Views

Views are HTML content that can be rendered inside of a layout or by themselves. They can be either rendered on demand or by being set by an event handler. Views can also produce any type of content apart from HTML like JSON/XML/WDDX via our view renderer that we will discover also. So get ready for some rendering goodness!

Setting Views For Rendering

Usually, event handlers are the objects in charge of setting views for rendering. However, ANY object that has access to the request context object can do this also. This is done by using the setView() method in the request context object.

Setting a view does not mean that it gets rendered immediately. It means that it is deposited in the request context. The framework will later on in the execution process pick those variables up and do the actual rendering. To do immediate rendering you will use the inline rendering methods describe later on.

handlers/main.cfc

component
{

    function index(event,rc,prc){
        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();
        // set the view for rendering
        event.setView( "general/index" );

    }

}

We use the setView() method to set the view views/general/index.cfm to be rendered. Now the cool thing about this, is that we can override the view to be rendered anytime during the flow of the request. So the last process to execute the setView() method is the one that counts. Also notice a few things:

• No .cfm extension is needed.

• You can traverse directories by using / like normal cfinclude notation.

• The view can exist in the conventions directory views or in your configured external locations

• You did not specify a layout for the view, so the application's default layout (main.cfm) will be used.

It is best practice that view locations should simulate the event. So if the event is general.index, there should be a general folder in the root views folder with a view called index.cfm.

Let's look at the view code:

main/index.cfm

<cfoutput>
<h1>My Cool Data</h1>
#html.table( data=prc.myQuery, class="table table-striped table-hover" )#

</cfoutput>

I am using our cool HTML Helper class that is smart enough to render tables, data, HTML 5 elements etc and even bind to ColdFusion ORM entities.

Views With No Layout

So what happens if I DO NOT want the view to be rendered within a layout? Am I doomed? Of course not, just use the same method with the noLayout argument or event.noLayout() method:

component{

    function index(event,rc,prc){
        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();
        // set the view for rendering
        event.setView( view="general/index", noLayout=true );
    }

    function index(event,rc,prc){
        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();
        // set the view for rendering
        event.setView( "general/index" ).noLayout();
    }
}

Views With Layouts

If you need the view to be rendered in a specific layout, then use the layout argument or the setLayout() method:

component name="general"{

    function index(event,rc,prc){
        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();
        // set the view for rendering
        event.setView( view="general/index", layout="Ajax" );
    }

    function index(event,rc,prc){
        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();
        // set the view for rendering
        event.setView( "general/index" ).setLayout( "Ajax" );
    }

}

Views From Modules

If you need the set a view to be rendered from a specific ColdBox Module then use the module argument alongside any other argument combination:

component name="general"{

    function index(event,rc,prc){

        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();
        // set the view for rendering
        event.setView( view="general/index", module="shared-views" );

    }

}

Render Nothing

You can also tell the renderer to not render back anything to the user by using the event.noRender() method. Maybe you just took some input and need to gracefully shutdown the request into the infamous white screen of death.

component name="general"{

    function saveData(event,rc,prc){
        // do your work here …..

        // set for no render
        event.noRender();
    }

}

Implicit Views

You can also omit the explicit event.setView() if you want, ColdBox will then look for the view according to the executing event's syntax by convention. So if the incoming event is called general.index and no view is explicitly defined in your handler, ColdBox will look for a view in the general folder called index.cfm. That is why we recommend trying to match event resolution to view resolution even if you use or not implicit views.

Tip: This feature is more for conventions purists than anything else. However, we do recommend as best practice to use explicitly declare the view to be rendered when working with team environments as everybody will know what happens.

component name="general"{

    function index(event,rc,prc){
        // call some model for data and put into the request collection
        prc.myQuery = getInstance('MyService').getData();    
    }

}

Caution If using implicit views, please note that the name of the view will ALWAYS be in lower case. So please be aware of this limitation. I would suggest creating URL Mappings with explicit event declarations so case and location can be controlled. When using implicit views you will also loose fine rendering control.

Disabling Implicit Views

You can also disable implicit views by using the coldbox.implicitViews configuration setting in your config/ColdBox.cfc. This is useful as implicit lookups are time-consuming.

coldbox.implicitViews = false;

Case Sensitivity

The ColdBox rendering engine can also be tweaked to use case-insensitive or sensitive implicit views by using the coldbox.caseSensitiveImplicitViews directive in your config/ColdBox.cfc. The default is to turn all implicit views to lower case, so the value is always false.

coldbox.caseSensitiveImplicitViews = true;