From bf8e2b15bae1342e9c50a3ec0049284d934e1573 Mon Sep 17 00:00:00 2001
From: Jaco Greeff <jacogr@gmail.com>
Date: Wed, 27 Feb 2019 15:04:03 +0100
Subject: [PATCH] Check instanceof to determine param (numbers only) (#764)

---
 packages/ui-params/src/Param/findComponent.ts | 14 ++++++++++++--
 packages/ui-params/src/initValue.ts           | 11 +++++++++--
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/packages/ui-params/src/Param/findComponent.ts b/packages/ui-params/src/Param/findComponent.ts
index 5d7be0d928..7fc3f9ef4d 100644
--- a/packages/ui-params/src/Param/findComponent.ts
+++ b/packages/ui-params/src/Param/findComponent.ts
@@ -2,7 +2,7 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
-import { TypeDef, TypeDefInfo } from '@polkadot/types';
+import { TypeDef, TypeDefInfo, UInt, createType } from '@polkadot/types';
 import { Props, ComponentMap } from '../types';
 
 import Account from './Account';
@@ -72,5 +72,15 @@ export default function findComponent (def: TypeDef, overrides: ComponentMap = {
     }
   })(def);
 
-  return overrides[type] || components[type] || Unknown;
+  let Component = overrides[type] || components[type];
+
+  if (!Component) {
+    const instance = createType(type);
+
+    if (instance instanceof UInt) {
+      return Amount;
+    }
+  }
+
+  return Component || Unknown;
 }
diff --git a/packages/ui-params/src/initValue.ts b/packages/ui-params/src/initValue.ts
index 8e021b569f..7a79c6ebb5 100644
--- a/packages/ui-params/src/initValue.ts
+++ b/packages/ui-params/src/initValue.ts
@@ -5,7 +5,7 @@
 import { RawParam$Value } from './types';
 
 import BN from 'bn.js';
-import { Bytes, Hash, TypeDef, TypeDefInfo } from '@polkadot/types';
+import { Bytes, Hash, TypeDef, TypeDefInfo, UInt, createType } from '@polkadot/types';
 
 export default function getInitValue (def: TypeDef): RawParam$Value | Array<RawParam$Value> {
   if (def.info === TypeDefInfo.Vector) {
@@ -78,8 +78,15 @@ export default function getInitValue (def: TypeDef): RawParam$Value | Array<RawP
     case 'Signature':
       return void 0;
 
-    default:
+    default: {
+      const instance = createType(type);
+
+      if (instance instanceof UInt) {
+        return new BN(0);
+      }
+
       console.error(`Unable to determine default type for ${JSON.stringify(def)}`);
       return void 0;
+    }
   }
 }