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NULL vs nil in Objective-C
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nil should only be used in place of an id, what we Java and C++ programmers would think of as a pointer to an object. Use NULL for non-object pointers.
Look at the declaration of that method:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object...
What should my Objective-C singleton look like? [closed]
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Another option is to use the +(void)initialize method. From the documentation:
The runtime sends initialize to each class in a program exactly one time just before the class, or any class that inherits from it, is sent its first message from within the ...
What is SELF JOIN and when would you use it? [duplicate]
...e references data in itself.
E.g., an Employee table may have a SupervisorID column that points to the employee that is the boss of the current employee.
To query the data and get information for both people in one row, you could self join like this:
select e1.EmployeeID,
e1.FirstName,
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What is a mixin, and why are they useful?
...rator
then the class gets an __iter__ mixin method for free.
Therefore at least on this point of the documentation, mixin does not not require multiple inheritance, and is coherent with Definition 1.
The documentation could of course be contradictory at different points, and other important Python ...
Android: Is it possible to display video thumbnails?
I created a video recording application with library dialog. The library dialog displays the list of recorded videos where each item consists of icon, video title, tags and location information the following way:
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How to check if an array value exists?
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Is it possible to have an array with identical keys? Wouldn't the second value overwrite the original?
– Citricguy
Jun 9 '12 at 1:51
add...
Migration: Cannot add foreign key constraint
...ma::create('priorities', function($table) {
$table->increments('id', true);
$table->integer('user_id')->unsigned();
$table->string('priority_name');
$table->smallInteger('rank');
$table->text('class');
$table->timestamps('timecreat...
Best way to get identity of inserted row?
What is the best way to get IDENTITY of inserted row?
14 Answers
14
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Inserting HTML into a div
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I think this is what you want:
document.getElementById('tag-id').innerHTML = '<ol><li>html data</li></ol>';
Keep in mind that innerHTML is not accessable for all types of tags when using IE. (table elements for example)
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Android draw a Horizontal line between views
...ray colored Line between TextView & ListView
<TextView
android:id="@+id/textView1"
style="@style/behindMenuItemLabel1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="1dp"
android:text="FaceBook Feeds" />
<V...