Dynamicky formular

Pokousim se udelat takovy formular, kde kdyz vyberu polozku z jednoho selectu, tak se podle toho aktualizuje obsah druheho selectu. Zatim mam nasledujici kod, ale to pada na tom, ze onFilterClicked() se spusti az po
createComponentFilterForm(), cili do selectu se nactou hodnoty, ktere neodpovidaji te zvolene ve formulari.

<?php
	protected function createComponentFilterForm($name) {
		$form = new AppForm($this, $name);
		$form->addSelect('cbGrammar', 'Grammar:', GrammarModel::getGrammarPairsByPack('arithmetic'))
			->setDefaultValue($this->listSettings->grammarId);
		$form->addSelect('cbService', 'Service:', ServicesModel::getServicePairsByGrammar($this->listSettings->grammarId))
			->setDefaultValue($this->listSettings->serviceId);
		$form->addSelect('cbPopulation', 'Population:', $this->model->getPopulationPairsByService($this->listSettings->serviceId))
			->setDefaultValue($this->listSettings->populationId);
		$form->addSelect('cbGeneration', 'Generation:', $this->model->getGenerationPairsByPopulation($this->listSettings->populationId))
			->setDefaultValue($this->listSettings->generation);
		$form->addSubmit('bFilter', 'Filter')->onClick[] = array($this, 'onFilterClicked');
		return $form;
	}
?>

<?php
	public function onFilterClicked(SubmitButton $button) {
		$this->listSettings->grammarId = $this['filterForm']['cbGrammar']->value;
		$this->listSettings->serviceId = $this['filterForm']['cbService']->value;
		$this->listSettings->populationId = $this['filterForm']['cbPopulation']->value;
		$this->listSettings->generation = $this['filterForm']['cbGeneration']->value;
	}
?>

V zasade je to cele filtr, kde kdyz v prvnim selectu neco vyberu tak se to zobrazi v datagridu, a soucasne se nacte obsah dalsiho selectu. Pokud to dal upresnim v dalsim selectu, zase se aktualizuje datagrid a nabidne se dalsi select s upresnenim, atd…
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