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How to center a (background) image within a div?

... If you want the entire div to be filled with the image and no extra space you should use background-size: cover; If you want the entire image to show without any part of the image being cut off or stretched you want to use background-size: contain; – Zlerp ...
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Rails where condition using NOT NIL

...S NOT NULL Note that this syntax reports a deprecation (it talks about a string SQL snippet, but I guess the hash condition is changed to string in the parser?), so be sure to add the references to the end: Foo.includes(:bar).where.not(bars: {id: nil}).references(:bar) DEPRECATION WARNING: I...
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How to set commands output as a variable in a batch file

...SET var=%%F ) ECHO %var% I always use the USEBACKQ so that if you have a string to insert or a long file name, you can use your double quotes without screwing up the command. Now if your output will contain multiple lines, you can do this SETLOCAL ENABLEDELAYEDEXPANSION SET count=1 FOR /F "token...
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How do I enable standard copy paste for a TextView in Android?

... cManager.setPrimaryClip(cData); Util.toast(mContext, string.text_copyed); return true; } }); share | improve this answer | ...
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Finding Key associated with max Value in a Java Map

...s with maximum value public class NewClass4 { public static void main(String[] args) { HashMap<Integer,Integer>map=new HashMap<Integer, Integer>(); map.put(1, 50); map.put(2, 60); map.put(3, 30); map.put(4, 60); map.put(5, 60); ...
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Why do we need extern “C”{ #include } in C++?

..._gxx_personality_v0 The foo function is actually called "_Z3foov". This string contains type information for the return type and parameters, among other things. If you instead write test.C like this: extern "C" { void foo() { } } Then compile and look at symbols: $ g++ -c test.C $ nm tes...
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What is “the inverse side of the association” in a bidirectional JPA OneToMany/ManyToOne association

...e = 1) private Integer id; @Column(name = "BOY_NAME") private String name; @OneToOne(cascade = { CascadeType.ALL }) private GirlFriend21 girlFriend; public BoyFriend21(String name) { this.name = name; } public BoyFriend21() { } public Integer getI...
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find() with nil when there are no records

...ou already have a block such as a controller method. In that case the only extra line you need is the rescue line. Much more elegant and easier to handle than checking for nil with an if statement. – morgler Aug 1 '17 at 7:30 ...
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How to pass command line arguments to a rake task

... Also, make sure you enclose the argument in string. e.g from your command line run the rake task like so rake thing:work'[1,2,3]' – theterminalguy Jan 14 '17 at 8:01 ...
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Way to get number of digits in an int?

... Your String-based solution is perfectly OK, there is nothing "un-neat" about it. You have to realize that mathematically, numbers don't have a length, nor do they have digits. Length and digits are both properties of a physical re...