location tree view

lib/pages/locations.dart

@@ -1,6 +1,7 @@
 import 'package:cdb_ui/api.dart';
 import 'package:cdb_ui/pages/transaction.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_simple_treeview/flutter_simple_treeview.dart';
 import 'package:qr_bar_code_scanner_dialog/qr_bar_code_scanner_dialog.dart';
 
 class LocationsPage extends StatefulWidget {
@@ -25,10 +26,29 @@ class _LocationsPageState extends State<LocationsPage> {
     );
   }
 
+  TreeNode buildTree(BuildContext context, String locID) {
+    return TreeNode(
+        key: ValueKey(locID),
+        content: ListTile(
+          title: Text(locations![locID]!.name),
+          onTap: () {
+            Navigator.of(context).push(MaterialPageRoute(
+              builder: (context) => LocationView(locations![locID]!),
+            ));
+          },
+        ),
+        children: locations!.keys.where((key2) {
+          if (locations![key2]!.parent != null) {
+            return locations![key2]!.parent! == locations![locID]!.id;
+          }
+          return false;
+        }).map((key2) {
+          return buildTree(context, key2);
+        }).toList());
+  }
+
   @override
   Widget build(BuildContext context) {
-    // todo : add locations tree view
-
     if (locations == null) {
       return const Scaffold(
         body: CircularProgressIndicator(),
@@ -39,7 +59,12 @@ class _LocationsPageState extends State<LocationsPage> {
       appBar: AppBar(
         title: const Text("Locations"),
       ),
-      body: null,
+      body: TreeView(
+          nodes: locations!.keys
+              .where((key) => locations![key]!.parent == null)
+              .map((key) {
+        return buildTree(context, key);
+      }).toList()),
       floatingActionButton: FloatingActionButton(
         onPressed: () {
           // scan location code