Fix LVGL_UI G-code preview (#20564)

Marlin/src/lcd/extui/lib/mks_ui/draw_print_file.cpp

@@ -298,8 +298,8 @@ void disp_gcode_icon(uint8_t file_num) {
           strcat(test_public_buf_l, list_file.file_name[i]);
           char *temp = strstr(test_public_buf_l, ".GCO");
           if (temp) strcpy(temp, ".bin");
-          lv_obj_set_event_cb_mks(buttonGcode[i], event_handler, (i + 1), "", 0);
+          lv_obj_set_event_cb_mks(buttonGcode[i], event_handler, (i + 1), test_public_buf_l, 0);
-          lv_imgbtn_set_src_both(buttonGcode[i], test_public_buf_l);
+          lv_imgbtn_set_src_both(buttonGcode[i], buttonGcode[i]->mks_pic_name);
           if (i < 3) {
             lv_obj_set_pos(buttonGcode[i], BTN_X_PIXEL * i + INTERVAL_V * (i + 1) + FILE_PRE_PIC_X_OFFSET, titleHeight + FILE_PRE_PIC_Y_OFFSET);
             buttonText[i] = lv_btn_create(scr, nullptr);
@@ -358,7 +358,7 @@ void disp_gcode_icon(uint8_t file_num) {
 uint32_t lv_open_gcode_file(char *path) {
   #if ENABLED(SDSUPPORT)
     uint32_t *ps4;
-    uint32_t pre_sread_cnt = 0;
+    uint32_t pre_sread_cnt = UINT32_MAX;
     char *cur_name;
 
     cur_name = strrchr(path, '/');
@@ -399,6 +399,7 @@ void lv_gcode_file_read(uint8_t *data_buf) {
     char temp_test[200];
     volatile uint16_t *p_index;
 
+    watchdog_refresh();
     memset(public_buf, 0, 200);
 
     while (card.isFileOpen()) {
@@ -418,7 +419,7 @@ void lv_gcode_file_read(uint8_t *data_buf) {
       uint16_t c = card.get();
       // check if we have more data or finished the line (CR)
       if (c == '\r') break;
-      card.setIndex(card.getIndex());
+      card.setIndex(card.getIndex() - 1);
       k++;
       j = 0;
       ignore_start = false;

Marlin/src/lcd/extui/lib/mks_ui/tft_lvgl_configuration.cpp

@@ -380,7 +380,7 @@ lv_fs_res_t sd_open_cb (lv_fs_drv_t * drv, void * file_p, const char * path, lv_
   if (temp) strcpy(temp, ".GCO");
   sd_read_base_addr = lv_open_gcode_file((char *)name_buf);
   sd_read_addr_offset = sd_read_base_addr;
-  if (sd_read_addr_offset == 0) return LV_FS_RES_NOT_EX;
+  if (sd_read_addr_offset == UINT32_MAX) return LV_FS_RES_NOT_EX;
   return LV_FS_RES_OK;
 }