I tired of the fact that many users forget to specify the category when add news in my site. Therefore I made to the code a couple of extra lines to remind the user of the need to specify a category.
Do IT
Open file engine/modules/addnews.php
Find
        if( $config['allow_site_wysiwyg'] == "yes" ) $script .= "<form method=post name=\"entryform\" id=\"entryform\" onsubmit=\"document.getElementById('short_story').value = tinyMCE.get('short_story').getContent(); document.getElementById('full_story').value = tinyMCE.get('full_story').getContent(); if(document.entryform.title.value == '' || document.entryform.short_story.value == ''){alert('$lang[add_err_7]');return false}\" action=\"\">";
        else $script .= "<form method=post name=\"entryform\" id=\"entryform\" onsubmit=\"if(document.entryform.title.value == '' || document.entryform.short_story.value == ''){alert('$lang[add_err_7]');return false}\" action=\"\">";
Replace to
        $spe_category = ";if(document.entryform.category.value == '') { alert('Vui long chon chuyen muc cua bai viet');;return false } ";
        if( $config['allow_site_wysiwyg'] == "yes" ) $script .= "<form method=post name=\"entryform\" id=\"entryform\" onsubmit=\"document.getElementById('short_story').value = tinyMCE.get('short_story').getContent(); document.getElementById('full_story').value = tinyMCE.get('full_story').getContent(); if(document.entryform.title.value == '' || document.entryform.short_story.value == ''){alert('$lang[add_err_7]');return false}$spe_category\" action=\"\">";
        else $script .= "<form method=post name=\"entryform\" id=\"entryform\" onsubmit=\"if(document.entryform.title.value == '' || document.entryform.short_story.value == ''){alert('$lang[add_err_7]');return false}$spe_category\" action=\"\">";       Â
----------------------------------------------------
If you want to apply this h@ck in Admin CP, follow steps below
Open file engine/inc/addnews.php
----------------------------------------------------
Find
    if( $config['allow_admin_wysiwyg'] == "yes" ) echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"document.getElementById('short_story').value = tinyMCE.get('short_story').getContent(); document.getElementById('full_story').value = tinyMCE.get('full_story').getContent(); if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}\" action=\"$PHP_SELF\">";
    else echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}\" action=\"$PHP_SELF\">";
    else echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}\" action=\"$PHP_SELF\">";
Replace to
$spe_category = ";if(document.addnews.category.value == '') { alert('Please choose at least a category');;return false } ";
    if( $config['allow_admin_wysiwyg'] == "yes" ) echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"document.getElementById('short_story').value = tinyMCE.get('short_story').getContent(); document.getElementById('full_story').value = tinyMCE.get('full_story').getContent(); if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}$spe_category\" action=\"$PHP_SELF\">";
    else echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}$spe_category\" action=\"$PHP_SELF\">";
    if( $config['allow_admin_wysiwyg'] == "yes" ) echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"document.getElementById('short_story').value = tinyMCE.get('short_story').getContent(); document.getElementById('full_story').value = tinyMCE.get('full_story').getContent(); if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}$spe_category\" action=\"$PHP_SELF\">";
    else echo "<form method=post name=\"addnews\" id=\"addnews\" onsubmit=\"if(document.addnews.title.value == '' || document.addnews.short_story.value == ''){alert('$lang[addnews_alert]');return false}$spe_category\" action=\"$PHP_SELF\">";
Source : dleviet.com
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