Udapp: show fallback button only if its in the ABI

src/universal-dapp.js

@@ -316,6 +316,8 @@ UniversalDApp.prototype.getInstanceInterface = function (contract, address, $tar
     $instance.append($title)
 
     // Add the fallback function
+    var fallback = self.getFallbackInterface(abi)
+    if (fallback) {
       $instance.append(self.getCallButton({
         abi: { constant: false, inputs: [], name: '(fallback)', outputs: [], type: 'function' },
         encode: function (args) {
@@ -323,6 +325,7 @@ UniversalDApp.prototype.getInstanceInterface = function (contract, address, $tar
         },
         address: address
       }))
+    }
 
     $.each(abi, function (i, funABI) {
       if (funABI.type !== 'function') {
@@ -379,6 +382,14 @@ UniversalDApp.prototype.getConstructorInterface = function (abi) {
   }
 }
 
+UniversalDApp.prototype.getFallbackInterface = function (abi) {
+  for (var i = 0; i < abi.length; i++) {
+    if (abi[i].type === 'fallback') {
+      return abi[i]
+    }
+  }
+}
+
 UniversalDApp.prototype.getCallButton = function (args) {
   var self = this
   // args.abi, args.encode, args.bytecode [constr only], args.address [fun only]