MVC what stage sets a task if none provided

Question

I am trying to understand Joomla's MVC logic. please help me figure out the processing of the task

Unedited code from a Joomla package has the front end article edit form with the task field, but its value is missing (file root/components/com_content/views/form/tmpl/edit.php ):

<input type="hidden" name="task" value="" />

By default, the URL of the form's action does not have a task parameter. This is how I see the URL for the action:

JRoute::_('index.php?option=com_content&a_id=' . (int) $this->item->id); ?>

I am not sure, but I think that when the flow reaches the component's entry point, in this case, file root/components/com_content/content.php, the input includes a task article.save

The input data I get is:

 ["data":protected]=>
  &array(13) {
    ["a_id"]=>
    string(1) "7"
    ["jform"]=>
    array(12) {
      ["title"]=>
      string(69) "Test 1"
      ["version_note"]=>
      string(0) ""
      ["state"]=>
      string(1) "1"
      ["publish_up"]=>
      string(19) "2018-05-23 05:37:29"
      ["publish_down"]=>
      string(0) ""
      ["tags"]=>
      array(3) {
        [0]=>
        string(1) "2"
        [1]=>
        string(1) "4"
        [2]=>
        string(1) "6"
      }
      ["metadesc"]=>
      string(0) ""
      ["metakey"]=>
      string(0) ""
      ["articletext"]=>
      string(181) "<p>TEST This is some text</p>
<p>Line 1</p>
<p>Line 2</p>
<p> </p>
<p>Line 3</p>
<p> </p>
<p>Line 7</p>"
      ["com_fields"]=>
      array(1) {
        ["testfield"]=>
        string(27) "<span class="star">@</span>"
      }
      ["catid"]=>
      string(1) "8"
      ["language"]=>
      string(1) "*"
    }
    ["task"]=>
    string(12) "article.save"
    ["return"]=>
    string(180) "aW5kZXgucGhwP29wdGlvbj1jb21fY29udGVudCZ0YXNrPWFydGljbGUuZWRpdCZhX2lkPTcmcmV0dXJuPWFIUjBjSE02THk5c2IyTmhiR2h2YzNRdmMyaHZjblJ6ZEc5eWVTNXpjR0ZqWlM5d2RXSnNhV05mYUhSdGJDOTBaWE4wTFRFPQ=="
    ["13456789"]=>
    string(1) "1"
    ["option"]=>
    string(11) "com_content"
    ["view"]=>
    string(8) "category"
    ["layout"]=>
    string(4) "blog"
    ["id"]=>
    string(1) "8"
    ["Itemid"]=>
    string(3) "101"
  }

Where is the task set?

Given the original edit.php file is missing a value for the task field, is there another field in this form that influences the setting of the task in a file that is called after I click the save button?

Like I try to communicate above, the component's input shows ["task"]=>string(12) "article.save" when the component's entry point file is called (i.e., root/components/com_content/content.php"

Given that the URL task parameter is missing from the form's action, does the URL from which I make the request influences the code that sets the task?

I welcome any information in helping to understand Joomla's MVC logic

Answer 1

If you inspect the button in the back end, you'll notice that for the most part they are <button onclick="Joomla.submitbutton('view.task');"></button>. When Joomla.submitbutton is called, the value passed into it is automatically transferred into <input type="hidden" name="task" /> if found inside of a <form> with the ID adminForm.

Otherwise, controllers automatically default all tasks to view.display if no task is given.