Upload and Enable the Modules
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Go to Administer >> Site Building >> Modules >> check all 5 Devel boxes and click "Save configuration".
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Go to the front of your site and look in the bottom-left hand corner. You'll see a black box called "Themer Info". Check that box.
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Up in the top-right corner of the site you'll see a larger black box. It does a pretty good job of explaining what to to!
Examine Your Site
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Hover over any part of your site and you'll see a red box around that particular element.
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1) Template called: the name of the file which is controlling the layout of this element
2) FIle used: the location of the file in #1
3) Candidate template files: if you'd like to create an override for this part of the page, these are suggested file names. The easiest thing to do is copy the file in #2, renaming it and saving it in your template folder. This is what the files mentioned in this example would do:
- block-user-1.tpl.php ... if you create this file, it will only provide a template for this particular block
- block-user.tpl.php ... if you create this file, it will only provide a template for this user blocks
- block-left.tpl.php ... if you create this file, it will only provide a template for blocks in the left div.
- block.tpl.php ...if you create this file, it will provide a template for all blocks
4) Preprocess functions: These functions connect what happens in the module code to what gets sent to the theme