android, php, parsing JSON in php file sent from android

android, php, parsing JSON in php file sent from android

i have this JSON
{
"count":"3",
"num":"1",
"array":[
{
"id":"a_a",
"amount":56,
"duration":"0:12",
"time":1234566,
"type":0
},
{
"id":"a_a",
"amount":56,
"duration":"0:12",
"time":1234566,
"type":1
}
]
}
created it in android and send it by **HttpPost**
, i've tried a lot of ways to get the data in the php, my php file is this:
<?php
$response = array();
//$json_data = json_encode(stripslashes($_POST['jsonarray']))
$josn = file_get_contents("php://input");
$json_data = json_decode($josn,true);
$count = $json_data->{'count'};
$num = $json_data["num"];
$response["data"]=$count;
$response["data2"]=$num;
// echoing JSON response
echo json_encode($response);
?>
but $count and $num always returns null, any help please, and thanks.