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How to lay out Views in RelativeLayout programmatically?
I'm trying to achieve the following programmatically (rather than declaratively via XML):
9 Answers
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Prevent segue in prepareForSegue method?
...hen return YES; if it's not then return NO; and the prepareForSegue is not called.
Note that this method doesn't get called automatically when triggering segues programmatically. If you need to perform the check, then you have to call shouldPerformSegueWithIdentifier to determine whether to perform...
How do you debug MySQL stored procedures?
...t process for debugging stored procedures is very simple. I create a table called "debug" where I insert variable values from the stored procedure as it runs. This allows me to see the value of any variable at a given point in the script, but is there a better way to debug MySQL stored procedures?
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What's the difference between event.stopPropagation and event.preventDefault?
...t;/div>
With stopPropagation, only the button's click handler is called while the div's click handler never fires.
Where as if you use preventDefault, only the browser's default action is stopped but the div's click handler still fires.
Below are some docs on the DOM event properties and...
How to update a menu item shown in the ActionBar?
...for the affected MenuItem. It is possible that showAsAction simply automatically creates action views for you. If so, you can presumably enable/disable that View.
I can't seem to find a way to get the currently set Menu to manipulate it except for in onPrepareOptionMenu.
You can hang onto the ...
Problems with contenttypes when loading a fixture in Django
...will use a more durable representation of foreign keys. In django they are called "natural keys". For example:
Permission.codename is used in favour of Permission.id
User.username is used in favour of User.id
Read more: natural keys section in "serializing django objects"
Some other useful argu...
Rails :include vs. :joins
...ns will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all the included tables attributes. If you call associa...
HTML.ActionLink method
...h are none. You need this value
// otherwise you call the WRONG method ...
// (refer to comments, below).
)
This uses the following method ActionLink signature:
public static string ActionLink(this HtmlHelper htmlHelper,
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How to read an external local JSON file in JavaScript?
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You cannot make a AJAX call to a local resource as the request is made using HTTP.
A workaround is to run a local webserver, serve up the file and make the AJAX call to localhost.
In terms of helping you write code to read JSON, you should read t...
Rails Object to hash
...nly attributes, then you can get them by:
@post.attributes
Note that this calls ActiveModel::AttributeSet.to_hash every time you invoke it, so if you need to access the hash multiple times you should cache it in a local variable:
attribs = @post.attributes
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