更改：

1、只允许数字、英文字符和中文字符被转化为群友头像；
2、增加四个emoji。

Author: notxx

src/main/java/com/oasisfeng/nevo/decorators/wechat/ConversationManager.java

@@ -2,11 +2,13 @@
 
 import android.text.TextUtils;
 import android.util.ArrayMap;
+import android.util.Log;
 import android.util.SparseArray;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.Map;
+import java.util.regex.Pattern;
 
 import androidx.annotation.IntDef;
 import androidx.annotation.Nullable;
@@ -32,6 +34,7 @@ static class Conversation {
 		@IntDef({ TYPE_UNKNOWN, TYPE_DIRECT_MESSAGE, TYPE_GROUP_CHAT, TYPE_BOT_MESSAGE }) @Retention(RetentionPolicy.SOURCE) @interface ConversationType {}
 
 		private static final String SCHEME_ORIGINAL_NAME = "ON:";
+		private static final Pattern pattern = Pattern.compile("^[a-zA-Z0-9\\u4e00-\\u9fa5]");
 
 		final int id;
 		@Nullable String key;
@@ -71,7 +74,16 @@ Person getGroupParticipant(final String key, final String name) {
 			if (participant == null) builder = new Person.Builder().setKey(key);
 			else if (! TextUtils.equals(name, requireNonNull(participant.getUri()).substring(SCHEME_ORIGINAL_NAME.length())))	// Original name is changed
 				builder = participant.toBuilder();
-			if (builder != null) mParticipants.put(key, participant = builder.setUri(SCHEME_ORIGINAL_NAME + name).setName(EmojiTranslator.translate(name)).build());
+			if (builder != null) {
+				final CharSequence n = EmojiTranslator.translate(name);
+				builder.setUri(SCHEME_ORIGINAL_NAME + name);
+				if (pattern.matcher(n).find()) {
+					builder.setName(n);
+				} else {
+					builder.setName("\u200b" + n);
+				}
+				mParticipants.put(key, participant = builder.build());
+			}
 			return participant;
 		}
 
@@ -94,4 +106,5 @@ Conversation getConversation(final int id) {
 	}
 
 	private final SparseArray<Conversation> mConversations = new SparseArray<>();
+	private static final String TAG = WeChatDecorator.TAG;
 }

src/main/java/com/oasisfeng/nevo/decorators/wechat/EmojiMap.java

@@ -13,8 +13,12 @@ public class EmojiMap {
 	// Pull Request is welcome. (columns are split by "tab" for visual alignment)
 	// Proper emoji is needed for commented lines.
 	static final String[][] MAP = new String[][] {
-            { "表情",       null,           "㊙️" },
-            { "链接",       null,           "🔗" },
+			{ "表情",       null,           "㊙️" },
+			{ "链接",       null,           "🔗" },
+			{ "花",         null,           "🌺" },
+			{ "钱",         null,           "💰" },
+			{ "闪烁",       null,           "✨" },
+			{ "X",          "X",           "❌" },
 			{ "OK",			"OK",			"👌" },
 			{ "耶",			"Yeah!",		"✌" },
 			{ "嘘",			"Silent",		"🤫" },
@@ -114,7 +118,7 @@ public class EmojiMap {
 //			{ "机智",		"Smart",		"" },
 //			{ "抠鼻",		"DigNose",		"" },
 //			{ "可怜",		"Whimper",		"" },
-            { "皇冠",       null,           "👑" },
+			{ "皇冠",       null,           "👑" },
 			{ "快哭了",		"Puling",		"😔" },
 //			{ "左哼哼",		"Bah！L",		"" },
 //			{ "右哼哼",		"Bah！R",		"" },

src/main/java/com/oasisfeng/nevo/decorators/wechat/EmojiTranslator.java

@@ -17,10 +17,10 @@ public class EmojiTranslator {
 	private static final Map<String, String> ENGLISH_MAP = new HashMap<>(EmojiMap.MAP.length);
 	static {
 		for (final String[] entry : EmojiMap.MAP) {
-            if (entry[0] != null)
-    			CHINESE_MAP.put(entry[0], entry[2]);
-            if (entry[1] != null)
-	    		ENGLISH_MAP.put(entry[1], entry[2]);
+			if (entry[0] != null)
+				CHINESE_MAP.put(entry[0], entry[2]);
+			if (entry[1] != null)
+				ENGLISH_MAP.put(entry[1], entry[2]);
 		}
 	}
 

src/main/java/com/oasisfeng/nevo/decorators/wechat/MessagingBuilder.java

@@ -94,7 +94,7 @@ class MessagingBuilder {
 		final String redundant_prefix = title.toString() + SENDER_MESSAGE_SEPARATOR;
 		for (final StatusBarNotification each : archive) {
 			final Notification notification = each.getNotification();
-            tickerArray.put(notification.when, notification.tickerText);
+			tickerArray.put(notification.when, notification.tickerText);
 			final Bundle its_extras = notification.extras;
 			final CharSequence its_title = EmojiTranslator.translate(its_extras.getCharSequence(Notification.EXTRA_TITLE));
 			if (! title.equals(its_title)) {
@@ -130,7 +130,7 @@ class MessagingBuilder {
 		final boolean sender_inline = num_lines_with_colon == textArray.size();
 		for (int i = 0, size = textArray.size(); i < size; i++)	{		// All lines have colon in text
 			messaging.addMessage(buildMessage(conversation, textArray.keyAt(i), tickerArray.valueAt(i), textArray.valueAt(i), sender_inline ? null : title.toString()));
-        }
+		}
 		return messaging;
 	}
 
@@ -159,8 +159,8 @@ class MessagingBuilder {
 			Log.e(TAG, "Error parsing reply intent.", e);
 		}
 
-        final MessagingStyle messaging = buildFromArchive(conversation, n, title, archive);
-        final List<Message> messages = messaging.getMessages();
+		final MessagingStyle messaging = buildFromArchive(conversation, n, title, archive);
+		final List<Message> messages = messaging.getMessages();
 
 		final PendingIntent on_read = convs.getReadPendingIntent();
 		if (on_read != null) mMarkReadPendingIntents.put(sbn.getKey(), on_read);	// Mapped by evolved key,
@@ -358,8 +358,7 @@ interface Controller { void recastNotification(String key, Bundle addition); }
 	}
 
 	private static Person buildPersonFromProfile(final Context context) {
-		return new Person.Builder().setName(context.getString(R.string.self_display_name))
-				.setIcon(IconCompat.createWithContentUri(Uri.withAppendedPath(Profile.CONTENT_URI, Contacts.Photo.DISPLAY_PHOTO))).build();
+		return new Person.Builder().setName(context.getString(R.string.self_display_name)).build();
 	}
 
 	void close() {