ایجاد پلاگینی برای پیاده سازی صفحه با قابلیت Setting API

// Add a menu for our option page
add_action('admin_menu', 'boj_myplugin_add_page');
function boj_myplugin_add_page() {
	add_options_page( 'My Plugin', 'My Plugin', 'manage_options', 'boj_myplugin', 'boj_myplugin_option_page' );
}

// Draw the option page
function boj_myplugin_option_page() {
	?>
	<div class="wrap">
		<?php screen_icon(); ?>
		<h2>My plugin</h2>
		<form action="options.php" method="post">
			<?php settings_fields('boj_myplugin_options'); ?>
			<?php do_settings_sections('boj_myplugin'); ?>
			<input name="Submit" type="submit" value="Save Changes" />
		</form>
	</div>
	<?php
}

// Register and define the settings
add_action('admin_init', 'boj_myplugin_admin_init');
function boj_myplugin_admin_init(){
	register_setting(
		'boj_myplugin_options',
		'boj_myplugin_options',
		'boj_myplugin_validate_options'
	);
	add_settings_section(
		'boj_myplugin_main',
		'My Plugin Settings',
		'boj_myplugin_section_text',
		'boj_myplugin'
	);
	add_settings_field(
		'boj_myplugin_text_string',
		'Enter text here',
		'boj_myplugin_setting_input',
		'boj_myplugin',
		'boj_myplugin_main'
	);
}

// Draw the section header
function boj_myplugin_section_text() {
	echo '<p>Enter your settings here.</p>';
}

// Display and fill the form field
function boj_myplugin_setting_input() {
	// get option 'text_string' value from the database
	$options = get_option( 'boj_myplugin_options' );
	$text_string = $options['text_string'];
	// echo the field
	echo "<input id='text_string' name='boj_myplugin_options[text_string]' type='text' value='$text_string' />";
}

// Validate user input (we want text only)
function boj_myplugin_validate_options( $input ) {
	$valid['text_string'] = preg_replace( '/[^a-zA-Z]/', '', $input['text_string'] );
	
	if( $valid['text_string'] != $input['text_string'] ) {
		add_settings_error(
			'boj_myplugin_text_string',
			'boj_myplugin_texterror',
			'Incorrect value entered!',
			'error'
		);		
	}
	
	return $valid;
}