invokeTx.on('complete') is not executing

[ashish9308]

This line is not executing for me due to that I'm not able to invoke the query: I'm getting console.log for this : Successfully submitted chaincode invoke transaction then nothing please provide me any solution.
invokeTx.on('complete', function(results) {
// Invoke transaction completed successfully
console.log(util.format("\nSuccessfully completed chaincode invoke transaction: request=%j, response=%j", invokeRequest, results));
query();
});