I discovered. In conventional Webkit browsers, the place to download the console shows how the request canceled, so before turning to "download manager" of the browser the request should be canceled.

solution:

Qt Code: 
  1. //replace [QWebView] by your WebView
  2. connect([QWebView]->page(), SIGNAL(unsupportedContent(QNetworkReply*)),
  3. this, SLOT(downloadContent(QNetworkReply*)));
  4.  
  5. ...
  6.  
  7. void [main class]::downloadContent(QNetworkReply *reply){
  8.     //Replace "[main class]" by "Class" having the signs used in WebView.
  9.  
  10.     [QWebView]->stop();
  11.     //solution: stop loading --replace [QWebView] by your WebView
  12.  
  13.     /*function to donwload*/
  14. }
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http://stackoverflow.com/questions/1...82607#16782607