Implements hook_field_instance_settings_form().
function image_field_instance_settings_form($field, $instance) {
$settings = $instance['settings'];
// Use the file field instance settings form as a basis.
$form = file_field_instance_settings_form($field, $instance);
// Add maximum and minimum resolution settings.
$max_resolution = explode('x', $settings['max_resolution']) + array(
'',
'',
);
$form['max_resolution'] = array(
'#type' => 'item',
'#title' => t('Maximum image resolution'),
'#element_validate' => array(
'_image_field_resolution_validate',
),
'#weight' => 4.1,
'#field_prefix' => '<div class="container-inline">',
'#field_suffix' => '</div>',
'#description' => t('The maximum allowed image size expressed as WIDTHxHEIGHT (e.g. 640x480). Leave blank for no restriction. If a larger image is uploaded, it will be resized to reflect the given width and height. Resizing images on upload will cause the loss of <a href="@url">EXIF data</a> in the image.', array(
'@url' => 'http://en.wikipedia.org/wiki/Exchangeable_image_file_format',
)),
);
$form['max_resolution']['x'] = array(
'#type' => 'number',
'#title' => t('Maximum width'),
'#title_display' => 'invisible',
'#default_value' => $max_resolution[0],
'#min' => 1,
'#field_suffix' => ' x ',
);
$form['max_resolution']['y'] = array(
'#type' => 'number',
'#title' => t('Maximum height'),
'#title_display' => 'invisible',
'#default_value' => $max_resolution[1],
'#min' => 1,
'#field_suffix' => ' ' . t('pixels'),
);
$min_resolution = explode('x', $settings['min_resolution']) + array(
'',
'',
);
$form['min_resolution'] = array(
'#type' => 'item',
'#title' => t('Minimum image resolution'),
'#element_validate' => array(
'_image_field_resolution_validate',
),
'#weight' => 4.2,
'#field_prefix' => '<div class="container-inline">',
'#field_suffix' => '</div>',
'#description' => t('The minimum allowed image size expressed as WIDTHxHEIGHT (e.g. 640x480). Leave blank for no restriction. If a smaller image is uploaded, it will be rejected.'),
);
$form['min_resolution']['x'] = array(
'#type' => 'number',
'#title' => t('Minimum width'),
'#title_display' => 'invisible',
'#default_value' => $min_resolution[0],
'#min' => 1,
'#field_suffix' => ' x ',
);
$form['min_resolution']['y'] = array(
'#type' => 'number',
'#title' => t('Minimum height'),
'#title_display' => 'invisible',
'#default_value' => $min_resolution[1],
'#min' => 1,
'#field_suffix' => ' ' . t('pixels'),
);
// Remove the description option.
unset($form['description_field']);
// Add title and alt configuration options.
$form['alt_field'] = array(
'#type' => 'checkbox',
'#title' => t('Enable <em>Alt</em> field'),
'#default_value' => $settings['alt_field'],
'#description' => t('The alt attribute may be used by search engines, screen readers, and when the image cannot be loaded.'),
'#weight' => 9,
);
$form['alt_field_required'] = array(
'#type' => 'checkbox',
'#title' => t('<em>Alt</em> field required'),
'#default_value' => $settings['alt_field_required'],
'#weight' => 10,
'#states' => array(
'visible' => array(
':input[name="instance[settings][alt_field]"]' => array(
'checked' => TRUE,
),
),
),
);
$form['title_field'] = array(
'#type' => 'checkbox',
'#title' => t('Enable <em>Title</em> field'),
'#default_value' => $settings['title_field'],
'#description' => t('The title attribute is used as a tooltip when the mouse hovers over the image.'),
'#weight' => 11,
);
$form['title_field_required'] = array(
'#type' => 'checkbox',
'#title' => t('<em>Title</em> field required'),
'#default_value' => $settings['title_field_required'],
'#weight' => 12,
'#states' => array(
'visible' => array(
':input[name="instance[settings][title_field]"]' => array(
'checked' => TRUE,
),
),
),
);
// Add the default image to the instance.
$form['default_image'] = array(
'#title' => t('Default image'),
'#type' => 'managed_file',
'#description' => t("If no image is uploaded, this image will be shown on display and will override the field's default image."),
'#default_value' => $settings['default_image'],
'#upload_location' => $field['settings']['uri_scheme'] . '://default_images/',
);
return $form;
}