component calling methods on another component

[dzacharias]

I have 2 components: Repository, and Document. A repository has an array of documents in variables scope. In each component I use the init() method to return an instance of the object. When a repository object is inited it generates a query of the documents that it contains, and loops through that, calling document.init() on each one and adding the resulting document object to the array.

When I init() a repository and use CFDUMP to view its documents array, I get an array of the correct length containing document objects. However, when I try to loop through the array and call a method like getTitle() on each document, I get empty strings. When I init() a document on its own, getTitle() works fine. Is there something basic that I'm forgetting here?

Let me know if you need to see the more code.

Don Zacharias
Sacramento, CA

[Dan_Bracuk]

I always use cfobject or createobject to return an instance of the cfc. Have you considered trying that?

[dzacharias]

Yeah I am using the pattern of an init() method that returns an instance of itself, so it can be chained to the createObject call. It seems to append an object, but I can't figure out how to work with that object. Any ideas? Thanks!!

[cf_dev2]

So where are you setting the other document properties like "Title"?

[dzacharias]

In the Document's init method, those properties are pulled from the database and set in variables scope. Then I use getTitle() etc to pull it back out.

And yeah those work fine when I'm just initing a document by itself, it's just when I am trying to init a bunch of documents in the repository's init method, and then call methods on those documents.

I feel like I'm missing something very basic here... Thanks!

[dzacharias · Accepted solution]

OMG I just nailed it. On the front end template, I tried using createObject each time through the loop of documents, and then setting the resulting empty document object to the document in the array. That worked. Thanks everybody!

[cf_dev2]

quote:

---

Originally posted by: dzacharias
OMG I just nailed it. On the front end template, I tried using createObject each time through the loop of documents, and then setting the resulting empty document object to the document in the array. That worked. Thanks everybody!

---

I'm not sure how that's different than what you were doing before 😉 but I'm glad its working for you.

<cfloop query="qDocuments">
<!--- create empty document object --->
<cfset document = createObject("component","Document").init(qDocuments.id)>
<!--- add empty document to array --->
<cfset arrayAppend(variables.documents,document)>
</cfloop>

[dzacharias]

In the Repository's init() method:
<cfloop query="qDocuments">
<!--- create empty document object --->
<cfset document = createObject("component","Document").init(qDocuments.id)>
<!--- add empty document to array --->
<cfset arrayAppend(variables.documents,document)>
</cfloop>

In the front end
<!--- show documents for this repository --->
<cfset arr_documents = repository.getDocuments()>
<cfloop from="1" to="#arrayLen(arr_documents)#" index="i">
<cfset doc = createObject("component","/docmanager_v2/components/Document")>
<cfset doc = arr_documents[ i ]>
<cfoutput>Title: #doc.getTitle()#, Summary: #doc.getSummary()#, Keywords: #doc.getKeywords()#<br></cfoutput>
</cfloop>

Now I'm doing createObject twice but I guess that makes sense... I wish I knew the principle at work here though...

[cf_dev2]

dzacharias,

Nevermind. I see from your post you are creating new instances.

[cf_dev2]

You shouldn't have to create the objects twice. I'm not even sure why that would work any differently, since in the end you're using the object from the array anyway.

<!--- the variable "doc" is overwritten in the next line --->
<cfset doc = createObject("component","/docmanager_v2/components/Document")>
<cfset doc = arr_documents[ i ]>

Also, are you properly VAR'ing your function local variables?

[dzacharias]

Actually you're right... I don't know why but I must not have tried it that way. Each time through the array I just copy the array element to a new variable and access the document methods through that variable and it works fine. Thanks again!

[cf_dev2]

Okay. Remove the second createObject() then. No point incurring the expense of createObject() if its not needed ;-)

> I just copy the array element to a new variable and access the document methods
> through that variable and it works fine.

IIRC its just a reference to the array element at that index, but yes that works 🙂