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lib/ui/tiles/conversation_message_tile.dart

@@ -60,7 +60,7 @@ class ConversationMessageTile extends StatelessWidget {
                       child: Icon(
                         Icons.more_vert,
                         color: Colors.white,
-                        size: 12,
+                        size: 14,
                       ),
                       onSelected: _menuOptionSelected,
                       itemBuilder: (c) => <PopupMenuItem<_MenuChoices>>[

lib/ui/widgets/conversation_file_tile.dart

@@ -1,3 +1,4 @@
+import 'package:cached_network_image/cached_network_image.dart';
 /// Chat file tile
 ///
 /// @author Pierre Hubert
@@ -10,6 +11,9 @@ import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:url_launcher/url_launcher.dart';
 
+const _AreaWidth = 150.0;
+const _AreaHeight = 100.0;
+
 class ConversationFileWidget extends StatefulWidget {
   final int messageID;
   final ConversationMessageFile file;
@@ -30,10 +34,25 @@ class _ConversationFileWidgetState extends State<ConversationFileWidget> {
   ConversationMessageFile get file => widget.file;
 
   @override
-  Widget build(BuildContext context) => Container(
-        width: 150,
-        height: 100,
-        child: _buildContent(),
+  Widget build(BuildContext context) => Stack(
+        children: [
+          !file.hasThumbnail
+              ? Container()
+              : Opacity(
+                  opacity: 0.8,
+                  child: CachedNetworkImage(
+                    imageUrl: file.thumbnail,
+                    width: _AreaWidth,
+                    height: _AreaHeight,
+                    fit: BoxFit.cover,
+                  ),
+                ),
+          Container(
+            width: _AreaWidth,
+            height: _AreaHeight,
+            child: _buildContent(),
+          )
+        ],
       );
 
   Widget _buildContent() {
@@ -60,7 +79,11 @@ class _ConversationFileWidgetState extends State<ConversationFileWidget> {
                   Spacer(flex: 2),
                   Icon(file.icon, color: Colors.white),
                   Spacer(),
-                  Text(file.name, textAlign: TextAlign.center),
+                  Text(
+                      file.name.length < 23
+                          ? file.name
+                          : file.name.substring(0, 20) + "...",
+                      textAlign: TextAlign.center),
                   Spacer(),
                   Text(
                     filesize(file.size),