In your view: $this->Flash->render('somekey');
Will default to flash if no param is passed
You can pass additional information into the flash message generation. This allows you
to consolidate all the parameters for a given type of flash message into the view.
echo $this->Flash->render('flash', ['params' => ['name' => $user['User']['name']]]);
This would pass the current user's name into the flash message, so you could create personalized
messages without the controller needing access to that data.
Lastly you can choose the element that is used for rendering the flash message. Using
custom elements allows you to fully customize how flash messages are generated.
echo $this->Flash->render('flash', ['element' => 'my_custom_element']);
If you want to use an element from a plugin for rendering your flash message
you can use the dot notation for the plugin's element name:
echo $this->Flash->render('flash', [
'element' => 'MyPlugin.my_custom_element',
]);