Asynchronous HTTP requests in Android--fragment

1. Customizing asynchronous task

    /*** Asynchronous acquisition of real-time data*/     Public classTimerdatataskextendsAsynctask<void, Void, boolean>{@OverrideprotectedBoolean doinbackground (Void ... params) {String GetUrl= Murl + "/realtimedata.ashx?type=data"; URL loginurl=NULL; InputStream in=NULL; HttpURLConnection Conn=NULL; //Initialize listMdatalist =NewArraylist<datalistitem>(); Try{loginurl=NewURL (GETURL); Conn=(HttpURLConnection) loginurl.openconnection (); Conn.setrequestproperty ("Charset", "UTF-8"); if(Conn.getresponsecode () = = 200) { in=NewBufferedinputstream (Conn.getinputstream ()); Scanner Scanner=NewScanner (in). Usedelimiter ("\\a"); String result= Scanner.hasnext ()? Scanner.next (): ""; LOG.E (Mlogtimerdata,result);} conn.disconnect (); } Catch(IOException ex) {LOG.E (getString (R.string.log_e_url_error), ex.tostring ()); }Catch(Jsonexception ex) {LOG.E (getString (R.string.log_e_json_error), ex.tostring ()); }            return true; } @Overrideprotected voidOnPostExecute (FinalBoolean Success) {//Message msg = new Message ();//uihandler.sendmessage (msg);            if(Getactivity ()! =NULL) {getactivity (). Runonuithread (Uirefreshthread); } mtask=NULL; } @Overrideprotected voidoncancelled () {Mtask=NULL; }    }

2. Refresh the listview in the main thread

Runnable Uirefreshthread =NewRunnable () {@Override Public voidrun () {if(Getactivity ()! =NULL) {                //Initialize AdapterMadapter =NewDatalistadapter (Getactivity (), R.layout.fragment_data_list_item, mdatalist); //Set the adapterMlistview.setadapter (Madapter); Mswipelayout.setrefreshing (false); Mlistview.setenabled (true); }        }    };

    New Runnable () {        @Override        publicvoid  run () {            mlistview.setenabled ( false );        }    };

3. Scheduled Tasks

    New Timer ();     New TimerTask () {        @Override        publicvoid  run () {            if( Getactivity ()! =null) {                getactivity (). Runonuithread (Uithread)                ; New Timerdatatask ();                 NULL );            }        }    };

Each time the refresh is, re-new a adapter object, using Notifydatasetchanged (), there will be an irregular bug exception

Asynchronous HTTP requests in Android--fragment