Improve DFU procedure :

- correctly write all bytes to flash
 - check CRC
 - Fix bug in notification : they cannot be sent from the control point handler (because it seems you cannot send a notification and a write acknowledge at the same time) using a timer (quick'n'dirty implementation to be improved)
 - Improve dfu screen
 - Reset if dfu image is correctly copied into flash and crc is ok.

src/DisplayApp/Screens/FirmwareUpdate.cpp

@@ -26,6 +26,15 @@ FirmwareUpdate::FirmwareUpdate(Pinetime::Applications::DisplayApp *app, Pinetime
   lv_label_set_text(percentLabel, "");
   lv_obj_set_auto_realign(percentLabel, true);
   lv_obj_align(percentLabel, bar1, LV_ALIGN_OUT_TOP_MID, 0, 60);
+
+  button = lv_btn_create(lv_scr_act(), NULL);
+  //lv_obj_set_event_cb(button, event_handler);
+  lv_obj_align(button, NULL, LV_ALIGN_IN_BOTTOM_MID, 0, 0);
+  lv_obj_set_hidden(button, true);
+
+  labelBtn = lv_label_create(button, NULL);
+  lv_label_set_text(labelBtn, "Back");
+  lv_obj_set_hidden(labelBtn, true);
 }
 
 FirmwareUpdate::~FirmwareUpdate() {
@@ -33,6 +42,29 @@ FirmwareUpdate::~FirmwareUpdate() {
 }
 
 bool FirmwareUpdate::Refresh() {
+  switch(bleController.State()) {
+    default:
+    case Pinetime::Controllers::Ble::FirmwareUpdateStates::Idle:
+    case Pinetime::Controllers::Ble::FirmwareUpdateStates::Running:
+      if(state != States::Running)
+        state = States::Running;
+      return DisplayProgression();
+    case Pinetime::Controllers::Ble::FirmwareUpdateStates::Validated:
+      if(state != States::Validated) {
+        UpdateValidated();
+        state = States::Validated;
+      }
+      return running;
+    case Pinetime::Controllers::Ble::FirmwareUpdateStates::Error:
+      if(state != States::Error) {
+        UpdateError();
+        state = States::Error;
+      }
+      return running;
+  }
+}
+
+bool FirmwareUpdate::DisplayProgression() const {
   float current = bleController.FirmwareUpdateCurrentBytes() / 1024.0f;
   float total = bleController.FirmwareUpdateTotalBytes() / 1024.0f;
   int16_t pc = (current / total) * 100.0f;
@@ -47,3 +79,16 @@ bool FirmwareUpdate::OnButtonPushed() {
   running = false;
   return true;
 }
+
+void FirmwareUpdate::UpdateValidated() {
+  lv_label_set_recolor(percentLabel, true);
+  lv_label_set_text(percentLabel, "#00ff00 Image Ok!#");
+}
+
+void FirmwareUpdate::UpdateError() {
+  lv_label_set_recolor(percentLabel, true);
+  lv_label_set_text(percentLabel, "#ff0000 Error!#");
+
+  lv_obj_set_hidden(labelBtn, false);
+  lv_obj_set_hidden(button, false);
+}

src/DisplayApp/Screens/FirmwareUpdate.h

@@ -26,13 +26,22 @@ namespace Pinetime {
           bool OnButtonPushed() override;
 
         private:
+          enum class States { Idle, Running, Validated, Error };
           Pinetime::Controllers::Ble& bleController;
-          lv_obj_t * bar1;
-          lv_obj_t * percentLabel;
-          lv_obj_t * titleLabel;
-          char percentStr[10];
+          lv_obj_t* bar1;
+          lv_obj_t* percentLabel;
+          lv_obj_t* titleLabel;
+          lv_obj_t* labelBtn;
+          lv_obj_t* button;
+          mutable char percentStr[10];
           bool running = true;
+          States state;
 
+          bool DisplayProgression() const;
+
+          void UpdateValidated();
+
+          void UpdateError();
       };
     }
   }