Magento 2 theme giving error Unable to load theme by specified key: 'Yogesh/mytheme'

Question

I have try to create custom theme I have got following error.

Unable to load theme by specified key: 'Yogesh/mytheme'

Below is my folder structure.

\magento2\app\design\frontend\Yogesh\mytheme

• media
  • preview.jpg
• composer.json
• registration.php
• theme.xml

Following are content of files.

Composer.json

{
    "name": "magento/theme-frontend-blank",
    "description": "N/A",
    "require": {
        "php": "~5.5.0|~5.6.0|~7.0.0",
        "magento/theme-frontend-blank": "100.0.*",
        "magento/framework": "100.0.*"
    },
    "type": "magento2-theme",
    "version": "100.0.1",
    "license": [
        "OSL-3.0",
        "AFL-3.0"
    ],
    "autoload": {
        "files": [
            "registration.php"
        ]
    }
}

registration.php

\Magento\Framework\Component\ComponentRegistrar::register(
\Magento\Framework\Component\ComponentRegistrar::THEME,
'frontend/Yogesh/mytheme',
__DIR__
);

theme.xml

<theme xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Config/etc/theme.xsd">
 <title>Yogesh mytheme</title> 
 <parent>Magento/blank</parent>
 <media>
     <preview_image>media/preview.jpg</preview_image> 
 </media>

I have try with php bin/magento setup:upgrade but my module is not registered, not showing in config.php.

After I have try to setup:static-content:deploy but my theme content not deployed.

My theme is not able to load what mistake I have doing?

Answer 1

1. Try clear the cache and run the bin/magento setup:static-content:deploy again.
2. To add new theme you need to turn in developer mode.
3. Sometimes new theme added to theme table in our database with param type=1 (virtual theme). Try to set it to 0 (physical theme). For example:

mysql> insert into theme
(parent_id,theme_path,theme_title,preview_image,is_featured,area,type,code) VALUES ('1','MyVendor/Base','MyVendor Base', NULL, 0, 'frontend', 0, 'MyVendor/Base');

We can read more here:

https://github.com/magento/magento2/issues/3409 https://github.com/magento/magento2/issues/2797

Answer 2

Please check cms_page table in database and check if Yogesh/mytheme is set in custom_theme column then execute this query in phpmyadmin,

UPDATE `cms_page` SET `custom_theme` = NULL WHERE `custom_theme` IS NOT NULL

In my case, I found records in the cms_page table referring to a non-existent theme.

This is work for me properly. I hope this will help you.

Answer 3

There is a great change there is still a reference to this theme, I had the same problem. These were the steps I took to solve the problem:

1. I went to the table theme to see what the original theme_id of the deleted theme was.
2. I checked several tables for the occurence of this theme_id. Tables I checked: cms_page, layout_link, design_config_grid_flat, core_config_data.
3. You can check if the ids are correct, using the following SQL:

SELECT * FROM core_config_data WHERE path LIKE '%theme%';

4. Change all these theme ids to the correct ids. Preferably via an upgrade script.

I used the following:

    $setup->run("
        DELETE FROM theme WHERE `theme_path` LIKE 'Vendor/module';
    ");

    $setup->run("
        UPDATE cms_page SET `custom_theme` = NULL WHERE `custom_theme` IS NOT NULL
    ");

    $setup->run("
        UPDATE design_config_grid_flat SET `theme_theme_id` = 6 WHERE `theme_theme_id` = 4
    ");

    $setup->run("
        UPDATE core_config_data SET `value` = 6 WHERE `path` = 'design/theme/theme_id' AND `value` = 4
    ");

I hope this helps, it's merely a collection of different solutions I found, plus my own interpretation!

Answer 4

After trying all other answers here (to no avail) the following order of commands helped (in developer mode):

rm -r pub/static/* var/view_preprocessed/* var/cache/* var/di var/generation
bin/magento cache:clean
bin/magento cache:flush
bin/magento setup:upgrade
bin/magento setup:di:compile
bin/magento setup:static-content:deploy de_DE en_US

Answer 5

You have to some error in your composer.json file,

{
    "name": "Yogesh/theme-frontend-mytheme",
    "description": "N/A",
    "require": {
        "php": "~5.5.0|~5.6.0|~7.0.0",
        "magento/theme-frontend-blank": "100.0.*",
        "magento/framework": "100.0.*"
    },
    "type": "magento2-theme",
    "version": "100.0.1",
    "license": [
        "OSL-3.0",
        "AFL-3.0"
    ],
    "autoload": {
        "files": [
            "registration.php"
        ]
    }
}

After set Composer file, You have to set your theme from Stores -> Configuration -> Design.

Now run command,

php bin/magento setup:upgrade

php bin/magento setup:static-content:deploy

Remove var folder and check again.

Answer 6

Need log. See bugs Magento 2 : https://github.com/magento/magento2/issues/2547 Ans. AlanKent