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Android Camera : data intent returns null
I have an android application which contains multiple activities.
11 Answers
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Running multiple AsyncTasks at the same time — not possible?
I'm trying to run two AsyncTasks at the same time. (Platform is Android 1.5, HTC Hero.)
However, only the first gets executed. Here's a simple snippet to describe my problem:
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When to use AtomicReference in Java?
...e = someFunctionOfOld(cachedValueToUpdate);
boolean success = cache.compareAndSet(cachedValue,cachedValueToUpdate);
Because of the atomic reference semantics, you can do this even if the cache object is shared amongst threads, without using synchronized. In general, you're better off using synchro...
Securely storing environment variables in GAE with app.yaml
I need to store API keys and other sensitive information in app.yaml as environment variables for deployment on GAE. The issue with this is that if I push app.yaml to GitHub, this information becomes public (not good). I don't want to store the info in a datastore as it does not suit the project...
select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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What's the best way to send a signal to all members of a process group?
...se if the tree is the result of forking from a server start or a shell command line.) You can discover process groups using GNU ps as follows:
ps x -o "%p %r %y %x %c "
If it is a process group you want to kill, just use the kill(1) command but instead of giving it a process number, give it th...
List files by last edited date
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You can use:
ls -Rt
where -R means recursive (include subdirectories) and -t means "sort by last modification date".
To see a list of files sorted by date modified, use:
ls -l -Rt
An alias can also be created to achieve this:
alias lt='ls -lht'
lt
Where -h gives a more readable output....
AES Encryption for an NSString on the iPhone
...ethod which takes two NSString instances, one being the message to encrypt and the other being a 'passcode' to encrypt it with - I suspect I'd have to generate the encryption key with the passcode, in a way that can be reversed if the passcode is supplied with the encrypted data. The method should t...
Why malloc+memset is slower than calloc?
...se it can skip memset() entirely. In other cases, calloc() can even cheat and not allocate any memory! However, malloc()+memset() will always do the full amount of work.
Understanding this requires a short tour of the memory system.
Quick tour of memory
There are four main parts here: your prog...
How can I obtain the element-wise logical NOT of a pandas Series?
I have a pandas Series object containing boolean values. How can I get a series containing the logical NOT of each value?
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