yes you can activate it using an email, again via action, and you dont need an extension, because you are a programmer, and you must do that yourself !
First at all you application object muest exists obviously, in state 'not approved', then, look at diagram at top, when you notify the new application record to your admin, then include a full action URL that automatically when called then activate the record.
"hello admin you have new pending approval, click here:
http://www.yourserver.com/index.php?r=application/approvebyemail&id=123"
in your application controller:
public function actionApprovedByEmail($id) {
$model = $this->loadModel($id);
$model->status = 1; // approved
$model->save();
$this->redirect("index.php?r=application/approvedsuccessfull");
}
public function actionApproveSuccessfull() {
$this->renderText("<h1>Hello admin, the application was successfully approved</h1><p>Thanks !</p>");
}
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