Installation And Uninstallation Hooks

basic-deactivation.php

register_deactivation_hook( __FILE__, 'my_plugin_deactivation' );
function my_plugin_deactivation() {
  // Deactivation rules here
}

basic-example.php

register_activation_hook( __FILE__, 'my_plugin_activation' );
function my_plugin_activation() {
  add_option( 'my_plugin_activated', time() );
}

best-activation.php

add_action( 'init', 'my_custom_post_type' );
function my_custom_post_type() {
    $args = array(
      'public' => true,
      'label'  => 'Board Games'
    );
    register_post_type( 'boardgames', $args );
}


function myplugin_flush_rewrites() {
	my_custom_post_type();
	flush_rewrite_rules();
}

register_activation_hook( __FILE__, 'myplugin_flush_rewrites' );

create-tables.php

global $jal_db_version;
$jal_db_version = '1.0';

function jal_install() {
	global $wpdb;
	global $jal_db_version;

	$table_name = $wpdb->prefix . 'liveshoutbox';
	
	$charset_collate = $wpdb->get_charset_collate();

	$sql = "CREATE TABLE $table_name (
		id mediumint(9) NOT NULL AUTO_INCREMENT,
		time datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
		name tinytext NOT NULL,
		text text NOT NULL,
		url varchar(55) DEFAULT '' NOT NULL,
		UNIQUE KEY id (id)
	) $charset_collate;";

	require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
	dbDelta( $sql );

	add_option( 'jal_db_version', $jal_db_version );
}

function jal_install_data() {
	global $wpdb;
	
	$welcome_name = 'Mr. WordPres';
	$welcome_text = 'Congratulations, you just completed the installation!';
	
	$table_name = $wpdb->prefix . 'liveshoutbox';
	
	$wpdb->insert( 
		$table_name, 
		array( 
			'time' => current_time( 'mysql' ), 
			'name' => $welcome_name, 
			'text' => $welcome_text, 
		) 
	);
}

register_activation_hook( __FILE__, 'jal_install' );
register_activation_hook( __FILE__, 'jal_install_data' );

delete-rewrite-rules.php

register_deactivation_hook( __FILE__, 'my_plugin_deactivation' );
function my_plugin_deactivation() {
  delete_option('rewrite_rules');
}

dependency-check.php

register_activation_hook( __FILE__, 'my_plugin_activation' );

function my_plugin_activation() {
	global $wp_version;

	$php = '5.3';
	$wp  = '3.8';

	if ( version_compare( PHP_VERSION, $php, '<' ) ) {
		deactivate_plugins( basename( __FILE__ ) );
		wp_die(
			'<p>' .
			sprintf(
				__( 'This plugin can not be activated because it requires a PHP version greater than %1$s. Your PHP version can be updated by your hosting company.', 'my_plugin' ),
				$php
			)
			. '</p> <a href="' . admin_url( 'plugins.php' ) . '">' . __( 'go back', 'my_plugin' ) . '</a>'
		);
	}

	if ( version_compare( $wp_version, $wp, '<' ) ) {
		deactivate_plugins( basename( __FILE__ ) );
		wp_die(
			'<p>' .
			sprintf(
				__( 'This plugin can not be activated because it requires a WordPress version greater than %1$s. Please go to Dashboard &#9656; Updates to gran the latest version of WordPress .', 'my_plugin' ),
				$php
			)
			. '</p> <a href="' . admin_url( 'plugins.php' ) . '">' . __( 'go back', 'my_plugin' ) . '</a>'
		);
	}
}

incorrect-cpt.php

register_activation_hook( __FILE__, 'my_plugin_activation' );
function my_plugin_activation() {
  flush_rewrite_rules();
}

add_action( 'init', 'my_custom_post_type' );
function my_custom_post_type() {
    $args = array(
      'public' => true,
      'label'  => 'Board Games'
    );
    register_post_type( 'boardgames', $args );
}

incorrect-deactivation-flush.php

function myplugin_flush_rewrites_deactivate() {
	flush_rewrite_rules();
}

register_deactivation_hook( __FILE__, 'myplugin_flush_rewrites_deactivate' );

option-activation.php

register_activation_hook( __FILE__, 'my_plugin_activation' );
function my_plugin_activation() {
  add_option( 'my_plugin_activation','just-activated' );
}

add_action( 'admin_init','my_plugin_initialize' );
function my_plugin_initialize() {
    if( is_admin() && get_option( 'my_plugin_activation' ) == 'just-activated' ) {
    delete_option( 'my_plugin_activation' );
        flush_rewrite_rules();
    }
}

add_action( 'init', 'my_custom_post_type' );
function my_custom_post_type() {
    $args = array(
      'public' => true,
      'label'  => 'Board Games'
    );
    register_post_type( 'boardgames', $args );
}

security-uninstall.php

if ( ! current_user_can( 'activate_plugins' ) ) {
	return;
}
check_admin_referer( 'bulk-plugins' );

if ( __FILE__ != WP_UNINSTALL_PLUGIN ) {
	return;
}

security.php

if ( ! current_user_can( 'activate_plugins' ) ) {
	return;
}

$plugin = isset( $_REQUEST['plugin'] ) ? $_REQUEST['plugin'] : '';
check_admin_referer( "deactivate-plugin_{$plugin}" );

uninstall-hook.php

register_uninstall_hook( __FILE__, 'my_plugin_uninstall' );
function my_plugin_uninstall() {
  // Uninstallation stuff here
}

uninstall.php

if ( ! defined( 'WP_UNINSTALL_PLUGIN' ) ) {
	exit;
}

// Uninstallation actions here