退出前先保存数据，避免时序问题导致主界面没有获取到最新数据

app/src/main/java/com/xypower/mpremote/SettingsActivity.java

@@ -54,20 +54,14 @@ public class SettingsActivity extends AppCompatActivity {
     @Override
     protected void onDestroy() {
         super.onDestroy();
-
-        SharedPreferences preferences = getSharedPreferences("mpremote", MODE_PRIVATE);
-
-        SharedPreferences.Editor editor = preferences.edit();
-        editor.putString("password", binding.editViewPassword.getText().toString());
-        editor.putBoolean("usingGateway", binding.gatewayIp.isChecked());
-        editor.putString("assignedIp", binding.ip.getText().toString());
-        editor.commit();
+        saveSettings();
     }
 
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
             case android.R.id.home:
+                saveSettings();
                 setResult(0);
                 finish();
                 return false;
@@ -75,4 +69,14 @@ public class SettingsActivity extends AppCompatActivity {
                 return super.onOptionsItemSelected(item);
         }
     }
+
+    protected void saveSettings() {
+        SharedPreferences preferences = getSharedPreferences("mpremote", MODE_PRIVATE);
+
+        SharedPreferences.Editor editor = preferences.edit();
+        editor.putString("password", binding.editViewPassword.getText().toString());
+        editor.putBoolean("usingGateway", binding.gatewayIp.isChecked());
+        editor.putString("assignedIp", binding.ip.getText().toString());
+        editor.commit();
+    }
 }