diff --git a/static/onnx.js b/static/onnx.js
index 42a406b..3743d71 100644
--- a/static/onnx.js
+++ b/static/onnx.js
@@ -533,35 +533,86 @@ onnx.Graph = class {
         // var min_input = schema.max_input
         var max_custom_add_input_num = Math.min(schema.max_input, 5)  // set at most 5 custom_add inputs
         var max_custom_add_output_num = Math.min(schema.max_output, 5)  // set at most 5 custom_add outputs
-
+        
+        // console.log(node_info)
         var inputs = []
         for (let i = 0; i < schema.inputs.length; ++i) {
             const input = schema.inputs[i]
+            
+            var node_info_input = node_info.inputs.get(input.name)
+            console.log(node_info_input)
+
             var arg_list = []
             if (input.list) {
                 for (let j = 0; j < max_custom_add_input_num; ++j) {
-                    var arg_name = 'custom_input_' + (this.custom_add_node_io_idx++).toString()
+                    if (node_info_input && node_info_input[j]) {
+                        var arg_name = node_info_input[j]
+                    }
+                    else {
+                        var arg_name = 'custom_input_' + (this._custom_add_node_io_idx++).toString()
+                    }
                     arg_list.push(this._context.argument(arg_name))
                 }
             }
             else {
-                var arg_name = 'custom_input_' + (this.custom_add_node_io_idx++).toString()
+                // if (node_info_input) {
+                //     if (!node_info_input[0]) {
+                //         console.log('got empty')
+                //     }
+                //     else {
+                //         console.log(node_info_input[0])
+                //     } 
+                // }
+
+                if (node_info_input && node_info_input[0]) {
+                    var arg_name = node_info_input[0]
+                }
+                else {
+                    var arg_name = 'custom_input_' + (this._custom_add_node_io_idx++).toString()
+                }
                 arg_list = [this._context.argument(arg_name)]
             }
+
+            // var arg_list = []
+            // if (input.list) {
+            //     for (let j = 0; j < max_custom_add_input_num; ++j) {
+            //         var arg_name = 'custom_input_' + (this._custom_add_node_io_idx++).toString()
+            //         arg_list.push(this._context.argument(arg_name))
+            //     }
+            // }
+            // else {
+            //     var arg_name = 'custom_input_' + (this._custom_add_node_io_idx++).toString()
+            //     arg_list = [this._context.argument(arg_name)]
+            // }
+
             inputs.push(new onnx.Parameter(input.name, arg_list));
         }
+
         var outputs = []
         for (let i = 0; i < schema.outputs.length; ++i) {
             const output = schema.outputs[i]
+            var node_info_output = node_info.outputs.get(output.name)
+
             var arg_list = []
             if (output.list) {
                 for (let j = 0; j < max_custom_add_output_num; ++j) {
-                    var arg_name = 'custom_output_' + (this.custom_add_node_io_idx++).toString()
+                    if (node_info_output && node_info_output[j]) {
+                        var arg_name = node_info_output[j]
+                    }
+                    else {
+                        var arg_name = 'custom_output_' + (this._custom_add_node_io_idx++).toString()
+                    }
                     arg_list.push(this._context.argument(arg_name))
                 }
             }
             else {
-                var arg_name = 'custom_output_' + (this.custom_add_node_io_idx++).toString()
+                if (node_info_output && node_info_output[0]) {
+                    var arg_name = node_info_output[0]
+                }
+                else {
+                    var arg_name = 'custom_output_' + (this._custom_add_node_io_idx++).toString()
+                }
+                
                 arg_list = [this._context.argument(arg_name)]
             }
             outputs.push(new onnx.Parameter(output.name, arg_list));
diff --git a/static/view-sidebar.js b/static/view-sidebar.js
index eafb649..10ee072 100644
--- a/static/view-sidebar.js
+++ b/static/view-sidebar.js
@@ -682,7 +682,7 @@ class NodeAttributeView {
 
                 var attr_input = document.createElement("INPUT");
                 attr_input.setAttribute("type", "text");
-                attr_input.setAttribute("value", content ? content : '&nbsp;');
+                attr_input.setAttribute("value", content ? content : 'undefined');
                 attr_input.addEventListener('input', (e) => {
                     // console.log(e.target.value);
                     this._host._view._graph.changeNodeAttribute(this._modelNodeName, this._attributeName,  e.target.value);
@@ -860,7 +860,7 @@ sidebar.ArgumentView = class {
                 // console.log(this._argument)
                 // console.log(this._argument.name)
                 // console.log(e.target.value);
-                this._host._view._graph.changeNodeInput(this._modelNodeName, this._parameterName, this._arg_index, e.target.value);
+                this._host._view._graph.changeNodeInputOutput(this._modelNodeName, this._parameterName, this._arg_index, e.target.value);
                 // console.log(this._host._view._graph._renameMap);
             });
             this._element.appendChild(arg_input);
diff --git a/static/view.js b/static/view.js
index 5861ea0..8a4d57a 100644
--- a/static/view.js
+++ b/static/view.js
@@ -875,14 +875,24 @@ view.View = class {
             var node = this._graphs[0].make_custom_add_node(node_info)
             // console.log(node)
             
-            // padding empty array for LightNodeInfo.inputs/outputs
-            for (var input of node.inputs) {
-                var arg_len = input._arguments.length
-                this.lastViewGraph._addedNode.get(modelNodeName).inputs.set(input.name, new Array(arg_len))
+            // padding empty array for LightNodeInfo.inputs/outputs (only when initializing)
+            if (this.lastViewGraph._addedNode.get(modelNodeName).inputs.size == 0) {
+
+                for (var input of node.inputs) {
+                    var arg_len = input._arguments.length
+                    this.lastViewGraph._addedNode.get(modelNodeName).inputs.set(input.name, new Array(arg_len))
+                }
+            }
+
+            if (this.lastViewGraph._addedNode.get(modelNodeName).outputs.size == 0) {
+
+                for (var output of node.outputs) {
+                    var arg_len = output._arguments.length
+                    this.lastViewGraph._addedNode.get(modelNodeName).outputs.set(output.name, new Array(arg_len))
+                }
             }
 
         }
-        // console.log(this.view._graphs[0].nodes)
         // console.log(this.lastViewGraph._addedNode)
     }
 
@@ -1140,7 +1150,7 @@ view.Graph = class extends grapher.Graph {
         // console.log(properties)
         // this._addedNode.push(new view.LightNodeInfo(properties))
         this._addedNode.set(modelNodeName, new view.LightNodeInfo(properties))
-        console.log(this._addedNode)
+        // console.log(this._addedNode)
         
         // refresh
         // this.refresh_added_node()
@@ -1173,10 +1183,16 @@ view.Graph = class extends grapher.Graph {
         // console.log(this._addedNode)
     }
 
-    changeNodeInput(modelNodeName, parameterName, arg_index, targetValue) {
+
+    changeNodeInputOutput(modelNodeName, parameterName, arg_index, targetValue) {
         if (this._addedNode.has(modelNodeName)) {
-            this._addedNode.get(modelNodeName).inputs.get(parameterName)[arg_index] = targetValue
+            if (this._addedNode.get(modelNodeName).inputs.has(parameterName)) {
+                this._addedNode.get(modelNodeName).inputs.get(parameterName)[arg_index] = targetValue
+            }
 
+            if (this._addedNode.get(modelNodeName).outputs.has(parameterName)) {
+                this._addedNode.get(modelNodeName).outputs.get(parameterName)[arg_index] = targetValue
+            }
         }
         // console.log(this._addedNode)
     }
@@ -1407,7 +1423,7 @@ view.LightNodeInfo = class {
         this.properties = properties
         this.attributes = attributes || new Map()
         this.inputs = inputs || new Map()
-        this.outputs = outputs || []
+        this.outputs = outputs || new Map()
     }
 }