I have TeamsPage class and Team class. I am trying to figure out how to pre-populate the form with the data from the database based on the ID that was passed in the URL. Below is the code of my attempt, I tried to pass in the ID via template but that did not work. How else can I accomplish this? I would prefer if there was a way to pass the team as an object that I already have in the edit method so that I don't have to hit the database twice. Is there a way to do this?

TeamsPage:

<?php
class TeamsPage extends Page {
	private static $has_many = array (
		'Teams' => 'Team',
	);
	public function getCMSFields() {
		$fields = parent::getCMSFields();
		$fields->addFieldToTab('Root.Teams', GridField::create(
			'Teams',
			'Teams on this page',
			$this->Teams(),
			GridFieldConfig_RecordEditor::create()
		));
		return $fields;
	}
}
class TeamsPage_Controller extends Page_Controller {
    private static $allowed_actions = array (
        'show', 'edit', 'EditTeamForm'
    );

    public function EditTeamForm($teamId){
        $fields = new FieldList(
            new TextField('TeamName'),
            new TextareaField('TeamDescription')
        );
        $actions = new FieldList(
            new FormAction('EditTeam', 'Save Changes')
        );
        $requiredFields = new RequiredFields(array('TeamName','TeamDescription'));
        $form = new Form($this, 'EditTeamForm', $fields, $actions, $requiredFields);
        $form->setFormMethod('POST', true);

        $data = Session::get("FormData.{$form->getName()}.data");
        $team = Team::get()->byID($teamId);
        return $data ? $form->loadDataFrom($data) : $form->loadDataFrom($team);
    }

    public function show(SS_HTTPRequest $request) {
        $team = Team::get()->byID($request->param('ID'));

        if(!$team) {
            return $this->httpError(404,'That team could not be found');
        }

        return array (
            'Team' => $team
        );
    }

    public function edit(SS_HTTPRequest $request){
        $team = Team::get()->byID($request->param('ID'));

        if(!$team) {
            return $this->httpError(404,'That team could not be found');
        }

        return array (
            'Team' => $team
        );
    }
}

Team:

<?php
class Team extends DataObject {
	private static $db = array(
        'TeamCaptain' => 'Int',
        'TeamName' => 'Varchar',
        'TeamDescription' => 'Text'
    );
	private static $has_one = array (
		'Photo' => 'Image',
		'TeamsPage' => 'TeamsPage'
	);
	private static $summary_fields = array (
		'GridThumbnail' => '',
		'TeamCaptain' => 'Team Captain',
		'TeamName' => 'TeamName',
		'TeamDescription' => 'Team Description',
	);
	public function getGridThumbnail() {
		if($this->Photo()->exists()) {
			return $this->Photo()->SetWidth(100);
		}
		return '(no image)';
	}
	public function getCMSFields() {
		$fields = FieldList::create(
			TextField::create('TeamCaptain'),
			TextField::create('TeamName'),
			TextareaField::create('TeamDescription'),
			$uploader = UploadField::create('Photo')
		);
		$uploader->setFolderName('teams-photos');
		$uploader->getValidator()->setAllowedExtensions(array(
			'png','gif','jpeg','jpg'
		));
		return $fields;
	}

    public function Link() {
        return $this->TeamsPage()->Link('show/'.$this->ID);
    }
}

TeamsPage_edit.ss

<% if GetMember() %>
    Welcome $getMember.FirstName<br />
    $EditTeamForm()
    $ID
    <a href="home">Back to Home</a>
<% else %>
    $GoToLogin()
<% end_if %>