Display the name of the call

lib/helpers/conversations_helper.dart

@@ -143,6 +143,19 @@ class ConversationsHelper {
       return _conversationsDatabaseHelper.get(id);
   }
 
+  /// Get information about a conversation. The method throws an [Exception] in
+  /// case of failure
+  ///
+  /// Return value of this method is never null.
+  Future<Conversation> getSingleOrThrow(int id, {bool force = false}) async {
+    final conv = await this.getSingle(id, force: force);
+
+    if (conv == null)
+      throw Exception("Could not get information about the conversation!");
+
+    return conv;
+  }
+
   /// Get the name of a [conversation]. This requires information
   /// about the users of this conversation
   static String getConversationName(
@@ -187,7 +200,7 @@ class ConversationsHelper {
     }
   }
 
-  /// Asynchronously get the name fo the conversation
+  /// Asynchronously get the name of the conversation
   ///
   /// Unlike the synchronous method, this method does not need information
   /// about the members of the conversation

lib/ui/screens/call_screen.dart

@@ -1,3 +1,9 @@
+import 'package:comunic/helpers/conversations_helper.dart';
+import 'package:comunic/models/conversation.dart';
+import 'package:comunic/ui/widgets/comunic_back_button_widget.dart';
+import 'package:comunic/ui/widgets/safe_state.dart';
+import 'package:comunic/utils/intl_utils.dart';
+import 'package:comunic/utils/ui_utils.dart';
 import 'package:flutter/material.dart';
 
 /// Call screen
@@ -16,9 +22,67 @@ class CallScreen extends StatefulWidget {
   _CallScreenState createState() => _CallScreenState();
 }
 
-class _CallScreenState extends State<CallScreen> {
+class _CallScreenState extends SafeState<CallScreen> {
+  // Widget properties
+  int get convID => widget.convID;
+
+  // State properties
+  Conversation _conversation;
+  String _convName;
+  var _error = false;
+
+  @override
+  void initState() {
+    super.initState();
+    _initCall();
+  }
+
+  @override
+  void dispose() {
+    super.dispose();
+    _endCall();
+  }
+
+  void _initCall() async {
+    try {
+      setState(() => _error = false);
+
+      // First, load information about the conversation
+      _conversation = await ConversationsHelper().getSingleOrThrow(convID);
+      _convName =
+          await ConversationsHelper.getConversationNameAsync(_conversation);
+      assert(_convName != null);
+
+      setState(() {});
+    } catch (e, stack) {
+      print("Could not initialize call! $e\n$stack");
+      setState(() => _error = true);
+    }
+  }
+
+  void _endCall() async {}
+
   @override
   Widget build(BuildContext context) {
-    return Container();
+    return Scaffold(
+      appBar: AppBar(
+        leading: ComunicBackButton(),
+        title:
+            _convName == null ? CircularProgressIndicator() : Text(_convName),
+      ),
+      body: _buildBody(),
+    );
+  }
+
+  /// Build widget body
+  Widget _buildBody() {
+    if (_error)
+      // Handle errors
+      return buildErrorCard(tr("Could not initialize call!"), actions: [
+        MaterialButton(
+          onPressed: () => _initCall(),
+          child: Text(tr("Try again").toUpperCase()),
+        )
+      ]);
   }
 }