Store data from example panel (#5986)

* Fix errors in variable names of examples

* Added drop down example

* Added drop down example

* Fixed picture name

* Fixed context variable in purchase order report

* Store data from example panel

* Store data from example panel

* Store data from example panel

docs/docs/extend/plugins/panel.md

@@ -191,6 +191,7 @@ class ExamplePanel(PanelMixin, InvenTreePlugin, UrlsMixin):
     def get_custom_panels(self, view, request):
         panels = []
         if isinstance(view, BuildDetail):
+	    self.build=view.get_object()
 	    panels.append({
 		'title': 'Example Info',
 		'icon': 'fa-industry',
@@ -331,6 +332,7 @@ from company.models import Company
     def get_custom_panels(self, view, request):
         panels = []
         if isinstance(view, BuildDetail):
+	    self.build=view.get_object()
             self.companies=Company.objects.filter(is_supplier=True)
             panels.append({
             ...
@@ -352,3 +354,19 @@ by looping.
 
 The value of the select is the pk of the company. It can simply be added to the
 json container and transferred to the plugin.
+
+#### Store the Data
+I case you plugin needs to store data permanently, InvenTree has a nice feature called
+[metadata](metadata.md). You can easily store your values by adding a few lines
+to the do_something function.
+code:
+
+```python
+    def do_something(self, request):
+
+        data=json.loads(request.body)
+        print('Data received:', data)
+	for key in data:
+	    self.build.metadata[key]=data[key]
+	self.build.save()
+```