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Javascript - How to detect if document has loaded (IE 7/Firefox 3)
I want to call a function after a document loads, but the document may or may not have finished loading yet. If it did load, then I can just call the function. If it did NOT load, then I can attach an event listener. I can't add an eventlistener after onload has already fired since it won't get cal...
Choose between ExecutorService's submit and ExecutorService's execute
...ng the task to be invoked. The default UncaughtExceptionHandler, which typically prints the Throwable stack trace to System.err, will be invoked if no custom handler has been installed.
On the other hand, a Throwable generated by a task queued with submit() will bind the Throwable to the Future tha...
How to Update Multiple Array Elements in mongodb
...atory setting of .updateMany() in modern API versions.
NOTE Somewhat ironically, since this is specified in the "options" argument for .update() and like methods, the syntax is generally compatible with all recent release driver versions.
However this is not true of the mongo shell, since the way t...
Show hide fragment in android
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Fragment is a child of Object and not View so one cannot call: fragment.setVisibility(View.INVISIBLE);
– AndroidGeek
Jul 16 '14 at 9:53
8
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What's “this” in JavaScript onclick?
... to the element containing the action. For example, if you have a function called hide():
function hide(element){
element.style.display = 'none';
}
Calling hide with this will hide the element. It returns only the element clicked, even if it is similar to other elements in the DOM.
For exampl...
When should I use UNSIGNED and SIGNED INT in MySQL?
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Basically with UNSIGNED, you're giving yourself twice as much space for the integer since you explicitly specify you don't need negative numbers (usually because values you store will never be negative).
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On showing dialog i get “Can not perform this action after onSaveInstanceState”
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it's better to call super.show(manager, tag) inside try-catch clause. The flags owned by DialogFragment can stay safe this way
– Shayan_Aryan
Jan 16 '17 at 10:33
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What issues should be considered when overriding equals and hashCode in Java?
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The theory (for the language lawyers and the mathematically inclined):
equals() (javadoc) must define an equivalence relation (it must be reflexive, symmetric, and transitive). In addition, it must be consistent (if the objects are not modified, then it must keep returning the ...
How to create a protocol with methods that are optional?
...u must check whether an object implements that method before attempting to call it.
As an example, the pie chart view might test for the segment title method like this:
NSString *thisSegmentTitle;
if ([self.dataSource respondsToSelector:@selector(titleForSegmentAtIndex:)]) {
thisSegmentTitle =...
How do you track record relations in NoSQL?
...hat redundant sets of data will get out of sync with one another. This is called an anomaly. When you use a normalized relational database, the RDBMS can prevent anomalies. In a denormalized database or in NoSQL, it becomes your responsibility to write application code to prevent anomalies.
One ...