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copied!<h2>Background information</h2> <p>The message means that Android has setup a dummy <code>ClassLoader</code> with <code>Thread.currentThread().setContextClassLoader()</code>, and something tries to use that dummy class loader. The <em>something</em> can be a lot of things, it's hard to tell exactly what from the information given. There is a trick you can try though, see below. Anyway, Android sets up the dummy class loader when there is a risk that the process might contain code from more than one APK. More specifically, Android looks in your manifest if you have used <code>android:sharedUserId</code>:</p> <pre><code><manifest xmlns:android="http://schemas.android.com/apk/res/android" ... android:sharedUserId="triggers.dummy.loader" > </code></pre> <p>or if you run in a non-standard <code>android:process</code></p> <pre><code> <application android:process="triggers.dummy.loader"> </code></pre> <h2>How to get rid of the warning</h2> <p>There are two things you can do to get rid of the warning:</p> <ol> <li>Don't use <code>android:sharedUserId</code> or <code>android:process</code></li> <li>Explicitly set what APK <code>ClassLoader</code> to use before running any other code</li> </ol> <p>To go with solution 2, there are some key insights you need. First, for any class <code>AnyClass</code> in an APK, <code>AnyClass.class.getClassLoader()</code> will return the same <code>ClassLoader</code>. Second,</p> <pre><code>AnyClass obj = new AnyClass(); Thread.currentThread().setContextClassLoader(obj.getClass().getClassLoader()) </code></pre> <p>is the same as</p> <pre><code>Thread.currentThread().setContextClassLoader(AnyClass.class.getClassLoader()) </code></pre> <p>Third, you need to call <code>Thread.currentThread().setContextClassLoader(getClass().getClassLoader())</code> before the code that calls <code>Thread.currentThread().getContextClassLoader()</code>. Fourth, When many APKs are involved, you need to call <code>Thread.setContextClassLoader(getClass().getClassLoader())</code> <em>after</em> the last APK has been loaded (otherwise loading the last APK will overwrite what you have set manually). Because of that, it would be a good idea to find out who is using the context class loader in you case by using the below debug trick. Then, right before that, you call <code>Thread.setContextClassLoader(getClass().getClassLoader())</code> for a class from the desired APK, typically the APK that is loaded first (or, in the case when only one APK is involved, that APK ;). Fifth, the context class loader is <em>per thread</em>, which you need to keep in mind if your application is multi-threaded.</p> <h2>Debug trick</h2> <p>If you want to find out what code that calls ClassLoader.getResources(), this should work:</p> <pre><code>Thread.currentThread().setContextClassLoader(new ClassLoader() { @Override public Enumeration<URL> getResources(String resName) throws IOException { Log.i("Debug", "Stack trace of who uses " + "Thread.currentThread().getContextClassLoader()." + "getResources(String resName):", new Exception()); return super.getResources(resName); } }); </code></pre> <p>if you do this early enough, you should see in the logcat a stack trace that goes back to whoever calls <code>getResources()</code> on the dummy class loader.</p>

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