Fixed crash and added more options to backup

app/src/main/java/code/name/monkey/retromusic/util/BackupUtil.kt

@@ -0,0 +1,30 @@
+package code.name.monkey.retromusic.util
+
+import android.content.Context
+import android.content.Intent
+import android.widget.Toast
+import androidx.core.content.FileProvider
+import java.io.File
+
+object BackupUtil {
+    fun createShareFileIntent(file: File, context: Context): Intent? {
+        return try {
+            Intent().setAction(Intent.ACTION_SEND).putExtra(
+                Intent.EXTRA_STREAM,
+                FileProvider.getUriForFile(
+                    context,
+                    context.applicationContext.packageName,
+                    file
+                )
+            ).addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION).setType("*/*")
+        } catch (e: IllegalArgumentException) {
+            e.printStackTrace()
+            Toast.makeText(
+                context,
+                "Could not share this file.",
+                Toast.LENGTH_SHORT
+            ).show()
+            Intent()
+        }
+    }
+}