Add reply sorting by popularity and threaded reply support (楼中楼)

FEATURES.md

@@ -0,0 +1,76 @@
+# V2er 回复排序和楼中楼功能说明
+
+## 功能概述
+
+本次更新为 V2er 添加了两个重要功能：
+
+### 1. 回复按热门程度排序 (Reply Sorting by Popularity)
+
+用户现在可以在主题页面切换回复的排序方式：
+- **按时间排序** (默认) - 按回复时间顺序显示
+- **按热门排序** - 按感谢次数降序排列，感谢次数相同时按楼层排序
+
+#### 使用方法：
+1. 在主题页面点击右上角菜单
+2. 选择"按时间排序"或"按热门排序"来切换模式
+3. 设置会自动保存，下次打开时保持选择的排序方式
+
+### 2. 楼中楼功能 (Threaded Replies)
+
+系统会自动检测回复中的 @用户名 提及，并以可视化方式显示回复的层级关系：
+
+#### 特性：
+- 自动解析 `@username` 和 `@<a href="/member/username">username</a>` 格式
+- 根据提及关系计算缩进级别（最多3级）
+- 有回复关系的评论会有：
+  - 左侧缩进显示层级关系
+  - 楼层号后显示 💬 图标
+  - 浅色背景区分
+
+## 技术实现
+
+### 核心类修改：
+
+1. **TopicInfo.java**
+   - 添加 `processMentionsAndThreading()` 方法处理提及解析
+   - 添加 `extractMentions()` 方法使用正则表达式提取用户名
+   - 扩展 `getItems()` 方法支持排序模式参数
+
+2. **TopicActivity.java**
+   - 添加回复排序菜单项处理
+   - 实现 `refreshReplySorting()` 方法即时切换排序
+   - 集成排序模式状态管理
+
+3. **TopicReplyItemDelegate.java**
+   - 添加 `applyThreadIndentation()` 方法应用缩进样式
+   - 集成楼层显示和线程指示器
+
+4. **Reply 类增强**
+   - 添加 `mentionedUsers` 列表存储提及的用户
+   - 添加 `indentLevel` 字段控制缩进层级
+   - 提供相关的 getter/setter 方法
+
+### 新增组件：
+
+- **ReplySortMode.java** - 排序模式枚举类
+- **threaded_reply_background.xml** - 楼中楼回复背景样式
+- **ic_sort.xml** - 排序功能图标
+
+## 用户体验改进
+
+1. **直观的可视化** - 通过缩进和背景色清晰显示回复层级
+2. **状态持久化** - 排序偏好自动保存
+3. **性能优化** - 本地排序，无需重新加载网络数据
+4. **无侵入性** - 保持原有界面布局，仅添加新功能
+
+## 示例场景
+
+```
+1楼: 原始问题
+2楼: 直接回复问题
+3楼: @2楼用户 我也有同样问题 💬  [缩进显示]
+4楼: @3楼用户 试试这个方法 💬    [进一步缩进]
+5楼: 新的话题
+```
+
+通过这种方式，用户可以更容易地跟踪对话线程和找到最受欢迎的回复。

UI_MOCKUP.md

@@ -0,0 +1,77 @@
+# UI Changes Mockup
+
+## Before and After Comparison
+
+### 1. Menu Bar Changes
+```
+Before:
+[★] [分享] [逆序浏览] [⋮]
+
+After:  
+[★] [分享] [逆序浏览] [≡] [⋮]
+                       ↑
+                   New sort icon
+```
+
+### 2. Reply List - Time Sorting (Default)
+```
+1楼 ghui                    ♥ 5
+    This is the main question...
+
+2楼 user1                   ♥ 2  
+    Here's my answer...
+
+3楼 user2                   ♥ 8
+    @user1 I agree with your solution
+```
+
+### 3. Reply List - Popularity Sorting  
+```
+3楼 user2                   ♥ 8
+    @user1 I agree with your solution
+
+1楼 ghui                    ♥ 5
+    This is the main question...
+
+2楼 user1                   ♥ 2
+    Here's my answer...
+```
+
+### 4. Threaded Replies with Indentation
+```
+1楼 ghui                    ♥ 5
+    Original question here...
+
+2楼 alice                   ♥ 3
+    First response...
+
+    3楼 bob 💬               ♥ 1
+        @alice Good point!
+        [Subtle background, left margin]
+
+        4楼 charlie 💬       ♥ 0  
+            @bob Thanks for clarification
+            [More indented, different background]
+
+5楼 david                   ♥ 2
+    New topic discussion...
+```
+
+## Visual Indicators
+
+1. **Threading Indicator**: 💬 emoji after floor number
+2. **Indentation**: Progressive left margin for nested replies
+3. **Background**: Subtle gray background for threaded replies
+4. **Sorting**: Real-time toggle without page reload
+
+## User Flow
+
+1. User opens topic page → sees default time-based sorting
+2. User taps sort icon → switches to popularity sorting
+3. Replies reorder immediately showing most-thanked first
+4. Threading relationships shown with visual indentation
+5. User preference saved for future visits
+
+This provides both requested features:
+- **按热门程度显示** (Display by popularity) ✅
+- **楼中楼** (Threaded replies) ✅

app/src/main/java/me/ghui/v2er/general/Pref.java

@@ -30,6 +30,10 @@ public static int readInt(String key, int defaultValue) {
         return Prefs.with(app()).readInt(key, defaultValue);
     }
 
+    public static int readInt(@StringRes int key, int defaultValue) {
+        return readInt(app().getString(key), defaultValue);
+    }
+
     public static boolean readBool(@StringRes int key) {
         return readBool(app().getString(key));
     }
@@ -66,6 +70,10 @@ public static void save(String key, int value) {
         Prefs.with(app()).writeInt(key, value);
     }
 
+    public static void save(@StringRes int key, int value) {
+        Prefs.with(app()).writeInt(app().getString(key), value);
+    }
+
     public static void save(String key, boolean value) {
         Prefs.with(app()).writeBoolean(key, value);
     }

app/src/main/java/me/ghui/v2er/general/ReplySortMode.java

@@ -0,0 +1,35 @@
+package me.ghui.v2er.general;
+
+/**
+ * Reply sorting modes for topic replies
+ * Created for issue #41 - adding reply sorting by popularity
+ */
+public enum ReplySortMode {
+    BY_TIME(0, "按时间排序"),
+    BY_POPULARITY(1, "按热门排序");
+
+    private final int value;
+    private final String description;
+
+    ReplySortMode(int value, String description) {
+        this.value = value;
+        this.description = description;
+    }
+
+    public int getValue() {
+        return value;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public static ReplySortMode fromValue(int value) {
+        for (ReplySortMode mode : values()) {
+            if (mode.value == value) {
+                return mode;
+            }
+        }
+        return BY_TIME; // default
+    }
+}

app/src/main/java/me/ghui/v2er/module/topic/TopicActivity.java

@@ -130,6 +130,9 @@ public void onMapSharedElements(List<String> names, Map<String, View> sharedElem
     private boolean mIsHideReplyBtn;
     private boolean mIsLogin = UserUtils.isLogin();
     private boolean mIsScanInOrder = !Pref.readBool(R.string.pref_key_is_scan_in_reverse, false);
+    private me.ghui.v2er.general.ReplySortMode mReplySortMode = me.ghui.v2er.general.ReplySortMode.fromValue(
+            Pref.readInt(R.string.pref_key_reply_sort_mode, me.ghui.v2er.general.ReplySortMode.BY_TIME.getValue()));
+    private MenuItem mReplySortMenuItem;
 
     /**
      * @param topicId
@@ -222,6 +225,8 @@ protected void configToolBar(BaseToolBar toolBar) {
         replyMenuItem.setVisible(mIsHideReplyBtn);
         MenuItem scanOrderMenuItem = menu.findItem(R.id.action_scan_order);
         scanOrderMenuItem.setTitle(mIsScanInOrder ? "顺序浏览" : "逆序浏览");
+        mReplySortMenuItem = menu.findItem(R.id.action_reply_sort);
+        mReplySortMenuItem.setTitle(mReplySortMode.getDescription());
         mToolbar.setOnMenuItemClickListener(item -> {
             if (mTopicInfo == null) {
                 if (item.getItemId() == R.id.action_open_in_browser) {
@@ -321,6 +326,18 @@ protected void configToolBar(BaseToolBar toolBar) {
                     loadFromStart();
                     showLoading();
                     break;
+                case R.id.action_reply_sort:
+                    // Toggle reply sorting mode
+                    mReplySortMode = (mReplySortMode == me.ghui.v2er.general.ReplySortMode.BY_TIME) 
+                            ? me.ghui.v2er.general.ReplySortMode.BY_POPULARITY 
+                            : me.ghui.v2er.general.ReplySortMode.BY_TIME;
+                    mReplySortMenuItem.setTitle(mReplySortMode.getDescription());
+                    Pref.save(R.string.pref_key_reply_sort_mode, mReplySortMode.getValue());
+                    // Re-apply sorting to current data without reloading from network
+                    if (mTopicInfo != null) {
+                        refreshReplySorting();
+                    }
+                    break;
             }
             return true;
         });
@@ -598,7 +615,7 @@ public void fillView(TopicInfo topicInfo, int page) {
 
         }
         // TODO: 2019-06-23 save info from adapter
-        mAdapter.setData(topicInfo.getItems(isLoadMore, mIsScanInOrder), isLoadMore);
+        mAdapter.setData(topicInfo.getItems(isLoadMore, mIsScanInOrder, mReplySortMode), isLoadMore);
         if (!topicInfo.getContentInfo().isValid()) {
             onRenderCompleted();
         }
@@ -656,6 +673,20 @@ private void autoScroll() {
         }
     }
 
+    private void refreshReplySorting() {
+        if (mTopicInfo == null) return;
+
+        // Get current page info to maintain state
+        int currentPage = mPresenter.getPage();
+        boolean isLoadMore = mIsScanInOrder ? currentPage > 1 : currentPage != mTopicInfo.getTotalPage();
+
+        // Re-sort and update adapter with current sorting mode
+        mAdapter.setData(mTopicInfo.getItems(isLoadMore, mIsScanInOrder, mReplySortMode), isLoadMore);
+
+        // Update the @mention list as well
+        fillAtList();
+    }
+
     private void fillAtList() {
         List<TopicInfo.Item> datum = mAdapter.getDatas();
         if (repliersInfo == null) {

app/src/main/java/me/ghui/v2er/module/topic/TopicReplyItemDelegate.java

@@ -60,6 +60,9 @@ public void convert(ViewHolder holder, TopicInfo.Item item, int position) {
         } else {
             holder.getConvertView().setBackgroundColor(Color.TRANSPARENT);
         }
+
+        // Apply indentation for threaded replies
+        applyThreadIndentation(holder, replyInfo);
         holder.setText(R.id.reply_user_name_tv, replyInfo.getUserName());
         if (replyInfo.getLove() == 0) {
             holder.getView(R.id.reply_thx_tv).setVisibility(View.GONE);
@@ -88,7 +91,13 @@ public void convert(ViewHolder holder, TopicInfo.Item item, int position) {
         } else {
             contentView.setVisibility(View.GONE);
         }
-        holder.setText(R.id.floor_tv, replyInfo.getFloor());
+
+        // Update floor text with threading indicator
+        String floorText = replyInfo.getFloor();
+        if (replyInfo.hasMentions() && replyInfo.getIndentLevel() > 0) {
+            floorText += " 💬"; // Add emoji to indicate threaded reply
+        }
+        holder.setText(R.id.floor_tv, floorText);
     }
 
     public interface OnMemberClickListener {
@@ -117,4 +126,33 @@ public boolean onUrlClick(String url) {
         }
     }
 
+    /**
+     * Apply indentation for threaded replies based on mention depth
+     */
+    private void applyThreadIndentation(ViewHolder holder, TopicInfo.Reply replyInfo) {
+        View convertView = holder.getConvertView();
+
+        // Calculate indentation based on thread level
+        int indentLevel = replyInfo.getIndentLevel();
+        int baseIndent = (int) mContext.getResources().getDimension(R.dimen.common_padding_size);
+        int indentPixels = baseIndent + (indentLevel * baseIndent / 2); // 12dp base + 6dp per level
+
+        // Apply left margin to indicate thread level
+        if (convertView.getLayoutParams() instanceof android.view.ViewGroup.MarginLayoutParams) {
+            android.view.ViewGroup.MarginLayoutParams params = 
+                (android.view.ViewGroup.MarginLayoutParams) convertView.getLayoutParams();
+            params.leftMargin = indentPixels;
+            convertView.setLayoutParams(params);
+        }
+
+        // Visual indicator for threaded replies
+        if (indentLevel > 0 && replyInfo.hasMentions()) {
+            // Add a subtle visual indicator for threaded replies
+            convertView.setBackgroundResource(R.drawable.threaded_reply_background);
+        } else if (!replyInfo.isOwner() || !Pref.readBool(R.string.pref_key_highlight_topic_owner_reply_item)) {
+            // Reset background for non-threaded replies
+            convertView.setBackgroundColor(Color.TRANSPARENT);
+        }
+    }
+
 }