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    <p>Since <code>getText()</code> is non-static you cannot call it from a static method.</p> <p>To understand why, you have to understand the difference between the two.</p> <p>Instance (non-static) methods work on objects that are of a particular type (the class). These are created with the new like this:</p> <pre><code>SomeClass myObject = new SomeClass(); </code></pre> <p>To call an instance method, you call it on the instance (<code>myObject</code>):</p> <pre><code>myObject.getText(...) </code></pre> <p><s>However a static method/field can be called <strong>only</strong> on the type directly, say like this:</s> <em>The previous statement is not correct. <a href="http://docs.oracle.com/javase/tutorial/java/javaOO/classvars.html" rel="noreferrer">One can also refer to static fields with an object reference like</a> <code>myObject.staticMethod()</code> but this is discouraged because it does not make it clear that they are class variables.</em> </p> <pre><code>... = SomeClass.final </code></pre> <p>And the two cannot work together as they operate on different data spaces (instance data and class data)</p> <p>Let me try and explain. Consider this class (psuedocode):</p> <pre><code>class Test { string somedata = "99"; string getText() { return somedata; } static string TTT = "0"; } </code></pre> <p>Now I have the following use case:</p> <pre><code>Test item1 = new Test(); item1.somedata = "200"; Test item2 = new Test(); Test.TTT = "1"; </code></pre> <p>What are the values?</p> <p>Well</p> <pre><code>in item1 TTT = 1 and somedata = 200 in item2 TTT = 1 and somedata = 99 </code></pre> <p>In other words, <code>TTT</code> is a datum that is shared by all the instances of the type. So it make no sense to say </p> <pre><code>class Test { string somedata = "99"; string getText() { return somedata; } static string TTT = getText(); // error there is is no somedata at this point } </code></pre> <p><strong>So the question is why is <em>TTT</em> static or why is getText() not static?</strong> </p> <p>Remove the <code>static</code> 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 <code>getText()</code> that require it to be non-static?</p>
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    1. USPreet Sangha
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    1. COit static because i call it from several files in my project. when i removed the "static" the error code is gone, but now i have lots of errors in other files that using this variable.
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    2. COBut that is my point. You need to understand when the two can be used.
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    3. COwhen i add the line "Constants notifications_values = new Constants(); to my main activity class, it compile OK but in the emulator it crash when this activity run
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