Complete secure log viewing and retention

app/src/main/java/se/ajpanton/notificationlog/SettingsFragment.kt

@@ -74,7 +74,7 @@ class SettingsFragment : Fragment(R.layout.fragment_settings) {
         }
         setupCopyControls()
         setupEventMasterToggles()
-        binding!!.exportLogs.setOnClickListener { chooseExportFormat() }
+        binding!!.exportLogs.setOnClickListener { confirmExport() }
         binding!!.clearLogs.setOnClickListener { confirmClearLogs() }
         val lockStore = AppLockStore(requireContext())
         binding!!.appLock.isChecked = lockStore.enabled
@@ -177,6 +177,15 @@ class SettingsFragment : Fragment(R.layout.fragment_settings) {
             .show()
     }
 
+    private fun confirmExport() {
+        MaterialAlertDialogBuilder(requireContext())
+            .setTitle("Export unencrypted logs?")
+            .setMessage("The exported file will not be encrypted. Anyone with access to its destination can read the selected log fields.")
+            .setNegativeButton("Cancel", null)
+            .setPositiveButton("Continue") { _, _ -> chooseExportFormat() }
+            .show()
+    }
+
     private fun writeExport(uri: Uri) {
         val format = pendingExport ?: return
         val context = requireContext().applicationContext