[SalesForce] the standard Controller, and what can it access

Suppose I have this URL where a VF page points to a record: https://c.cs16.visual.force.com/apex/oppTest?id=006a0000012Wb4s . In my VF below, I get that the standard controller gets that record from the sObject. In my VF page, what are the limits to what I can access? Standard fields, and custom ones seem to be ok. It also lets me traverse relationships ( say from Opp –> Account–> User …). Can I also get children records? if so how?

<apex:page standardController="Opportunity" >
<apex:outputField value="{!Opportunity.name}"/>
<apex:outputField value="{!Opportunity.Account.createdby.name}"/>
<apex:outputField value="{!Opportunity.Account.createdby.custom__c}"/>
<apex:outputField value="{!Opportunity.CreatedBy.name}"/>

</apex:page>

Best Answer

StandardController, or, more formally, ApexPages.StandardController, is a system class that exposes functions for various things you'd want to do with a record.

It can add additional fields to the default record query (addFields) or reset the internal state (reset), return to the last page without performing any action (cancel), save and go on (save), return an edit page (edit), get the record (getRecord) or record's ID (getId), and return a link to the detail page (view).

The primary purpose of this class is to emulate UI actions programmatically, and extend the query parameters for an extension class in a Visualforce page. StandardController is responsible for building the SOQL that will eventually be used by the Visualforce page to render the page.

Normal SOQL limits apply, meaning you can only go "up" four relationships, and "down" one relationship. This means you can't get the parent's parent's parent's parent's parent's name, nor can you get grandchildren records. Note that you don't explicitly specify which relationships you want to query normally, as they are derived from the Visualforce code.

See the documentation for StandardController for further explanation of this class.

Curiously, the last time I played around with this class, I noticed that calling save() does not increase the DML rows or DML count for a transaction, but saving records this way is inefficient and not recommended for bulk saving.

Related Solutions

[SalesForce] PageReference from embedded Visualforce page becomes inlined

I managed to hack my way around it by using JavaScript in the command button oncomplete to do the redirection from the top level window.

Simplified Page:

My reality is a bit more complicated as the Command button is a dynamic Visualforce component.

E.g. public PageReference stubAction() { return null; }

public PageReference editDynamicProperties() {
    PageReference editpr = Page.AnotherPage;

    Map<string, string> params = editpr.getParameters();
    params.put('oppId', opportunityFromController.Id);

    editpr.setRedirect(true);
    return editpr;
}

public Component.Apex.OutputPanel getDynamicPropertyControls() {
    //...

    Component.Apex.PageBlockButtons pbButtons = new Component.Apex.PageBlockButtons();
    pb.childComponents.add(pbButtons);

    Component.Apex.CommandButton editCommandButton = new Component.Apex.CommandButton();
    editCommandButton.value='Edit';
    //editCommandButton.expressions.action = '{!editDynamicProperties}';
    editCommandButton.expressions.action = '{!stubAction}';

    editCommandButton.rerender= new Set<string>{'dynamicForm'};
    editCommandButton.oncomplete= 'window.top.location.href = \''+editDynamicProperties().getUrl()+'\'';
    pbButtons.childComponents.add(editCommandButton);

    //...
}

UPDATE: Apparently I've come across this problem before. See Visualforce Page embedded in a detail page that needs to redirect to other page That question had a very similar answer by JCD, but the redirection was handled by the rerendered component.

[SalesForce] Pagination using standardset controller and ability to remove rows from list

If you still query for the large list it will be in memory at some point and you will still break the heap size limit. You would need to use the Database.QueryLocator version of the StandardSetController to avoid that. After each successful remove you will need to query the data back into the QueryLocator.

public ApexPages.StandardSetController setCon { get; set; }

public YourConstructor() {
    refreshStandardSetController();
}

public PageReference remove() {
    // remove from DB or possibly just collect Ids to be removed later
    // depending on your requirements.
    refreshStandardSetController();
}

private void refreshStandardSetController() {
    // save off the current page to attempt
    // to keep the user on the same page after the query...
    Integer currentPage = setCon != null ? setCon.getPageNumber() : 1;

    setCon = new ApexPages.StandardSetController(
        Database.getQueryLocator([
            Select Id, Name
            From Account
            /* Where possible where clause */
            Order by Name
    ]);
    // possibly set the page size to something other than default 20...
    setCon.setPageSize(YOUR_CUSTOM_PAGE_SIZE):

    // keep the user on the same page if possible
    Integer newPage = currentPage <= getTotalPages() ? currentPage : setCon.getPageNumber();
    setCon.setPageNumber(newPage);
}

private Integer getTotalPages() {
    return (Integer) Math.ceil(
        Double.valueOf(setCon.getResultSize()) / setCon.getPageSize());
}

See the StandardSetController docs for more information.

Best Answer

Related Solutions

[SalesForce] PageReference from embedded Visualforce page becomes inlined

[SalesForce] Pagination using standardset controller and ability to remove rows from list

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