Can not unset rows of a view programmatically

Question

I created a view of terms using views_tree module. I need to remove some of the terms under some conditions. This is my code

function THEME_views_pre_render(&$views) {
    for($i = 0 ; $i < sizeof($views->result) ; $i++)
       unset($views->result[$i]);
}

But it still prints all of the terms and doesn't delete any of them. I tried this code

function THEME_views_pre_render(&$views) {
    for($i = 0 ; $i < sizeof($views->result) ; $i++){
        $views->result[$i]->taxonomy_term_data_name ="Hello";
    }
}

It successfully renamed every term, But when I tried the following code, every name turned back to what it was from the beginning and nothing removed.

function THEME_views_pre_render(&$views) {
    for($i = 0 ; $i < sizeof($views->result) ; $i++){
        $views->result[$i]->taxonomy_term_data_name ="Hello";
        unset($views->result[$i]);
    }
}

How can I remove some terms ?

Answer 1

It should work on template.php too. Module implementation does not look mandatory here. I have noticed a few issues in the code sample that you have pasted.

1. There is a typo. It should be $view not $views.

2. Instead of

   for($i = 0 ; $i < sizeof($view->result) ; $i++){
   }
   

   Do

   $sizeof_result = sizeof($view->result);
   for($i = 0 ; $i < $sizeof_result ; $i++)
   

The following code works for me:

function MYTHEME_views_pre_render(&$view){
  if($view->name == 'MY_VIEW'){
    $sizeof_result = sizeof($view->result);
    for($i = 0 ; $i < $sizeof_result ; $i++){
      //IF Condition
        unset($view->result[$i]);
    } 
  }
}

The reason for using variable $sizeof_result instead of sizeof($view->result) in for loop is:

For each execution of the loop, the value of sizeof($view->result) changes(decreases by 1). Due to this, the for loops does not work as expected.

Answer 2

Use basically the same code in THEME_views_post_execute(&$view) https://api.drupal.org/api/views/views.api.php/function/hook_views_post_execute/7.x-3.x

Answer 3

As jackrabbithanna said, maybe implementation of the code in a module may resolve your problem, I also had excluded some view results in a project using an auxiliary result set as code below , hope that helps:

/**
  * Implementation of hook_views_pre_render().
  */
function MYMODULE_views_pre_render(&$view) {
  $new_result = [];
  foreach ($view->result as $key => $value) {
   if(SHOULD NOT EXCLUDED)
    $new_result[] = $value;
  }
  $view->result = $new_result;
}