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Do the parentheses after the type name make a difference with new?
...erated as opposed to user-defined.
new C - default-initializes C, which calls the default ctor.
new C() - value-initializes C, which calls the default ctor.
So in all versions of C++ there's a difference between new A and new A() because A is a POD.
And there's a difference in behavior betwee...
onMeasure custom view explanation
...als, but each one is a little bit different than the other. Sometimes they call super.onMeasure at the end, sometimes they use setMeasuredDimension and didn't call it. Where is a difference?
...
What is the purpose of a stack? Why do we need it?
...rs like the C# compiler generate CIL, and then at runtime another compiler called the JIT (Just In Time) compiler turns the IL into actual machine code that can execute.
So first let's answer the question "why have MSIL at all?" Why not just have the C# compiler write out machine code?
Because i...
Repeat table headers in print mode
Is it possible in CSS using a property inside an @page to say that table headers (th) should be repeated on every page if the table spreads over multiple pages?
...
What is the use of static constructors?
... required configuration data into readonly fields, etc.
It is run automatically by the runtime the first time it is needed (the exact rules there are complicated (see "beforefieldinit"), and changed subtly between CLR2 and CLR4). Unless you abuse reflection, it is guaranteed to run at most once (ev...
Understanding __get__ and __set__ and Python descriptors
...ith the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would ...
How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?
20...
JavaScript % (modulo) gives a negative result for negative numbers
...
I don't know that I would call it a "bug". The modulo operation is not very well defined over negative numbers, and different computing environments handle it differently. Wikipedia's article on the modulo operation covers it pretty well.
...
Update ViewPager dynamically?
... solution is to override getItemPosition(). When notifyDataSetChanged() is called, ViewPager calls getItemPosition() on all the items in its adapter to see whether they need to be moved to a different position or removed.
By default, getItemPosition() returns POSITION_UNCHANGED, which means, "This...
Finish an activity from another activity
...ingleInstance"
When the user clicks new, do FirstActivity.fa.finish(); and call the new Intent.
When the user clicks modify, call the new Intent or simply finish activity B.
FIRST WAY
In your first activity, declare one Activity object like this,
public static Activity fa;
onCreate()
{
fa = ...