refactor(ui): share single KeyboardWidget instance across screens

Moves KeyboardWidget from a per-screen value member to a single instance
owned by UITask, passed to SettingsScreen, QuickMsgScreen, and BotScreen
as a pointer. Only one screen is ever active at a time, so the shared
state is safe. Saves ~1.5 KB of always-resident heap.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

examples/companion_radio/ui-new/BotScreen.h

@@ -13,8 +13,8 @@ class BotScreen : public UIScreen {
   bool _dirty;
 
   // keyboard state (reused for trigger and reply fields)
-  int            _kb_field;   // -1=off, 2=trigger, 3=reply DM, 4=reply Ch
+  int             _kb_field;   // -1=off, 2=trigger, 3=reply DM, 4=reply Ch
-  KeyboardWidget _kb;
+  KeyboardWidget* _kb;
 
   // channel cache (refreshed on enter)
   int     _num_channels;
@@ -38,7 +38,7 @@ class BotScreen : public UIScreen {
   }
 
 public:
-  BotScreen(UITask* task, NodePrefs* prefs) : _task(task), _prefs(prefs) {}
+  BotScreen(UITask* task, NodePrefs* prefs, KeyboardWidget* kb) : _task(task), _prefs(prefs), _kb(kb) {}
 
   void enter() {
     _sel      = 0;
@@ -52,7 +52,7 @@ public:
     display.setColor(DisplayDriver::LIGHT);
 
     if (_kb_field >= 0) {
-      return _kb.render(display);
+      return _kb->render(display);
     }
 
     int avail_h = display.height() - display.listStart();
@@ -109,17 +109,17 @@ public:
     bool cancel = (c == KEY_CANCEL || c == KEY_CONTEXT_MENU);
 
     if (_kb_field >= 0) {
-      auto res = _kb.handleInput(c);
+      auto res = _kb->handleInput(c);
       if (res == KeyboardWidget::DONE) {
         if (_kb_field == 2) {
-          strncpy(_prefs->bot_trigger, _kb.buf, sizeof(_prefs->bot_trigger) - 1);
+          strncpy(_prefs->bot_trigger, _kb->buf, sizeof(_prefs->bot_trigger) - 1);
           _prefs->bot_trigger[sizeof(_prefs->bot_trigger) - 1] = '\0';
           for (char* p = _prefs->bot_trigger; *p; p++) *p = (char)tolower((uint8_t)*p);
         } else if (_kb_field == 3) {
-          strncpy(_prefs->bot_reply_dm, _kb.buf, sizeof(_prefs->bot_reply_dm) - 1);
+          strncpy(_prefs->bot_reply_dm, _kb->buf, sizeof(_prefs->bot_reply_dm) - 1);
           _prefs->bot_reply_dm[sizeof(_prefs->bot_reply_dm) - 1] = '\0';
         } else {
-          strncpy(_prefs->bot_reply_ch, _kb.buf, sizeof(_prefs->bot_reply_ch) - 1);
+          strncpy(_prefs->bot_reply_ch, _kb->buf, sizeof(_prefs->bot_reply_ch) - 1);
           _prefs->bot_reply_ch[sizeof(_prefs->bot_reply_ch) - 1] = '\0';
         }
         _dirty    = true;
@@ -180,9 +180,9 @@ public:
         initial = _prefs->bot_reply_ch;
         max     = sizeof(_prefs->bot_reply_ch) - 1;
       }
-      _kb.begin(initial, max);
+      _kb->begin(initial, max);
       if (_sel == 2) {
-        _kb.clearPlaceholders();  // trigger is literal text — placeholders never match incoming msgs
+        _kb->clearPlaceholders();  // trigger is literal text — placeholders never match incoming msgs
       } else {
         kbAddSensorPlaceholders(_kb, &sensors);
       }

examples/companion_radio/ui-new/QuickMsgScreen.h

@@ -45,7 +45,7 @@ class QuickMsgScreen : public UIScreen {
   static const int CH_HIST_MAX = 96;
 
   // KEYBOARD
-  KeyboardWidget _kb;
+  KeyboardWidget* _kb;
 
   // Context menu (opened by KEY_CONTEXT_MENU in CHANNEL_PICK / CONTACT_PICK / histories)
   PopupMenu _ctx_menu;
@@ -152,7 +152,7 @@ class QuickMsgScreen : public UIScreen {
   void beginShareCompose(bool channel) {
     _sending_to_channel = channel;
     _reply_mode = false;
-    _kb.begin(_share_text);
+    _kb->begin(_share_text);
     _phase = KEYBOARD;
   }
 
@@ -494,8 +494,8 @@ class QuickMsgScreen : public UIScreen {
   }
 
 public:
-  QuickMsgScreen(UITask* task)
+  QuickMsgScreen(UITask* task, KeyboardWidget* kb)
-    : _task(task), _phase(MODE_SELECT), _mode_sel(0),
+    : _task(task), _kb(kb), _phase(MODE_SELECT), _mode_sel(0),
       _contact_sel(0), _contact_scroll(0), _num_contacts(0), _room_mode(false),
       _channel_sel(0), _channel_scroll(0), _num_channels(0),
       _sel_channel_idx(0), _sending_to_channel(false),
@@ -1045,7 +1045,7 @@ public:
       if (_ctx_menu.active) _ctx_menu.render(display);
 
     } else if (_phase == KEYBOARD) {
-      return _kb.render(display);
+      return _kb->render(display);
 
     } else { // MSG_PICK
       char title[24];
@@ -1540,21 +1540,21 @@ public:
       }
 
     } else if (_phase == KEYBOARD) {
-      auto res = _kb.handleInput(c);
+      auto res = _kb->handleInput(c);
       if (res == KeyboardWidget::CANCELLED) {
         if (_share_mode) { _share_mode = false; _task->gotoHomeScreen(); }
         else             { _phase = MSG_PICK; }
       } else if (res == KeyboardWidget::DONE) {
         int prefix_len = _reply_mode ? (int)strlen(_reply_prefix) : 0;
-        if (_kb.len > prefix_len) {
+        if (_kb->len > prefix_len) {
           // Expand only the body — prefix "@[nick] " is preserved verbatim, so a nick
           // that happens to contain a placeholder token isn't substituted.
           char expanded[KB_MAX_LEN + 1];
           if (prefix_len > 0) {
-            memcpy(expanded, _kb.buf, prefix_len);
+            memcpy(expanded, _kb->buf, prefix_len);
-            expandMsg(_kb.buf + prefix_len, expanded + prefix_len, sizeof(expanded) - prefix_len);
+            expandMsg(_kb->buf + prefix_len, expanded + prefix_len, sizeof(expanded) - prefix_len);
           } else {
-            expandMsg(_kb.buf, expanded, sizeof(expanded));
+            expandMsg(_kb->buf, expanded, sizeof(expanded));
           }
           bool ok = sendText(expanded);
           afterSend(ok, expanded);
@@ -1581,7 +1581,7 @@ public:
       }
       if (c == KEY_ENTER) {
         if (_msg_sel == 0) {
-          _kb.begin(_reply_mode ? _reply_prefix : "");
+          _kb->begin(_reply_mode ? _reply_prefix : "");
           kbAddSensorPlaceholders(_kb, &sensors);
           _phase = KEYBOARD;
           return true;

examples/companion_radio/ui-new/SettingsScreen.h

@@ -572,12 +572,12 @@ class SettingsScreen : public UIScreen {
   }
 
   // Keyboard state for editing message slots
-  int           _edit_slot;  // -1 = not editing, 0..9 = slot being edited
+  int            _edit_slot;  // -1 = not editing, 0..9 = slot being edited
-  KeyboardWidget _kb;
+  KeyboardWidget* _kb;
 
 public:
-  SettingsScreen(UITask* task)
+  SettingsScreen(UITask* task, KeyboardWidget* kb)
-    : _task(task), _selected(SECTION_DISPLAY), _scroll(0), _visible(4), _dirty(false), _edit_slot(-1) {
+    : _task(task), _kb(kb), _selected(SECTION_DISPLAY), _scroll(0), _visible(4), _dirty(false), _edit_slot(-1) {
     buildVis();
   }
 
@@ -594,7 +594,7 @@ public:
     display.setTextSize(1);
 
     if (_edit_slot >= 0) {
-      return _kb.render(display);
+      return _kb->render(display);
     }
 
     int item_h  = display.lineStep();
@@ -629,10 +629,10 @@ public:
 
     // Keyboard editing mode for message slots
     if (_edit_slot >= 0) {
-      auto res = _kb.handleInput(c);
+      auto res = _kb->handleInput(c);
       if (res == KeyboardWidget::DONE) {
         if (p) {
-          strncpy(p->custom_msgs[_edit_slot], _kb.buf, sizeof(p->custom_msgs[0]) - 1);
+          strncpy(p->custom_msgs[_edit_slot], _kb->buf, sizeof(p->custom_msgs[0]) - 1);
           p->custom_msgs[_edit_slot][sizeof(p->custom_msgs[0]) - 1] = '\0';
           _dirty = true;
         }
@@ -834,7 +834,7 @@ public:
       _edit_slot = slot;
       // Bound to the custom_msgs store (140 B) so the wider keyboard buffer
       // can't overflow it on save.
-      _kb.begin(p ? p->custom_msgs[slot] : "",
+      _kb->begin(p ? p->custom_msgs[slot] : "",
                 p ? (int)sizeof(p->custom_msgs[slot]) - 1 : KB_MAX_LEN);
       kbAddSensorPlaceholders(_kb, &sensors);
       return true;

examples/companion_radio/ui-new/UITask.cpp

@@ -105,7 +105,6 @@ public:
 static const int QUICK_MSGS_MAX = 10;
 
 
-#include "KeyboardWidget.h"
 #include "FullscreenMsgView.h"
 #include "SensorPlaceholders.h"
 #include "SettingsScreen.h"
@@ -1198,11 +1197,11 @@ void UITask::begin(DisplayDriver* display, SensorManager* sensors, NodePrefs* no
 
   splash = new SplashScreen(this);
   home = new HomeScreen(this, &rtc_clock, sensors, node_prefs);
-  settings = new SettingsScreen(this);
+  settings = new SettingsScreen(this, &_kb);
-  quick_msg = new QuickMsgScreen(this);
+  quick_msg = new QuickMsgScreen(this, &_kb);
   tools_screen  = new ToolsScreen(this);
   ringtone_edit = new RingtoneEditorScreen(this, node_prefs);
-  bot_screen    = new BotScreen(this, node_prefs);
+  bot_screen    = new BotScreen(this, node_prefs, &_kb);
   nearby_screen = new NearbyScreen(this);
   dashboard_config = new DashboardConfigScreen(this, node_prefs);
   auto_advert_screen = new AutoAdvertScreen(this, node_prefs);

examples/companion_radio/ui-new/UITask.h

@@ -24,6 +24,7 @@
 #include "../NodePrefs.h"
 #include "../Trail.h"
 #include "../Waypoint.h"
+#include "KeyboardWidget.h"
 
 class UITask : public AbstractUITask {
   DisplayDriver* _display;
@@ -43,6 +44,7 @@ class UITask : public AbstractUITask {
   bool _lock_seq_used;             // true = suppress next back_btn CLICK (post-sequence release)
   char _alert[80];
   char _notif_mel_buf[220];  // persistent RTTTL buffer for custom notification melodies
+  KeyboardWidget _kb;        // shared across all screens — only one active at a time
   unsigned long _alert_expiry;
   int _msgcount;
   int _room_unread;