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My theme currently has the following line in the function.php file: if ( $_GET['activated'] == 'true' || $_GET['preview'] == 1 ) If this statement is true the code runs a function.

I am getting a php error that says Notice: Undefined index: activated in and Notice: Undefined index: preview in.

I am sure in wordrpess there is another way to do this "if statement" to prevent the Undefined index: error I am getting.

Any suggestions?

Thank you!

Here is the full code:


add_action('admin_menu', 'ddthemes_admin');


 if ( $_GET['activated'] == 'true'  || $_GET['preview'] == 1 )

{ ddthemes_setup(); } function ddthemes_admin() { /* PROCESS OPTION SAVING HERE */ if ( 'save' == $_REQUEST['action'] ) { if ( $_REQUEST['savetype'] == 'header' ) { update_option( 'ddthemes_header', $_REQUEST['ddthemes_header']); } } /* SHOW THEME CUSTOMIZE PAGE HERE */

add_theme_page(__('Logo Options'), __('Logo Options'), 'edit_themes', basename(__FILE__), 'ddthemes_headeropt_page');}

share|improve this question
up vote 1 down vote accepted


if ( isset($_GET['activated']) && $_GET['activated'] == 'true' || isset($_GET['preview']) && $_GET['preview'] == 1 )

instead of

if ( $_GET['activated'] == 'true' || $_GET['preview'] == 1 )


You should wrap the if-sentence in the functions.php file into a function and a relevant hook. Here is an example using the after_theme_setup hook:

function my_theme_setup(){
    if ( isset($_GET['activated']) && $_GET['activated'] == 'true' || isset($_GET['preview']) && $_GET['preview'] == 1 ){
share|improve this answer
Thank your for the reply. I used your code and got this error Warning: Cannot modify header information - headers already sent by (output started at /home3/an/public_html/wp-content/themes/tipztheme/functions.php:1) in /home3/answerun/public_html/wp-includes/pluggable.php on line 876 I updated the full code above, perhaps that is causing the error with isset. Any ideas? – user1609391 Feb 15 '13 at 23:09
the if-code you are using is not within a function and most likely ddthemes_setup() is printing out some stuff. you should consider to hook it into init or some relevant hook. – birgire Feb 15 '13 at 23:23
it looks like the hook after_setup_theme could be relevant - I updated the code example above. – birgire Feb 15 '13 at 23:35
thank you so much. That worked to solve the issue. One minor error in your code { at opening of the if statement. Thank you again! – user1609391 Feb 16 '13 at 0:45
ok great, I updated the code with the missing { - thanks – birgire Feb 16 '13 at 0:58

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