added hashtag example

2021-07-29 15:13:16 +05:30
parent 953d330bbe
commit 4985cb1904
2 changed files with 59 additions and 1 deletions
@@ -97,4 +97,62 @@ MessageListView(
        );
    },
 )
-```
+```
+
+### Adding Hashtags
+
+To add elements like hashtags, we can override the `textBuilder` in the MessageWidget:
+
+```
+MessageListView(
+    ...
+    messageBuilder: (context, messageDetails, messageList, defaultWidget) {
+        return defaultWidget.copyWith(
+            textBuilder: (context, message) {
+                final text = _replaceHashtags(message.text).replaceAll('\n', '\\\n');
+                final messageTheme = StreamChatTheme.of(context).ownMessageTheme;
+
+                return MarkdownBody(
+                    data: text,
+                    onTapLink: (
+                        String link,
+                        String href,
+                        String title,
+                        ) {
+                      // Do something with tapped hashtag
+                    },
+                    styleSheet: MarkdownStyleSheet.fromTheme(
+                      Theme.of(context).copyWith(
+                        textTheme: Theme.of(context).textTheme.apply(
+                          bodyColor: messageTheme.messageText.color,
+                          decoration: messageTheme.messageText.decoration,
+                          decorationColor: messageTheme.messageText.decorationColor,
+                          decorationStyle: messageTheme.messageText.decorationStyle,
+                          fontFamily: messageTheme.messageText.fontFamily,
+                        ),
+                      ),
+                    ).copyWith(
+                      a: messageTheme.messageLinks,
+                      p: messageTheme.messageText,
+                    ),
+                );
+            },
+        );
+    },
+)
+
+String _replaceHashtags(String text) {
+  RegExp exp = new RegExp(r"\B#\w\w+");
+  exp.allMatches(text).forEach((match){
+    text = text.replaceAll(
+        '${match.group(0)}', '[${match.group(0)}](${match.group(0).replaceAll(' ', '')})');
+  });
+  return text;
+}
+```
+
+We can replace the hashtags using RegEx and add links for the MarkdownBody which is done here in the
+`_replaceHashtags()` function.
+Inside the textBuilder, we use the `flutter_markdown` package to build our hashtags as links.
+
+![](../assets/hashtag_example.jpg)