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Can we instantiate an abstract class?
... are creating an instance of an anonymous subclass of your abstract class. And then you are invoking the method on your abstract class reference pointing to subclass object.
This behaviour is clearly listed in JLS - Section # 15.9.1: -
If the class instance creation expression ends in a class b...
Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?
...the other posts on tracking down the reasons for getting a SIGSEGV in an Android app. I plan to scour my app for possible NullPointers related to Canvas use, but my SIGSEGV barfs up a different memory address each time. Plus I've seen code=1 and code=2 . If the memory address was 0x00000000 ...
Placing border inside of div and not on its edge
I have a <div> element and I want to put a border on it. I know I can write style="border: 1px solid black" , but this adds 2px to either side of the div, which is not what I want.
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Xcode 4 and Core Data: How to enable SQL Debugging
I'm working on a universal iOS app and I'd like to see the raw SQL in the logs when I'm debugging. There is some info in this blog post about how to enable raw SQL logging for iOS Core Data development. The given example is for Xcode 3 and it's just not clear to me how to enable this in Xcode 4.
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Proper MIME media type for PDF files
When working with PDFs, I've run across the MIME types application/pdf and application/x-pdf among others.
3 Answers
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Resizing UITableView to fit content
I am creating an app which will have a question in a UILabel and a multiple choice answers displayed in UITableView , each row showing a multiple choice. Questions and answers will vary, so I need this UITableView to be dynamic in height.
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Why use jQuery on() instead of click()
... example coming from an AJAX call), you might want to have the same click handler that was previously bound to the same element selector, you then "delegate" the click event using on() with selector argument
To demonstrate:
http://jsfiddle.net/AJRw3/
on() can also be synonymous with click() if yo...
What's the difference between Protocol Buffers and Flatbuffers?
Both are serialization libraries and are developed by Google developers. Is there any big difference between them? Is it a lot of work to convert code using Protocol Buffers to use FlatBuffers ?
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Last non-empty cell in a column
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This works with both text and numbers and doesn't care if there are blank cells, i.e., it will return the last non-blank cell.
It needs to be array-entered, meaning that you press Ctrl-Shift-Enter after you type or paste it in. The below is for colu...
How do I check if a string contains another string in Objective-C?
...");
}
The key is noticing that rangeOfString: returns an NSRange struct, and the documentation says that it returns the struct {NSNotFound, 0} if the "haystack" does not contain the "needle".
And if you're on iOS 8 or OS X Yosemite, you can now do: (*NOTE: This WILL crash your app if this code ...