java - Wifi scanner with 20 scanning purpose -


i trying built array of class , putting values objects still showing null pointer exception.

my code :

class wifiscanreceiver extends broadcastreceiver {           @suppresslint("usevalueof")           public void onreceive(context c, intent intent) {                list<scanresult> wifilist = wifi.getscanresults();                  info = wifi.getconnectioninfo();                 int k = wifilist.size();                    scan_data[] data = new scan_data[k];               (int i=0;i<20;i++){                 wifi.startscan();                 list<scanresult> wifilist1 = wifi.getscanresults();                  int l = wifilist1.size();                  if (i==0){                 (int j=0;j<l;j++){                     data[j].ssid = wifilist1.get(j).ssid.tostring();                     data[j].bssid = wifilist1.get(j).bssid.tostring();                     data[j].lvl = wifilist1.get(j).level;                     data[j].count++;                 }

if tell me why showing null pointer exception @ 

data[j].ssid = wifilist1.get(j).ssid.tostring();

problem scan_data array not initialized objects.

scan_data[] data = new scan_data[k];

this initializing array not putting objects in it. have explicitly in loop. create scan_data object , put values in , put on data[j].

         (int j=0;j<l;j++){                 scan_data sdata = new scan_data();   //            set desired values in sdata scandata                 data[j] = sdata;             }

hope helps.


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