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ViewPager and fragments — what's the right way to store fragment's state?
...agment will be placed. FragmentPagerAdapter.getItem(int position) is only called when a fragment for that position does not exist. After rotating, Android will notice that it already created/saved a fragment for this particular position and so it simply tries to reconnect with it with FragmentManage...
How do I give text or an image a transparent background using CSS?
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The first hex number defines the alpha value of the color.
Full solution all browsers:
.alpha60 {
/* Fallback for web browsers that doesn't support RGBa */
background: rgb(0, 0, 0) transparent;
/* RGBa with 0.6 opacity */
background: rgba(0, 0, 0, 0.6);
/* For IE 5.5 - 7*/
...
Why exactly is eval evil?
I know that Lisp and Scheme programmers usually say that eval should be avoided unless strictly necessary. I’ve seen the same recommendation for several programming languages, but I’ve not yet seen a list of clear arguments against the use of eval . Where can I find an account of the potentia...
Importing Maven project into Eclipse
...ot really usable ~2 years ago, see the feedback in Mevenide vs. M2Eclipse, Q for Eclipse/IAM). But, even if I do not use things like creating a Maven project from Eclipse or the POM editor or other fancy wizards, I have to say that this plugin is now totally usable, provides very smooth integration,...
What's wrong with nullable columns in composite primary keys?
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Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonally, NULL is al...
Understanding checked vs unchecked exceptions in Java
.... these that you should explicitly catch or rethrow) should not be used at all. They were eliminated in C# for example, and most languages don't have them. So you can always throw a subclass of RuntimeException (unchecked exception)
However, I think checked exceptions are useful - they are used whe...
Plot two graphs in same plot in R
...object with basic aesthetics and enhance it incrementally.
ggplot style requires data to be packed in data.frame.
# Data generation
x <- seq(-2, 2, 0.05)
y1 <- pnorm(x)
y2 <- pnorm(x,1,1)
df <- data.frame(x,y1,y2)
Basic solution:
require(ggplot2)
ggplot(df, aes(x)) + ...
Will docker container auto sync time with the host machine?
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I don't know if the original question was more about timezones (e.g. making sure that the container will honor DST and timezone changes) or accurate time keeping (e.g. making sure that the container clock will not drift). If it's about timezones, that an...
NSLog the method name with Objective-C in iPhone
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To technically answer your question, you want:
NSLog(@"<%@:%@:%d>", NSStringFromClass([self class]), NSStringFromSelector(_cmd), __LINE__);
Or you could also do:
NSLog(@"%s", __PRETTY_FUNCTION__);
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Performance surprise with “as” and nullable types
...lable types, and I'm adding a section about using the "as" operator, which allows you to write:
10 Answers
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