fix dropdown panel

src/ui/DropdownPanel.js

@@ -82,13 +82,17 @@ DropdownPanel.prototype.toggle = function () {
 }
 
 DropdownPanel.prototype.hide = function () {
-  var el = this.view.querySelector('.dropdownpanel')
-  el.style.display = 'none'
+  if (this.view) {
+    var el = this.view.querySelector('.dropdownpanel')
+    el.style.display = 'none'
+  }
 }
 
 DropdownPanel.prototype.show = function () {
-  var el = this.view.querySelector('.dropdownpanel')
-  el.style.display = ''
+  if (this.view) {
+    var el = this.view.querySelector('.dropdownpanel')
+    el.style.display = ''
+  }
 }
 
 module.exports = DropdownPanel

src/ui/TxBrowser.js

@@ -40,7 +40,9 @@ TxBrowser.prototype.setDefaultValues = function () {
   this.basicPanel.update()
   this.basicPanel.hide()
   this.updateWeb3Url(util.web3.currentProvider.host)
-  yo.update(this.view, this.render())
+  if (this.view) {
+    yo.update(this.view, this.render())
+  }
 }
 
 TxBrowser.prototype.submit = function () {