How to save multiple values entered into ListBoxField and loop through values?

问题

I want to be able to associate team members to a project using the ListBoxField . I have a ProjectHolder which has Project pages as it's children. I also have a TeamHolder which has TeamPage's as its children.

I want to be able to save multiple team members in the ListBoxField and then loop through them on a Project page. I also want to be able to link to the team members pages. e.g

<% loop $TeamMemberNames %>
    <a href="$Link">$Name</a>
<% end_loop %>

My Current code:

TeamPage.php

class TeamPage extends Page
{
    private static $db = array(
        'Name' => 'Varchar(255)',
    );

    public function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab('Root.TeamMembers', TextField::create('Name'));

        return $fields;
    }
}

Project.php

class Project extends Page
{
    private static $db = array(
        'Name' => 'Varchar(255)',
    );

    public function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab('Root.TeamMembers', TextField::create('Name'));

        $fields->addFieldToTab('Root.TeamMembers', ListBoxField::create(
            'TeamPage',
            'Select Team Members for project',
            TeamPage::get()->map("ID", "Name")->toArray()
        )->setMultiple(true));

        return $fields;
    }

}

Screenshot:

I can pull through the names from the TeamPage Object into the ListBoxField however after selecting the names I need a way to save the multiple values and also get the Link so I can link to the appropriate team members pages that are listed.

回答1:

To save data to the database we must first define a relationship to the data in our class. In this case we want to create a $many_many relationship between Project and TeamPage.

In the Project class we add a $many_many relationship to TeamPage. Here, the relationship name is TeamPages.

When creating the ListBoxField we pass the TeamPages relationship name so the field knows where to save this data:

Project.php

class Project extends Page
{
    private static $db = array(
        'Name' => 'Varchar(255)'
    );

    private static $many_many = array(
        'TeamPages' => 'TeamPage'
    );

    public function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab('Root.TeamMembers', TextField::create('Name'));

        $fields->addFieldToTab('Root.TeamMembers', ListBoxField::create(
            'TeamPages',
            'Select Team Members for project',
            TeamPage::get()->map('ID', 'Name')->toArray()
        )->setMultiple(true));

        return $fields;
    }
}

Now in our template we can loop through a Project's $TeamPages by calling the following:

Template

<% loop $TeamPages %>
    <a href="$Link">$Name</a>
<% end_loop %>

If we would like a TeamPage to be able to access it's related Projects we can add a $belongs_many_many to the TeamPage class to point back to the Project class. You can also add a ListBoxField to control Projects from the TeamPage.

TeamPage.php

class TeamPage extends Page
{
    private static $db = array(
        'Name' => 'Varchar(255)'
    );

    private static $belongs_many_many = array(
        'Projects' => 'Project'
    );

    public function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab('Root.TeamMembers', TextField::create('Name'));

        $fields->addFieldToTab('Root.TeamMembers', ListBoxField::create(
            'Projects',
            'Select project for this team page',
            Project::get()->map('ID', 'Name')->toArray()
        )->setMultiple(true));

        return $fields;
    }
}

Something to note is TeamPage and Project both extend Page. This means both classes inherit a Title field. I would suggest using Title instead of Name, unless you have a specific reason to do so.

This would make the code:

Project.php

class Project extends Page
{
    private static $many_many = array(
        'TeamPages' => 'TeamPage'
    );

    public function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab('Root.TeamMembers', ListBoxField::create(
            'TeamPages',
            'Select Team Members for project',
            TeamPage::get()->map('ID', 'Title')->toArray()
        )->setMultiple(true));

        return $fields;
    }
}

TeamPage.php

class TeamPage extends Page
{
    private static $belongs_many_many = array(
        'Projects' => 'Project'
    );

    public function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab('Root.Projects', ListBoxField::create(
            'Projects',
            'Select project for this team page',
            Project::get()->map('ID', 'Title')->toArray()
        )->setMultiple(true));

        return $fields;
    }
}

Template

<% loop $TeamPages %>
    <a href="$Link">$Title</a>
<% end_loop %>

来源：https://stackoverflow.com/questions/33647047/how-to-save-multiple-values-entered-into-listboxfield-and-loop-through-values