Sharing Files in Android with other Apps in the Device

Generally, in Android, file sharing from one app with another app happens in the form of content URI. So, you need to make your app generate content URIs of files that you want to share with other apps.

To share a file from your app with other apps

  1. Specify the sharable directories in the XML file
  2. Specify the FileProvider in the Manifest Properties
  3. Create or copy the sharable files to the shared directory

Specifying the Sharable Directories in the XML file

Kony platform does not share any directory of an app by default due to security concerns. To share directories or files with other apps is under your control. So, to share files with other apps, you must explicitly specify sharable directories in your app. You can specify the shared directories using an XML file.

To specify the shared directories

  1. Create an XML file. For example, filepaths.xml.
  2. Place the XML file at the workspace/resources/mobile/native/android/xml subdirectory in your mobile app project directory.

    3. NOTE: If your Android app is for tablet, place the file at the workspace/resources/tablet/native/android/xml subdirectory.

  3. In the XML file, add the <paths></paths>tag as parent element, and then add the directories of the files you want to share as child elements inside the parent element. You can specify multiple directories in the parent element. Below is a sample path defined in the XML file (filepaths.xml).

    4. <paths>

       <files-path path="images/" name="myimages"/>

    </paths>

    If you want to share multiple directories, below is a sample:

    <paths>

       <files-path path="images/" name="myimages"/>

       <files-path path="videos/" name="myvideos"/>

        <external-path path="Documents/" name="mypublicdocs"/>

    </paths>

  4. Use any of the following child elements inside the <paths></paths> parent element to specify the directories that contain sharable files.
    • <file-path>: to specify the subdirectories within the files/ directory in your app’s internal storage. The directory is the same as the value returned by kony.io.FileSystem.getDataDirectoryPath().

      • <files-path path="images/" name="myimages"/>

  5. Within the child element tags, you must specify the attribute, path to define the directory path where the sharable files are located. If you want to share files and directories in the root directory, specify the value of the pathattribute as "/". Otherwise, specify the subdirectory path. For example, "images/".

    6. NOTE: Make sure that the subdirectories that you defined in the path attribute are already created at the root directory using the kony.io.File API.

  6. The name attribute indicates the path segment in the generated content URI for the files located in the shared directory. When multiple directories are shared, define the name attribute separately for each directory shared by the path element.

The name of the XML file (filepaths.xml) that you have created with the shared directories should be specified as the value to the attribute, android:resource in the FileProvider Manifest Properties.

android:resource="@xml/<filename>".

In the example, replace the <filename> with the name of the XML file. For example, filepaths. Make sure that the extension, .xml is not specified along with the file name.

Specifying the FileProvider in the Manifest Properties

FileProvider is a mechanism provided by Android to generate content URIs of the files to be shared with other apps. The XML file with sharable directories is passed to the FileProvider for generating the content URI. Based on the specifications defined in the XML file, the FileProvider generates content URIs of file objects.

To specify the FileProvider in the Manifest

  1. Open the app, and click Project Settings. The Project Settings dialog opens.
  2. Click the Native tab, and then click Android sub-tab.
  3. Under the ManifestProperties, click the Tags tab.
  4. In the Application Tag Attributes box, copy and paste the following code snippet.

    5. <provider
      android:name="androidx.core.content.FileProvider"
      android:authorities="com.orgname.Sample"
      android:exported="false"
      android:grantUriPermissions="true">
      <meta-data
         android:name="android.support.FILE_PROVIDER_PATHS"
         android:resource="@xml/filepaths" />
    </provider>

    In the code snippet, the values specified for the android:authorities and android:resource attributes are just examples. For the android:authorities attribute, you must replace the value with the package name of your Android app. For the android:resource attribute, you must replace only the filepaths string with the file name of the XML file.

    NOTE: Ensure that you add the {implementation 'androidx.core:core:+'} in the build.gradle entries to Suffix field of the Project Settings > Native > Android Mobile/Tablet section.

    NOTE: Make sure that the extension, .xml is not specified along with the file name of the XML file.

Creating Files in the Shared Directories

Create or copy files that you want to share in the shared directories.

To share the raw bytes returned from the Image Widget, kony.image.createImage, and kony.image.createImageFromSnapshot functions, save the raw bytes as files using the kony.io.File API in the shared directories. The file raw bytes returned by the kony.io.File API can be used for sharing with other apps.

Use Case: Attaching a File to an Email

When an end-user wants to attach a file from your app to an Email, you must invoke the kony.phone.openEmail function. When invoking the kony.phone.openEmail function from an Android app, the attachment parameter must be raw bytes. You can directly pass the raw bytes received from the kony.camera (only public access mode) and kony.phone.openMediaGallery APIs as the attachment parameter. Because, the raw bytes received from these sources already contain content URI.

To support raw bytes obtained from the following sources as an attachment in the kony.phone.openEmail API, you must follow the Sharing a File in Android with other Apps procedure.

Here is a sample code of passing an image file, which is converted into content URI, in the attachment parameter of the kony.phone.openEmail function.

var testImg = kony.image.createImageFromSnapShot(frmHome.Flxgrp);
frmHome.Img2.image = testImg;
var testRaw = testImg.getImageAsRawBytes();
var path =kony.io.FileSystem.getDataDirectoryPath();
var sharedDir = path+constants.FILE_PATH_SEPARATOR+"images";
var sharefolder = new kony.io.File(sharedDir).createDirectory();
var fileLoc = sharedDir+constants.FILE_PATH_SEPARATOR+"myimage.jpg";
var myfile=new kony.io.File(fileLoc).createFile();
var write=new kony.io.File(fileLoc).write(testRaw);
var fileRawBytes=new kony.io.File(fileLoc).read();
var to = ["Abcd@kony.com"];
var cc = ["Abcd@gmail.com"];
var bcc = ["Abcd@kony.com"];
var sub = "Testing Screenshot attachment";
var msgbody = "Testing openEmail with attachment";
var attachment = {mimetype: "image/*",attachment: fileRawBytes };
kony.phone.openEmail(to, cc, bcc, sub, msgbody, false, [attachment]);