diff --git a/src/universal-dapp.js b/src/universal-dapp.js
index 299f832a94..0c95698aab 100644
--- a/src/universal-dapp.js
+++ b/src/universal-dapp.js
@@ -549,14 +549,15 @@ UniversalDApp.prototype.getCallButton = function (args) {
var decoded
self.runTx({ to: args.address, data: data, useCall: args.abi.constant && !isConstructor }, function (err, txResult) {
- var result
+ if (!txResult) {
+ replaceOutput($result, $('').text('callback contain no result ' + err).addClass('error'))
+ return
+ }
+ var result = txResult.result
if (err) {
replaceOutput($result, $('').text(err).addClass('error'))
// VM only
- } else {
- result = txResult.result
- }
- if (self.executionContext.isVM() && result.vm.exception === 0 && result.vm.exceptionError) {
+ } else if (self.executionContext.isVM() && result.vm.exception === 0 && result.vm.exceptionError) {
replaceOutput($result, $('').text('VM Exception: ' + result.vm.exceptionError).addClass('error'))
$result.append(getDebugTransaction(txResult))
// VM only