title: java.lang.ClassNotFoundException: Didn't find class "android.support.v4.content.FileProvider" error in Adone AIR native extension
body: <p>maybe my question sounds like asked 100 times before, but believe me I have read every answer for those 100 similar questions and non of them solved my problem. So purpose of my native extension is to share documents in my app cache folder (doc, pdf, etc.) with third party apps (Quick Office, Adobe Reader etc). I found that FileProvider and Intents should solve my problem.</p>
  
  <p>My app description file contains:</p>
  
  <pre><code>&lt;application android:enabled="true"
                  android:launchMode="singleInstance"&gt;
                  &lt;provider
                      android:name="android.support.v4.content.FileProvider"
                      android:authorities="com.test.fileprovider"
                      android:exported="false"
                      android:grantUriPermissions="true"&gt;
                      &lt;meta-data
                          android:name="android.support.FILE_PROVIDER_PATHS"
                          android:resource="@xml/file_paths" /&gt;
                  &lt;/provider&gt;
              &lt;/application&gt;
  </code></pre>
  
  <p>In Eclipse in Project properties -> Java Build Path -> Order and Export selected: Android Private libraries and Android Dependencies.  android-support-v4.jar is inside project's libs folder. </p>
  
  <p>FREFunction code excerpt:</p>
  
  <pre><code>package com.test.OpenWithDefaultApp.functions;
  
  .....
  
  import android.content.Intent;
  import android.net.Uri;
  import android.support.v4.content.FileProvider;
  
  .....
  
  Uri contentUri = FileProvider.getUriForFile(context.getActivity(), "com.test.OpemWithDefaultApp.fileprovider", file);
              Intent intent = new Intent(Intent.ACTION_VIEW);
              intent.setDataAndType(contentUri, fileType);
  
  .....
  
  context.getActivity().startActivity(intent);
  
  .....
  </code></pre>
  
  <p>I'm using </p>
  
  <pre><code>Eclipse Luna 4.4.0
  Eclipse Android Plugin 23.0.3
  Android SDK Tools 23.0.2
  Android SDK Platform-tools 20
  Android SDK Build-tools 20
  Android SDK from 14 upto 20
  Android Support Library 20
  Google Play services 19
  </code></pre>
  
  <p>Native extension structure:</p>
  
  <pre><code>+android
        -libs/android-support-v4.jar
        -res/xml/file_paths
        -library.swf
        -openwithdefaultapp.jar
  +default
        -library.swf
  -extension.xml
  </code></pre>
  
  <p>But I'm stuck with error:</p>
  
  <pre><code>java.lang.RuntimeException: Unable to get provider android.support.v4.content.FileProvider: java.lang.ClassNotFoundException: Didn't find class "android.support.v4.content.FileProvider" on path: DexPathList[[zip file "/data/app/air.testFileProvider-2.apk"],nativeLibraryDirectories=[/data/app-lib/air.testFileProvider-2, /vendor/lib, /system/lib]]
  </code></pre>
  
  <p>Any help would be appreciated. 
  Thanks</p>