Works

app/src/main/java/de/server47/smsexport/MainActivity.java

@@ -10,7 +10,10 @@ import android.widget.Button;
 
 import androidx.annotation.Nullable;
 
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 
 public class MainActivity extends Activity
@@ -34,12 +37,51 @@ public class MainActivity extends Activity
             @Override
             public void onClick(View v)
             {
-                readMessages(typeICS);
+                List<Map<String,String>> response = readMessages(typeICS);
+                if(response.size() > 0)
+                {
+                    StringBuilder export = new StringBuilder();
+
+                    export.append("<?xml-stylesheet type=\"text/xsl\" href=\"sms.xsl\"?>");
+                    export.append("<smses count=\"" + String.valueOf(response.size()) + "\"");
+                    export.append("backup_set=\"c6e0fda0-9bc0-48e2-893f-10ec95966e70\"");
+                    export.append("backup_date=\"1631273111057\"");
+                    export.append("type=\"full\">");
+//                    05.05.2001 19:15:00
+                    String pattern = "dd-MM-yyyy H:m:s";
+                    SimpleDateFormat simpleDateFormat = new SimpleDateFormat(pattern);
+
+                    for(int i = 0; i < response.size(); i++)
+                    {
+                        export.append(
+                "<sms protocol=\"0\"" +
+                        "address=\"" + response.get(i).get("remote_uri").replace("tel:", "") + "\"" +
+                        "date=\"" + response.get(i).get("date") + "\"" +
+                        "type=\"1\"" +
+                        "subject=\"null\"" +
+                        "body=\"" + response.get(i).get("body") + "\"" +
+                        "toa=\"null\"" +
+                        "sc_toa=\"null\"" +
+                        "service_center=\"null\"" +
+                        "read=\"1\"" +
+                        "status=\"-1\"" +
+                        "locked=\"0\"" +
+                        "date_sent=\"0\"" +
+                        "sub_id=\"-1\"" +
+                        "readable_date=\"" + 05.05.2001 19:15:00 + "\"" +
+                        "contact_name=\"(Unknown)\"/>";
+                        response.get(i).get()
+                        );
+                    }
+
+                    export.append("</smses>");
+
+                }
             }
         });
     }
 
-    void readMessages(int messageType)
+    List<Map<String,String>> readMessages(int messageType)
     {
         // public static final String INBOX = "content://sms/inbox";
         // public static final String SENT = "content://sms/sent";
@@ -63,6 +105,8 @@ public class MainActivity extends Activity
                 break;
         }
 
+        List<Map<String,String>> returnList = new ArrayList<>();
+
         Cursor cursor = getContentResolver().query(path, null, null, null, null);
 
         if (cursor.moveToFirst())
@@ -82,7 +126,7 @@ public class MainActivity extends Activity
                 }
                 Log.i("Message",  "Message nr. " + messageCounter  + " " + message);
 
-                // use msgData
+                returnList.add(messageMap);
             }
             while (cursor.moveToNext());
         }
@@ -91,5 +135,7 @@ public class MainActivity extends Activity
             // empty box, no SMS
             Log.i("message", "no messages");
         }
+
+        return returnList;
     }
-}
+}