Let the app handle the back key event first (#126)

* Let the app handle the back key event first

* Tidy up

Author: swift-kim

shell/platform/tizen/channels/key_event_channel.cc

@@ -21,6 +21,7 @@ constexpr char kTypeKey[] = "type";
 constexpr char kModifiersKey[] = "modifiers";
 constexpr char kToolkitKey[] = "toolkit";
 constexpr char kUnicodeScalarValuesKey[] = "unicodeScalarValues";
+constexpr char kHandledKey[] = "handled";
 
 constexpr char kKeyUp[] = "keyup";
 constexpr char kKeyDown[] = "keydown";
@@ -226,10 +227,9 @@ KeyEventChannel::KeyEventChannel(BinaryMessenger* messenger)
 
 KeyEventChannel::~KeyEventChannel() {}
 
-void KeyEventChannel::SendKeyEvent(Ecore_Event_Key* key, bool is_down) {
-  FT_LOGI("code: %d, name: %s, mods: %d, type: %s", key->keycode, key->keyname,
-          key->modifiers, is_down ? kKeyDown : kKeyUp);
-
+void KeyEventChannel::SendKeyEvent(Ecore_Event_Key* key,
+                                   bool is_down,
+                                   std::function<void(bool)> callback) {
   int gtk_keycode = 0;
   if (kKeyCodeMap.count(key->keycode) > 0) {
     gtk_keycode = kKeyCodeMap.at(key->keycode);
@@ -254,7 +254,15 @@ void KeyEventChannel::SendKeyEvent(Ecore_Event_Key* key, bool is_down) {
   } else {
     event.AddMember(kTypeKey, kKeyUp, allocator);
   }
-  channel_->Send(event);
+  channel_->Send(event, [callback = std::move(callback)](const uint8_t* reply,
+                                                         size_t reply_size) {
+    if (reply != nullptr) {
+      auto decoded = flutter::JsonMessageCodec::GetInstance().DecodeMessage(
+          reply, reply_size);
+      bool handled = (*decoded)[kHandledKey].GetBool();
+      callback(handled);
+    }
+  });
 }
 
 }  // namespace flutter

shell/platform/tizen/channels/key_event_channel.h

@@ -21,7 +21,9 @@ class KeyEventChannel {
   explicit KeyEventChannel(BinaryMessenger* messenger);
   virtual ~KeyEventChannel();
 
-  void SendKeyEvent(Ecore_Event_Key* key, bool is_down);
+  void SendKeyEvent(Ecore_Event_Key* key,
+                    bool is_down,
+                    std::function<void(bool)> callback);
 
  private:
   std::unique_ptr<BasicMessageChannel<rapidjson::Document>> channel_;

shell/platform/tizen/key_event_handler.cc

@@ -4,12 +4,20 @@
 
 #include "key_event_handler.h"
 
-#include "flutter/shell/platform/tizen/flutter_tizen_engine.h"
+#include <app.h>
 
-static constexpr char kPlatformBackButtonName[] = "XF86Back";
+#include "flutter/shell/platform/tizen/flutter_tizen_engine.h"
+#include "flutter/shell/platform/tizen/tizen_log.h"
 
 namespace flutter {
 
+namespace {
+
+constexpr char kBackKey[] = "XF86Back";
+constexpr char kExitKey[] = "XF86Exit";
+
+}  // namespace
+
 KeyEventHandler::KeyEventHandler(FlutterTizenEngine* engine) : engine_(engine) {
   key_event_handlers_.push_back(
       ecore_event_handler_add(ECORE_EVENT_KEY_DOWN, OnKey, this));
@@ -30,24 +38,34 @@ Eina_Bool KeyEventHandler::OnKey(void* data, int type, void* event) {
   auto* engine = self->engine_;
   auto is_down = type == ECORE_EVENT_KEY_DOWN;
 
-  if (strcmp(key->keyname, kPlatformBackButtonName) == 0) {
-    // The device back button was pressed.
-    if (engine->navigation_channel && !is_down) {
-      engine->navigation_channel->PopRoute();
-    }
-  } else {
-    if (engine->text_input_channel) {
-      if (is_down) {
-        engine->text_input_channel->OnKeyDown(key);
-      }
-      if (engine->text_input_channel->IsSoftwareKeyboardShowing()) {
-        return ECORE_CALLBACK_PASS_ON;
-      }
+  FT_LOGI("Keycode: %d, name: %s, mods: %d, is_down: %d", key->keycode,
+          key->keyname, key->modifiers, is_down);
+
+  if (engine->text_input_channel) {
+    if (is_down) {
+      engine->text_input_channel->OnKeyDown(key);
     }
-    if (engine->key_event_channel) {
-      engine->key_event_channel->SendKeyEvent(key, is_down);
+    if (engine->text_input_channel->IsSoftwareKeyboardShowing()) {
+      return ECORE_CALLBACK_PASS_ON;
     }
   }
+
+  if (engine->key_event_channel) {
+    engine->key_event_channel->SendKeyEvent(
+        key, is_down,
+        [engine, keyname = std::string(key->keyname), is_down](bool handled) {
+          if (handled) {
+            return;
+          }
+          if (keyname == kBackKey && !is_down) {
+            if (engine->navigation_channel) {
+              engine->navigation_channel->PopRoute();
+            }
+          } else if (keyname == kExitKey && !is_down) {
+            ui_app_exit();
+          }
+        });
+  }
   return ECORE_CALLBACK_PASS_ON;
 }