kinglozzer/BetterButtonBetterNestedForm.php

## _config.yml
GridFieldDetailForm_ItemRequest:
  extensions:
    - GridFieldBetterButtonsBetterItemRequestExtension

## BetterButtonBetterNestedForm.php
<?php

class BetterButtonBetterNestedForm extends BetterButtonNestedForm
{
    public function getButtonLink()
    {
        Requirements::javascript('mysite/javascript/GridFieldBetterButtonsNestedForm.js');
        $link = 'betternestedform?action=' . $this->actionName;
        return $this->gridFieldRequest->Link($link);
    }
}

## BetterButtonsBetterNestedFormRequest.php
<?php

class BetterButtonsBetterNestedFormRequest extends BetterButtonsNestedFormRequest
{
    public function Link()
    {
        return $this->controller->Link('betternestedform');
    }

    public function nestedFormSave($data, $form, $request)
    {
        $formAction = $this->getFormActionFromRequest($request);
        $actionName = $formAction->getButtonName();

        $result = $this->record->$actionName($data, $form, $request);
        if ($result) {
            $this->form->sessionMessage($result, 'good');
        }

        return <<<HTML
<span class="force-reload">Loading, please wait...</span>
HTML
        ;
    }
}

## GridFieldBetterButtonsBetterItemRequestExtension.php
<?php

class GridFieldBetterButtonsBetterItemRequestExtension extends Extension
{
    private static $allowed_actions = [
        'betternestedform'
    ];

    /**
     * Handles all custom action from DataObjects and hands them off to a sub-controller.
     * e.g. /betternestedform?action=myDataObjectAction
     *
     * @param SS_HTTPRequest $request
     * @return SS_HTTPResponse
     */
    public function betternestedform(SS_HTTPRequest $request)
    {
        $req = BetterButtonsBetterNestedFormRequest::create($this, $this->owner, $this->owner->ItemEditForm());
        return $req->handleRequest($request, DataModel::inst());
    }
}

## GridFieldBetterButtonsNestedForm.js
(function($) {
	$.entwine('ss', function($) {
		$('.better-button-dialog iframe').entwine({
			onmatch: function() {
				var self = this;

				self.on('load', function() {
					if (self.contents().find('.force-reload').length) {
						window.location.reload(true);
					}
				});
			}
		})
	});
})(jQuery);
	GridFieldDetailForm_ItemRequest:
	extensions:
	- GridFieldBetterButtonsBetterItemRequestExtension
	<?php

	class BetterButtonBetterNestedForm extends BetterButtonNestedForm
	{
	public function getButtonLink()
	{
	Requirements::javascript('mysite/javascript/GridFieldBetterButtonsNestedForm.js');
	$link = 'betternestedform?action=' . $this->actionName;
	return $this->gridFieldRequest->Link($link);
	}
	}
	<?php

	class BetterButtonsBetterNestedFormRequest extends BetterButtonsNestedFormRequest
	{
	public function Link()
	{
	return $this->controller->Link('betternestedform');
	}

	public function nestedFormSave($data, $form, $request)
	{
	$formAction = $this->getFormActionFromRequest($request);
	$actionName = $formAction->getButtonName();

	$result = $this->record->$actionName($data, $form, $request);
	if ($result) {
	$this->form->sessionMessage($result, 'good');
	}

	return <<<HTML
	<span class="force-reload">Loading, please wait...</span>
	HTML
	;
	}
	}
	<?php

	class GridFieldBetterButtonsBetterItemRequestExtension extends Extension
	{
	private static $allowed_actions = [
	'betternestedform'
	];

	/**
	* Handles all custom action from DataObjects and hands them off to a sub-controller.
	* e.g. /betternestedform?action=myDataObjectAction
	*
	* @param SS_HTTPRequest $request
	* @return SS_HTTPResponse
	*/
	public function betternestedform(SS_HTTPRequest $request)
	{
	$req = BetterButtonsBetterNestedFormRequest::create($this, $this->owner, $this->owner->ItemEditForm());
	return $req->handleRequest($request, DataModel::inst());
	}
	}
	(function($) {
	$.entwine('ss', function($) {
	$('.better-button-dialog iframe').entwine({
	onmatch: function() {
	var self = this;

	self.on('load', function() {
	if (self.contents().find('.force-reload').length) {
	window.location.reload(true);
	}
	});
	}
	})
	});
	})(jQuery);