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POAndroid Null Checker
 

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  1. POAndroid Null Checker
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    <p>I have a program that relates to a database. I start out my program by inserting a row using the following command.</p> <pre><code> long id = db.insertMajor(null, null, null, null); </code></pre> <p>it works perfect. I than alter the information but lets ignore that since for the time being I commented out all those lines. Now I want to check and see if it is null which is should be. If it is not null than I would like to check a checkbox. if it is null than I want to leave the box unchecked. So far I have this line to test.</p> <pre><code> String change = db.getMajorTitle(value).getString(1); if (change.equals(null)) { filled = false; } </code></pre> <p>the filled boolean will check the box or not. If the database field is filled or not I always get a checkmark. Whats wrong?</p> <p>UPDATE: Since no one has figure it out I will post most of my code to try and help figure it out. I have also reset my emulator to ensure there is not problems with corrupted data.</p> <pre><code> chk1.setChecked(checker(1)); chk2.setChecked(checker(2)); chk3.setChecked(checker(3)); chk4.setChecked(checker(4)); } boolean checker(int value){ DBAdapter db = new DBAdapter(this); boolean filled = false; db.open(); for (int i = 1; i &lt;= 4; i++) { String change = db.getMajorTitle(value).getString(1); if (change == null) { filled = false; }else{ filled = true; } } db.close(); return filled; } </code></pre> <p>If someone copies this and it works can you please tell me what might be wrong with my emulator or eclipse or whatever. Thanks everyone for there input.</p> <p>FINISHED: I noticed that at another part in my program I changed null to "". I would like to thank everyone for being right and showing me different ways to code it.</p>
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    1. COWhat class is db? Are you showing us your own API? How would anyone know what happens inside it?
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      1. USAlex Gitelman
    2. COAre you getting an exception? `change.equals(null)` should throw an exception when change is null because you can't call members of null objects. Try `change == null` instead.
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