Programmatically select image style for use with custom file entity view mode

Question

I have created an empty custom view mode for file entities with hook_entity_info_alter().

I would like to programmatically select settings for it, so that they can be deployed without a user having to go to the file entity display settings GUI and select "image" for type of file display and "original size" for the image style.

I cannot do this with hook_entity_view_mode_alter() because that appears to only fire for nodes, not for file entities.

How can I programmatically set the display settings for my custom view mode for file entities?

Answer 1

Sounds like something like this should work for you, to set the file display for the image file type, view mode name VIEW_MODE (replace with your custom view mode), to display original image. It either adds a new file display or updates an existing one:

$displays = file_displays_load('image', 'VIEW_MODE', TRUE);
$formatter = 'file_field_image';
if (array_key_exists($formatter, $displays)) {
  $display = $displays[$formatter];
}
else {
  $display = (object) array(
    'api_version' => 1,
    'name' => 'image__VIEW_MODE__' . $formatter,
  );
}
$display->status = 1;
$display->settings['image_style'] = '';
file_display_save($display);