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markwilkinson.me | @wpmark
Extensible WordPress
Plugins
WordPress Cumbria – 14th October 2014
#wpcumbria
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mark wilkinson?
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markwilkinson.me | @wpmark
father
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markwilkinson.me | @wpmark
teacher
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markwilkinson.me | @wpmark
WordPress developer
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markwilkinson.me | @wpmark
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markwilkinson.me | @wpmark
this talk will cover
what is extensibility?
why should you be making extensible plugins?
how to make your plugin extensible?
examples of good practice
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markwilkinson.me | @wpmark
this talk will cover
what is extensibility?
why should you be making extensible plugins?
how to make your plugin extensible?
examples of good practice
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markwilkinson.me | @wpmark
this talk will cover
what is extensibility?
why should you be making extensible plugins?
how to make your plugin extensible?
examples of good practice
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markwilkinson.me | @wpmark
this talk will cover
what is extensibility?
why should you be making extensible plugins?
how to make your plugin extensible?
examples of good practice
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markwilkinson.me | @wpmark
Plugin and / or Theme
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markwilkinson.me | @wpmark
Extensible Plugins
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markwilkinson.me | @wpmark
“one that can be
modified or extended
without changing the
plugin code itself ”
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markwilkinson.me | @wpmark
why?
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markwilkinson.me | @wpmark
https://www.flickr.com/photos/damndirty/10166197684
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markwilkinson.me | @wpmark
preserve future
updatability
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markwilkinson.me | @wpmark
how?
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markwilkinson.me | @wpmark
actions & filters
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markwilkinson.me | @wpmark
do_action()
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markwilkinson.me | @wpmark
do_action(
$tag,
$args
);
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markwilkinson.me | @wpmark
add_action()
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markwilkinson.me | @wpmark
add_action(
$hook,
$function,
$priority,
$accepted_args
);
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markwilkinson.me | @wpmark
example
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markwilkinson.me | @wpmark
$q = new WP_Query( $q_args );
while( $q->have_posts() ) : $->the_post();
?>
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markwilkinson.me | @wpmark
$q = new WP_Query( $q_args );
while( $q->have_posts() ) : $->the_post();
do_action( ‘wpmark_before_post’, get_the_ID() );
?>
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markwilkinson.me | @wpmark
$q = new WP_Query( $q_args );
while( $q->have_posts() ) : $->the_post();
do_action( ‘wpmark_before_post’, get_the_ID() );
?>
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markwilkinson.me | @wpmark
function wpmark_add_before_post( $post_id ) {
$meta = get_post_meta( $post_id, ‘key’, true );
/* do something with $meta */
}
add_action(
‘wpmark_before_post’,
‘wpmark_add_before_post’,
10,
1
);
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markwilkinson.me | @wpmark
apply_filters()
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markwilkinson.me | @wpmark
apply_filters(
$tag,
$value,
$var
);
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markwilkinson.me | @wpmark
add_filter()
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markwilkinson.me | @wpmark
add_filter(
$hook,
$function,
$priority,
$accepted_args
);
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markwilkinson.me | @wpmark
example
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markwilkinson.me | @wpmark
$q_args = array(
'post_type' => ’post',
'cat' => 1
);
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markwilkinson.me | @wpmark
$q_args = apply_filters(
‘wpmark_q_args’,
array(
‘post_type’ => ‘post’,
‘cat’ => 1
)
);
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markwilkinson.me | @wpmark
function wpmark_edit_q_args( $args ) {
$args[ ‘year’ ] = ‘2014’;
return $args;
}
add_filter(
‘wpmark_q_args’,
‘wpmark_edit_q_args’
10,
1
);
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markwilkinson.me | @wpmark
conclusion
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markwilkinson.me | @wpmark
when making plugins &
themes, remember to…
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markwilkinson.me | @wpmark
do_action()
&
apply_filters()
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markwilkinson.me | @wpmark
Thank you!
Questions: @wpmark (or now!)
Slides: markwilkinson.me (soon!)