Make sure variable exist throughout the application - cakephp

Question

In my controller, I would like to set some values and have them exist (or live) throughout the different views in my app.
I read somewhere that I need to use beforeFilter function, but I am not sure if that is correct and how I go about doing that.
So in my controller I want to have
public function page1() {
$this->Model->setId('123');
}
public function page2() {
$this->Model->getId(); // would able to get the Id that was set from page1 function
$this->Model->setName('Bob');
}
public function page3() {
$this->Model->getId();
$this->Model->getName();
}
Let me know if you have questions.

Answer 1

To have this kind of "persistence" throughout the views, I guess the most simple approach is sessions.
Note that with the code you provided (I know is not a working example), you want the variable to be persistent inside a model, but that same model wont be maintained between actions of the same controller (or other controller for that matter).
You have to set that variable in sessions and retrieve it when you want to use it, or in the database and create methods in the model to get the last inserted id, for example.
So your code would be like
public function page1() {
$this->Session->write('id', '123');
}
public function page2() {
$this->Session->read('id');
$this->Session->write('name', 'Bob');
}
public function page3() {
$this->Session->read('id');
$this->Session->read('name');
}

Answer 2

Have a single model method that returns all your data in an array like
return array('varName' => $value, 'varName2' => $value2);
You can then call this model method from the controllers before filter and simply do
$this->set(ClassRegistry::init('MyModel')->commonViewVars());
If you would describe for what you think you need to do that I could give you a better advice like using requestAction() for example, this might be another option depending on what you're trying to do.
Depending on what data you want to pass to every page you should really consider to cache it. If its a menu for example cache it "forever" and just update the cache when the menu changes.