Note: this list is generated by looking for the string for this theme hook, so it may include some references that are not actually using this theme hook.

ajax_example_form_node_callback in modules/examples/ajax_example/ajax_example_node_form_alter.inc
Returns changed part of the form.
ajax_example_form_node_form_alter in modules/examples/ajax_example/ajax_example_node_form_alter.inc
Implements hook_form_FORM_ID_alter().
authorize_filetransfer_form in core/includes/authorize.inc
Form constructor for the file transfer authorization form.
backdrop_common_theme in core/includes/common.inc
Provides theme registration for themes across .inc files.
BlockLegacy::form in core/modules/layout/includes/block_legacy.class.inc
Build the settings form for editing this block.
color_form_system_theme_settings_alter in core/modules/color/color.module
Implements hook_form_FORM_ID_alter().
contact_settings_form in core/modules/contact/contact.admin.inc
Contact settings form.
DashboardWelcomeBlock::getContent in core/modules/dashboard/includes/block.welcome.inc
Return the content of a block.
field_default_form in core/modules/field/field.form.inc
Creates a form element for a field and can populate it with a default value.
field_ui_display_form in core/modules/field_ui/field_ui.admin.inc
Form constructor for the field display settings for a given display mode.
filter_admin_format_form in core/modules/filter/filter.admin.inc
Form constructor for the text format add/edit form.
filter_process_format in core/modules/filter/filter.module
Expands an element into a base element with text format selector attached.
install_settings_form in core/includes/install.core.inc
Form constructor for a form to configure and rewrite settings.php.
language_admin_add_form in core/modules/language/language.admin.inc
User interface for the language addition screen.
LayoutFlexibleTemplate::__construct in core/modules/layout/includes/layout_flexible.class.inc
Constructor for a LayoutFlexibleTemplate class.
LayoutFlexibleTemplateTest::testLayoutFlexibleTemplates in core/modules/layout/tests/layout.test
Test that layout templates may be enabled and disabled.
layout_block_add_page in core/modules/layout/layout.admin.inc
Menu callback; Display a list of blocks to be added to a layout.
layout_block_configure_form in core/modules/layout/layout.admin.inc
Form callback; Add or edit a block within a layout.
layout_block_list in core/modules/layout/layout.admin.inc
Menu callback; Lists all blocks and their modules.
layout_condition_add_form in core/modules/layout/layout.admin.inc
Form callback; Displays form for adding new conditions to a layout or block.
layout_flexible_template_change_region_style in core/modules/layout/layout.flexible.inc
Submit handler for the change region style button on the layout_flexible_template_edit_row_form().
layout_flexible_template_edit_row_form in core/modules/layout/layout.flexible.inc
Form to add or edit a row on a flexible template.
layout_flexible_template_edit_row_form_submit in core/modules/layout/layout.flexible.inc
Submit handler for layout_flexible_template_edit_row_form().
layout_flexible_template_region_style_select in core/modules/layout/layout.flexible.inc
Form to select the region widths for a flexible template.
layout_menu_item_form in core/modules/layout/layout.admin.inc
Form callback; Configure a layout menu item.
layout_preprocess_layout in core/modules/layout/layout.theme.inc
Prepares variables for layout templates.
layout_settings_form in core/modules/layout/layout.admin.inc
Render the settings form for layout.
menu_form_node_form_alter in core/modules/menu/menu.module
Implements hook_form_BASE_FORM_ID_alter().
node_preview in core/modules/node/node.pages.inc
Generates a node preview.
RenderElementTypesTestCase::testContainer in core/modules/simpletest/tests/theme.test
Tests system #type 'container'.
search_form in core/modules/search/search.module
Builds a search form.
system_element_info in core/modules/system/system.module
Implements hook_element_info().
system_element_info in core/modules/system/system.module
Implements hook_element_info().
system_element_info in core/modules/system/system.module
Implements hook_element_info().
system_modules in core/modules/system/system.admin.inc
Menu callback; provides module enable/disable interface.
system_performance_settings in core/modules/system/system.admin.inc
Form builder; Configure site performance settings.
system_regional_settings in core/modules/system/system.admin.inc
Form builder; Configure the site regional settings.
system_site_information_settings in core/modules/system/system.admin.inc
Form builder; The general site information form.
template_preprocess_views_view_mapping_test in core/modules/views/tests/views_test/views_test.module
Implements hook_preprocess_HOOK() for theme_views_view_mapping_test().
theme_options in core/modules/field/modules/options/options.theme.inc
Theme an options element.
user_account_form in core/modules/user/user.module
Helper function to add default user account fields to user registration and edit form.
user_admin_settings in core/modules/user/user.admin.inc
Form builder; Configure user settings for this site.
user_login_settings in core/modules/user/user.admin.inc
Login settings form.
user_settings_email in core/modules/user/user.admin.inc
Form builder; Configure user email settings for this site.
vertical_tabs_example_form_alter in modules/examples/vertical_tabs_example/vertical_tabs_example.module
Implements hook_form_alter().
ViewsUiBaseViewsWizard::build_form in core/modules/views_ui/wizards/views_ui_base_views_wizard.php
For AJAX callbacks to build other elements in the "show" form.
ViewsUiBaseViewsWizard::build_form_style in core/modules/views_ui/wizards/views_ui_base_views_wizard.php
Build the part of the form that builds the display format options.
views_handler_argument::options_form in core/modules/views/handlers/views_handler_argument.inc
Build the options form.
views_handler_field_bulk_form::views_form in core/modules/views/handlers/views_handler_field_bulk_form.inc
Form constructor for the bulk form.
views_handler_filter::show_build_group_button in core/modules/views/handlers/views_handler_filter.inc
Shortcut to display the build_group/hide button.
views_handler_filter::show_expose_button in core/modules/views/handlers/views_handler_filter.inc
Shortcut to display the expose/hide button.
views_handler_sort::show_expose_button in core/modules/views/handlers/views_handler_sort.inc
Shortcut to display the expose/hide button.
views_ui_add_item_form in core/modules/views_ui/views_ui.admin.inc
Form to add_item items in the views UI.
views_ui_build_preview in core/modules/views_ui/views_ui.admin.inc
views_ui_config_item_extra_form in core/modules/views_ui/views_ui.admin.inc
Form to config_item items in the views UI.
views_ui_config_item_form in core/modules/views_ui/views_ui.admin.inc
Form to config_item items in the views UI.
views_ui_config_item_group_form in core/modules/views_ui/views_ui.admin.inc
Form to config_item items in the views UI.
views_ui_config_style_form in core/modules/views_ui/views_ui.admin.inc
Form to config_style items in the views UI.
views_ui_edit_details_form in core/modules/views_ui/views_ui.admin.inc
Form builder to edit details of a view.
views_ui_edit_display_form in core/modules/views_ui/views_ui.admin.inc
Form constructor callback to configure display of a view
views_ui_edit_form in core/modules/views_ui/views_ui.admin.inc
Form builder callback for configuring a View.
views_ui_get_display_tab_details in core/modules/views_ui/views_ui.admin.inc
Helper function to get the display details section of the configure UI.
views_ui_process_container_radios in core/modules/views_ui/views_ui.admin.inc
Custom form radios process function.