DataStorage bug Fixed

.idea/misc.xml

@@ -37,7 +37,7 @@
     <ConfirmationsSetting value="0" id="Add" />
     <ConfirmationsSetting value="0" id="Remove" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" default="true" assert-keyword="true" jdk-15="true" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" default="true" assert-keyword="true" jdk-15="true" project-jdk-name="1.8" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">

app/src/main/java/com/example/brunoagrizzi/evologicabt/DataListener.java

@@ -210,7 +210,7 @@ public class DataListener extends AppCompatActivity {
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         int id = item.getItemId();
-
+        Boolean hasMsg = false;
         if (id == R.id.action_settings) {
             //Exporta dados
             DataStorage msgStore = new DataStorage();
@@ -219,15 +219,19 @@ public class DataListener extends AppCompatActivity {
                 String[] content = msg.get("content").toString().split(":");
                 responseData = responseData + msg.get("timestamp").toString() + "\t";
                 responseData = responseData + content[1] + "\n";
+                hasMsg = true;
             }
-            String[] initial = mMensagens.get(0).get("timestamp").toString().split(":");
-            String dataInitial = initial[0]+"_"+initial[1]+"_"+initial[2];
+            if (hasMsg) {
+                String[] initial = mMensagens.get(0).get("timestamp").toString().split(":");
+                String dataInitial = initial[0] + "_" + initial[1] + "_" + initial[2];
 
-            String[] finaly = mMensagens.get(mMensagens.size()-1).get("timestamp").toString().split(":");
-            String dataFinaly = finaly[0]+"_"+finaly[1]+"_"+finaly[2];
+                String[] finaly = mMensagens.get(mMensagens.size() - 1).get("timestamp").toString().split(":");
+                String dataFinaly = finaly[0] + "_" + finaly[1] + "_" + finaly[2];
 
-            msgStore.salvarExternalStorage(responseData,mConnectedDeviceName,dataInitial + "-" + dataFinaly);
-            Toast.makeText(DataListener.this, "Storage success" , Toast.LENGTH_SHORT).show();
+                msgStore.salvarExternalStorage(responseData, mConnectedDeviceName, dataInitial + "-" + dataFinaly);
+                Toast.makeText(DataListener.this, "Storage success", Toast.LENGTH_SHORT).show();
+            } else
+                Toast.makeText(DataListener.this, "No Message to save", Toast.LENGTH_SHORT).show();
             return true;
         }
         return super.onOptionsItemSelected(item);