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DateTime “null” value
I've been searching a lot but couldn't find a solution. How do you deal with a DateTime that should be able to contain an uninitialized value (equivalent to null)? I have a class which might have a DateTime property value set or not. I was thinking of initializing the property holder to DateTime.Min...
How do I implement an Objective-C singleton that is compatible with ARC?
How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2?
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Rspec, Rails: how to test private methods of controllers?
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Use #instance_eval
@controller = AccountController.new
@controller.instance_eval{ current_account } # invoke the private method
@controller.instance_eval{ @current_account }.should eql ... # check the value of the instance vari...
Android: how do I check if activity is running?
Is there any simple way of determining whether or not a certain activity is active?
I want to do certain things depending on which activity is active.
eg:
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Select count(*) from multiple tables
...lect count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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Android: How to change CheckBox size?
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You just need to set the related drawables and set them in the checkbox:
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="new checkbox"
android:background="@drawable/my_checkbox_background"
android:button="...
How can I get device ID for Admob
I'm using Eclipse to develop applications for android, and I want to integrate Admob to make money.
The tutorial says I should watch the LogCat to find ID, but where is it?
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PowerShell Script to Find and Replace for all Files with a Specific Extension
I have several configuration files on Windows Server 2008 nested like such:
8 Answers
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How can I make a multipart/form-data POST request using Java?
In the days of version 3.x of Apache Commons HttpClient, making a multipart/form-data POST request was possible ( an example from 2004 ). Unfortunately this is no longer possible in version 4.0 of HttpClient .
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Can table columns with a Foreign Key be NULL?
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Yes, you can enforce the constraint only when the value is not NULL. This can be easily tested with the following example:
CREATE DATABASE t;
USE t;
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE...