Cordova file plugin - save file in device
<p>I'm having a lot of troubles saving files in Android.<br>
The project is a hybrid application developed with Ionic with these plugins:</p>

<pre><code>com.phonegap.plugins.fileopener 1.0.0 "File Opener"
com.telerik.plugins.nativepagetransitions 0.4.2 "Native Page Transitions"
cordova-plugin-compat 1.0.0 "Compat"
cordova-plugin-crosswalk-webview 2.0.0 "Crosswalk WebView Engine"
cordova-plugin-file 4.2.0 "File"
cordova-plugin-network-information 1.2.2-dev "Network Information"
cordova-plugin-whitelist 1.2.3-dev "Whitelist"
cordova-plugin-wkwebview-engine 1.0.4-dev "Cordova WKWebView Engine"
ionic-plugin-keyboard 2.2.1 "Keyboard"
</code></pre>

<p>Android platform version is <code>5.2.1</code><br>
The device I'm using is a <code>Samsung A7</code>  </p>

<p>This is an abstract from <code>AndroidManifest.xml</code></p>

<pre><code>&lt;uses-sdk android:minSdkVersion="16" android:targetSdkVersion="23" /&gt;
&lt;uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /&gt;
&lt;uses-permission android:name="android.permission.INTERNET" /&gt;
&lt;uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /&gt;
&lt;uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /&gt;
&lt;uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /&gt;
</code></pre>

<h1>Case1</h1>

<p>if I try with this snippet (actually working on another project) </p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var storagePath = "/storage/emulated/0";
var fileDir = cordova.file.externalDataDirectory.replace(cordova.file.externalRootDirectory, '');
var fileName = $scope.ngDocument.documentId + ".pdf"
var filePath = storagePath + "/" + fileDir + fileName;
$cordovaFile.writeFile(filePath, BINARY_ARR, {'append': false}).then(function(result) {}, function(err) {});</code></pre>
</div>
</div>
</p>

<p>I get <code>{"code":5,"message":"ENCODING_ERR"}</code> as Callback from the <code>$cordovaFile.writeFile</code>, no matter if I use absolute path, relative path, just the file name and no file is ever created.</p>

<h1>Case2</h1>

<p>With this snippet </p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function (fs) {
  console.log('file system open: ' + fs.name);
  fs.root.getFile(fileName, { create: true, exclusive: false }, function (fileEntry) {
    console.log("fileEntry:" + JSON.stringify(fileEntry));
    writeFile(fileEntry, BINARY_ARR);
  }, function(data){});
}, function(data){});</code></pre>
</div>
</div>
</p>

<p>happen two different things</p>

<h2>Case 2.1</h2>

<p>If no config options are specified in <code>config.xml</code> the app creates an empty folder into /storage/emulated/0/Android/media/{myAPP}</p>

<h2>Case 2.2</h2>

<p>with these two preferences</p>

<pre><code>&lt;preference name="AndroidPersistentFileLocation" value="Compatibility" /&gt;
&lt;preference name="AndroidExtraFilesystems" value="cache" /&gt;
</code></pre>

<p>a file in <code>/storage/emulated/0</code> (external SSD) is created and in <code>logcat</code>errors are:</p>

<pre><code>E/Vold    ( 2280): Failed to find mounted volume for /storage/extSdCard/Android/data/{myApp}/files/
W/Vold    ( 2280): Returning OperationFailed - no handler for errno 0
W/ContextImpl(13364): Failed to ensure directory: /storage/extSdCard/Android/data/{myApp}/files
E/Vold    ( 2280): Failed to find mounted volume for /storage/extSdCard/Android/data/{myApp}/files/
W/Vold    ( 2280): Returning OperationFailed - no handler for errno 0
W/ContextImpl(13364): Failed to ensure directory: /storage/extSdCard/Android/data/{myApp}/files
E/Vold    ( 2280): Failed to find mounted volume for /storage/extSdCard/Android/data/{myApp}/cache/
W/Vold    ( 2280): Returning OperationFailed - no handler for errno 0
W/ContextImpl(13364): Failed to ensure directory: /storage/extSdCard/Android/data/{myApp}/cache
</code></pre>

<p>The strange fact is that <code>/storage/extSdCard</code> (symbolic link for <code>/mnt/extSdCard</code>) is not mounted while the external SSD is mounted on <code>/mnt/sdcard</code> </p>

<p>Please help: I'm headbanging.<br>
The first snippet was working as a charm in another project. Could it be the version of ngCordova? </p>