[ADD] barcodes: onchange-like mechanism to react to scans in form view

For a model to use it, it must :
- Inherit barcodes.barcode_events_mixin and override on_barcode_scanned(self, barcode)
- Add <field name=barcode_scanned widget=barcode_handler/> to each form view that
  should listen to barcode events and trigger on_barcode_scanned.

The method on_barcode_scanned works just like an onchange.

2 files changed, 27 insertions, 0 deletions

diff --git a/addons/barcodes/models/__init__.py b/addons/barcodes/models/__init__.py
new file mode 100644
index 00000000000..5c31ffd4a98
--- /dev/null
+++ b/addons/barcodes/models/__init__.py
@@ -0,0 +1,3 @@
+# -*- coding: utf-8 -*-
+
+import barcode_events_mixin
diff --git a/addons/barcodes/models/barcode_events_mixin.py b/addons/barcodes/models/barcode_events_mixin.py
new file mode 100644
index 00000000000..383e622c0a1
--- /dev/null
+++ b/addons/barcodes/models/barcode_events_mixin.py
@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+
+from openerp import models, fields, api
+
+class BarcodeEventsMixin(models.AbstractModel):
+    """ Mixin class for objects reacting when a barcode is scanned in their form views
+        which contains `<field name="_barcode_scanned" widget="barcode_handler"/>`.
+        Models using this mixin must implement the method on_barcode_scanned. It works
+        like an onchange and receives the scanned barcode in parameter.
+    """
+
+    _name = 'barcodes.barcode_events_mixin'
+
+    _barcode_scanned = fields.Char("Barcode Scanned", help="Value of the last barcode scanned.", store=False)
+
+    @api.onchange('_barcode_scanned')
+    def _on_barcode_scanned(self):
+        barcode = self._barcode_scanned
+        if barcode:
+            self._barcode_scanned = ""
+            return self.on_barcode_scanned(barcode)
+
+    def on_barcode_scanned(self, barcode):
+        raise NotImplementedError("In order to use barcodes.barcode_events_mixin, method on_barcode_scanned must be implemented")