Cannot make a static reference to the non-static method

Question

Building a multi-language application in Java  Getting an error when inserting String value from R string resource XML file   public static final String TTT     String  getText R string TTT     This is the error message      Error  Cannot make a static reference to the non-static method getText int  from the type         Context   How is this caused and how can I solve it

User · Answer

You can not make reference to static variable from non-static method. To understand this , you need to understand the difference between static and non-static.

Static variables are class variables , they belong to class with their only one instance , created at the first only. Non-static variables are initialized every time you create an object of the class.

Now coming to your question, when you use new() operator we will create copy of every non-static filed for every object, but it is not the case for static fields. That's why it gives compile time error if you are referencing a static variable from non-static method.

User · Answer

There are some good answers already with explanations of why the mixture of the non-static Context method getText   can t be used with your static final String   A good question to ask is   why do you want to do this   You are attempting to load a String from your strings resource  and populate its value into a public static field   I assume that this is so that some of your other classes can access it   If so  there is no need to do this   Instead pass a Context into your other classes and call context getText R string TTT  from within them   public class NonActivity        public static void doStuff Context context            String TTT   context getText R string TTT                         And to call this from your Activity   NonActivity doStuff this     This will allow you to access your String resource without needing to use a public static field

User · Answer

getText is a member of the your Activity so it must be called when  this  exists  Your static variable is initialized when your class is loaded before your Activity is created   Since you want the variable to be initialized from a Resource string then it cannot be static  If you want it to be static you can initialize it with the String value

User · Answer

You can either make your variable non static  public final String TTT     String  getText R string TTT     or make the  getText  method static  if at all possible

User · Answer

for others that find this in the search   I often get this one when I accidentally call a function using the class name rather than the object name  This typically happens because i give them too similar names   P  ie    MyClass myclass   new MyClass        then later  MyClass someFunction      This is obviously a static method   good for somethings  But what i really wanted to do  in most cases was   myclass someFunction      It s such a silly mistake  but every couple of months  i waste about 30 mins messing with vars in the  MyClass  definitions to work out what im doing wrong when really  its just a typo    Funny note  stack overflow highlights the syntax to make the mistake really obvious here

User · Answer

This question is not new and existing answers give some good theoretical background  I just want to add a more pragmatic answer    getText is a method of the Context abstract class and in order to call it  one needs an instance of it s subclass  Activity  Service  Application or other   The problem is  that the public static final variables are initialized before any instance of Context is created   There are several ways to solve this     Make the variable a member variable  field  of the Activity or other subclass of Context by removing the static modifier and placing it within the class body  Keep it static and delay the initialization to a later point  e g  in the onCreate method   Make it a local variable in the place of actual usage

User · Answer

Since getText   is non-static you cannot call it from a static method   To understand why  you have to understand the difference between the two   Instance  non-static  methods work on objects that are of a particular type  the class   These are created with the new like this   SomeClass myObject   new SomeClass      To call an instance method  you call it on the instance  myObject    myObject getText        However a static method field can be called only on the type directly  say like this  The previous statement is not correct  One can also refer to static fields with an object reference like myObject staticMethod   but this is discouraged because it does not make it clear that they are class variables          SomeClass final   And the two cannot work together as they operate on different data spaces  instance data and class data   Let me try and explain  Consider this class  psuedocode    class Test        string somedata    99        string getText     return somedata          static string TTT    0       Now I have the following use case   Test item1   new Test     item1 somedata    200     Test item2   new Test      Test TTT    1     What are the values   Well  in item1 TTT   1 and somedata   200 in item2 TTT   1 and somedata   99   In other words  TTT is a datum that is shared by all the instances of the type  So it make no sense to say   class Test            string somedata    99            string getText     return somedata       static string TTT   getText       error there is is no somedata at this point      So the question is why is TTT static or why is getText   not static    Remove the static and it should get past this error - but without understanding what your type does it s only a sticking plaster till the next error  What are the requirements of getText   that require it to be non-static

[java] Cannot make a static reference to the non-static method

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