protected function loadResourceForBlockName($cacheKey, FormView $view, $blockName)
{
// The caller guarantees that $this->resources[$cacheKey][$block] is
// not set, but it doesn't have to check whether $this->resources[$cacheKey]
// is set. If $this->resources[$cacheKey] is set, all themes for this
// $cacheKey are already loaded (due to the eager population, see doc comment).
if (isset($this->resources[$cacheKey])) {
// As said in the previous, the caller guarantees that
// $this->resources[$cacheKey][$block] is not set. Since the themes are
// already loaded, it can only be a non-existing block.
$this->resources[$cacheKey][$blockName] = false;
return false;
}
// Recursively try to find the block in the themes assigned to $view,
// then of its parent view, then of the parent view of the parent and so on.
// When the root view is reached in this recursion, also the default
// themes are taken into account.
// Check each theme whether it contains the searched block
if (isset($this->themes[$cacheKey])) {
for ($i = count($this->themes[$cacheKey]) - 1; $i >= 0; --$i) {
$this->loadResourcesFromTheme($cacheKey, $this->themes[$cacheKey][$i]);
// CONTINUE LOADING (see doc comment)
}
}
// Check the default themes once we reach the root view without success
if (!$view->parent) {
for ($i = count($this->defaultThemes) - 1; $i >= 0; --$i) {
$this->loadResourcesFromTheme($cacheKey, $this->defaultThemes[$i]);
// CONTINUE LOADING (see doc comment)
}
}
// Proceed with the themes of the parent view
if ($view->parent) {
$parentCacheKey = $view->parent->vars[self::CACHE_KEY_VAR];
if (!isset($this->resources[$parentCacheKey])) {
$this->loadResourceForBlockName($parentCacheKey, $view->parent, $blockName);
}
// EAGER CACHE POPULATION (see doc comment)
foreach ($this->resources[$parentCacheKey] as $nestedBlockName => $resource) {
if (!isset($this->resources[$cacheKey][$nestedBlockName])) {
$this->resources[$cacheKey][$nestedBlockName] = $resource;
}
}
}
// Even though we loaded the themes, it can happen that none of them
// contains the searched block
if (!isset($this->resources[$cacheKey][$blockName])) {
// Cache that we didn't find anything to speed up further accesses
$this->resources[$cacheKey][$blockName] = false;
}
return false !== $this->resources[$cacheKey][$blockName];
}
