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How to hide image broken Icon using only CSS/HTML?
...yle.display='none'"/>
or
<img src="Error.src" onerror="this.src='fallback-img.jpg'"/>
Update
You can apply this logic to multiple images at once by doing something like this:
document.addEventListener("DOMContentLoaded", function(event) {
document.querySelectorAll('img').forE...
Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
What is the difference between HashSet and List?
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Actually, I prefer the answer that points out that HashSets are suitable in cases that you can treat your collection as "bag items". Set operations are not so frequent as Containment checks. At any point that you have a set of un...
What is the difference between pluck and collect in Rails?
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When you do:
User.first.gifts.collect(&:id)
You have objects with all fields loaded and you simply get the id thanks to the method based on Enumerable.
So:
if you only need the id with Rails 4, use ids: User.first.gifts.ids
if you only need some fields with Rails 4, use pluck: User.first...
Why does DEBUG=False setting make my django Static Files Access fail?
Am building an app using Django as my workhorse. All has been well so far - specified db settings, configured static directories, urls, views etc. But trouble started sneaking in the moment I wanted to render my own beautiful and custom 404.html and 500.html pages.
...
configure: error: C compiler cannot create executables
...be left over from migrating from an older version of the OS. If you've installed Xcode 4.3.x, you need to launch it, go into its preferences, select the Downloads tab, and click "Install" next to the Command Line Tools package.
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CSS3 gradient background set on body doesn't stretch but instead repeats?
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I know I'm late to the party, but here's a more solid answer.
All you need to do is use min-height: 100%; rather than height: 100%; and your gradient background will extend the entire height of the viewport without repeating, even if the content is scrollable.
Like this:
html {
mi...
Android View.getDrawingCache returns null, only null
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sorry, personally, can't help you with your question :'( -> nice that it worked :)
– cV2
Jul 26 '13 at 11:36
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Change a Git remote HEAD to point to something besides master
...-f origin master
Making master have what you want people to use, and do all other work in branches.
(a "git-symbolic-ref HEAD refs/head/published" would not be propagated to the remote repo)
This is similar to "How do I delete origin/master in Git".
As said in this thread: (emphasis mine)
"git...
HorizontalScrollView within ScrollView Touch Handling
...talScrollView block that has features that can be scrolled through horizontally. I've added an ontouchlistener to the horizontalscrollview to handle touch events and force the view to "snap" to the closest image on the ACTION_UP event.
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