How am i supposed to share images from my app exactly?

Issue

I'm completely new to sharing content between apps, in my app i have images that the user would be able to share, they are stored in drawable for a start but when sharing i write a separate file for the desired image and share it and use fileprovider in the process (i don't even understand what that is). i keep getting all kinds of permession erros like:

java.io.FileNotFoundException: /storage/emulated/0/Documents/image.png: open failed: EACCES (Permission denied)

or

java.io.FileNotFoundException: /storage/emulated/0/image.png: open failed: EPERM (Operation not permitted)

for android 13+ requesting read/write external storage permissions is useless and requesting manage external storage might keep your app off google play store.

so how am i supposed to do this exactly? what's the way?

my current code

val varName = "p_$muhImage"
val resourceId: Int =context.getResources().getIdentifier(varName, "drawable", context.packageName)

val bitmap =BitmapFactory.decodeResource(context.resources, resourceId)
val path= Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS).toString() + "/image.png"
                            try {
                                FileOutputStream(path).use { out ->
                                    bitmap.compress(
                                        Bitmap.CompressFormat.PNG,
                                        100,
                                        out
                                    )
                                }
                            } catch (e: IOException) {
                                e.printStackTrace()
                            }
                            val shareIntent = Intent(Intent.ACTION_SEND)
                            shareIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK)
                            shareIntent.type = "image/*"
                            val imageUri = FileProvider.getUriForFile(
                                context,
                                context.getPackageName() + ".fileprovider",
                                File(path)
                            )
                            shareIntent.putExtra(Intent.EXTRA_STREAM, imageUri)

                            shareIntent.putExtra(Intent.EXTRA_TITLE, "share")
                            shareIntent.putExtra(Intent.EXTRA_TEXT, "share")

                            val chooserIntent = Intent.createChooser(shareIntent, "share")
                            chooserIntent.putExtra(Intent.EXTRA_TITLE, "share")
                            chooserIntent.putExtra(Intent.EXTRA_TEXT, "share")
                            chooserIntent.putExtra(Intent.EXTRA_CONTENT_QUERY, "image/*")

                            context.startActivity(
                                Intent.createChooser(
                                    shareIntent,
                                    "share too"
                                )
                            );

                            File(path).deleteOnExit();

manifest permissions

    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

manifest provider

        <provider
            android:name="androidx.core.content.FileProvider"
            android:authorities="${applicationId}.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider"/>
        </provider>

provider xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="."/>
</paths>

Solution

Generally speaking, if you want to share content, you do not need to put it on external storage. Internal storage, especially a cache directory like getCacheDir() on Context, will suffice, when paired with FileProvider.

So, I recommend that you:

• Switch to getCacheDir() on Context for where to put your file
• Update the FileProvider XML metadata to match that
• Use image/png for the MIME type (the actual MIME type of the content), instead of image/*

Answered By - CommonsWare