criada as telas tela_avisos.dart, tela_detalhes_avisos.dart e tela_contatos.dart

lib/utils/dimensoes.dart

@@ -0,0 +1,13 @@
+import 'package:flutter/material.dart';
+
+class Dimensoes {
+  static MediaQueryData media = MediaQueryData();
+  static double width = 0.0;
+  static double height = 0.0;
+
+  void init(BuildContext context) {
+    media = MediaQuery.of(context);
+    width = media.size.width;
+    height = media.size.height;
+  }
+}