window), 600, 400);
  g_signal_connect(window, "destroy", G_CALLBACK(destroy_cb), NULL);

  web_view = web_view = WEBKIT_WEB_VIEW(webkit_web_view_new());
  webkit_web_view_set_transparent(web_view, TRUE);

  /* Register a callback that gets invoked each time that a page is finished downloading */
  g_signal_connect(web_view, "load-finished", G_CALLBACK(load_finished_cb), NULL);

  /* Register a callback that gets invoked each time a download is requested */
  g_object_connect(web_view, "download-requested", G_CALLBACK(download_requested_cb), NULL);

  webkit_web_view_load_uri(web_view, uri);

  gtk_container_add(GTK_CONTAINER(window), GTK_WIDGET(web_view));
  gtk_widget_grab_focus(GTK_WIDGET(web_view));
  gtk_widget_show_all(window);
  gtk_main();
  return 0;
}

Hope the ugly, untested C translation helps :)



回答3:

Looks like you have to poll the WebKitDownload by hand:

WebKitDownloadStatus s = webkit_download_get_status(downloader);
if(s == WEBKIT_DOWNLOAD_STATUS_FINISHED) {
    /* The download has successfully finished. */
}
else if(s == WEBKIT_DOWNLOAD_STATUS_STARTED) {
    /* Still going, 100*webkit_download_get_progress(downloader) percent complete. */
}


标签: c webkit