feat(xml): add lv_xml_set_default_asset_path (#8549)

src/core/lv_global.h

@@ -259,6 +259,10 @@ typedef struct _lv_global_t {
     lv_evdev_discovery_t * evdev_discovery;
 #endif
 
+#if LV_USE_XML
+    const char * xml_path_prefix;
+#endif
+
     void * user_data;
 } lv_global_t;
 

src/lv_init.c

@@ -511,8 +511,8 @@ void lv_deinit(void)
     lv_objid_builtin_destroy();
 #endif
 
-#if LV_USE_XML && LV_USE_TEST
-    lv_xml_test_unregister();
+#if LV_USE_XML
+    lv_xml_deinit();
 #endif
 
 #if LV_USE_TRANSLATION

src/others/xml/lv_xml.c

@@ -42,10 +42,12 @@
 #include "parsers/lv_xml_calendar_parser.h"
 #include "../../libs/expat/expat.h"
 #include "../../draw/lv_draw_image.h"
+#include "../../core/lv_global.h"
 
 /*********************
  *      DEFINES
  *********************/
+#define xml_path_prefix LV_GLOBAL_DEFAULT()->xml_path_prefix
 
 /**********************
  *      TYPEDEFS
@@ -71,6 +73,8 @@ static void view_end_element_handler(void * user_data, const char * name);
 
 void lv_xml_init(void)
 {
+    xml_path_prefix = lv_strdup("");
+
     lv_xml_component_init();
 
     lv_xml_register_font(NULL, "lv_font_default", lv_font_get_default());
@@ -142,6 +146,15 @@ void lv_xml_init(void)
     lv_xml_widget_register("lv_obj-bind_state_if_le", lv_obj_xml_bind_state_create, lv_obj_xml_bind_state_apply);
 }
 
+void lv_xml_deinit(void)
+{
+#if LV_USE_TEST
+    lv_xml_test_unregister();
+#endif
+
+    lv_free((void *)xml_path_prefix);
+}
+
 void * lv_xml_create_in_scope(lv_obj_t * parent, lv_xml_component_scope_t * parent_scope,
                               lv_xml_component_scope_t * scope,
                               const char ** attrs)
@@ -264,6 +277,15 @@ void * lv_xml_create(lv_obj_t * parent, const char * name, const char ** attrs)
     return NULL;
 }
 
+
+void lv_xml_set_default_asset_path(const char * path_prefix)
+{
+    lv_free((void *)xml_path_prefix);
+    if(path_prefix == NULL) path_prefix = "";
+    xml_path_prefix = lv_strdup(path_prefix);
+}
+
+
 lv_result_t lv_xml_register_font(lv_xml_component_scope_t * scope, const char * name, const lv_font_t * font)
 {
 
@@ -433,7 +455,9 @@ lv_result_t lv_xml_register_image(lv_xml_component_scope_t * scope, const char *
     lv_memzero(img, sizeof(*img));
     img->name = lv_strdup(name);
     if(lv_image_src_get_type(src) == LV_IMAGE_SRC_FILE) {
-        img->src = lv_strdup(src);
+        char buf[LV_XML_MAX_PATH_LENGTH];
+        lv_snprintf(buf, sizeof(buf), "%s%s", xml_path_prefix, src);
+        img->src = lv_strdup(buf);
     }
     else {
         img->src = src;

src/others/xml/lv_xml.h

@@ -26,6 +26,8 @@ extern "C" {
  *      DEFINES
  *********************/
 
+#define LV_XML_MAX_PATH_LENGTH 256
+
 /**********************
  *      TYPEDEFS
  **********************/
@@ -36,12 +38,25 @@ extern "C" {
 
 void lv_xml_init(void);
 
+void lv_xml_deinit(void);
+
 void * lv_xml_create(lv_obj_t * parent, const char * name, const char ** attrs);
 
 void * lv_xml_create_in_scope(lv_obj_t * parent, lv_xml_component_scope_t * parent_ctx,
                               lv_xml_component_scope_t * scope,
                               const char ** attrs);
 
+/**
+ * Set a path to prefix the image and font file source paths.
+ *
+ * In globals.xml usually the source path is like "images/logo.png".
+ * But on the actual device it can be located at e.g. "A:ui/assets/images/logo.png".
+ * By setting "A:ui/assets/" the path set in the XML files will be prefixed accordingly.
+ *
+ * @param path_prefix   the path to be used as prefix
+ */
+void lv_xml_set_default_asset_path(const char * path_prefix);
+
 lv_result_t lv_xml_register_font(lv_xml_component_scope_t * scope, const char * name, const lv_font_t * font);
 
 const lv_font_t * lv_xml_get_font(lv_xml_component_scope_t * scope, const char * name);

src/others/xml/lv_xml_component.c

@@ -19,11 +19,13 @@
 #include "parsers/lv_xml_obj_parser.h"
 #include "../../libs/expat/expat.h"
 #include "../../misc/lv_fs.h"
+#include "../../core/lv_global.h"
 #include <string.h>
 
 /*********************
  *      DEFINES
  *********************/
+#define xml_path_prefix LV_GLOBAL_DEFAULT()->xml_path_prefix
 
 /**********************
  *      TYPEDEFS
@@ -63,7 +65,6 @@ void lv_xml_component_init(void)
 
     lv_xml_component_scope_init(global_scope);
     global_scope->name = lv_strdup("globals");
-
 }
 
 void lv_xml_component_scope_init(lv_xml_component_scope_t * scope)
@@ -350,6 +351,9 @@ static void process_font_element(lv_xml_parser_state_t * state, const char * typ
         return;
     }
 
+    char src_path_full[LV_XML_MAX_PATH_LENGTH];
+    lv_snprintf(src_path_full, sizeof(src_path_full), "%s%s", xml_path_prefix, src_path);
+
     lv_xml_font_t * f;
     LV_LL_READ(&state->scope.font_ll, f) {
         if(lv_streq(f->name, name)) {
@@ -366,7 +370,7 @@ static void process_font_element(lv_xml_parser_state_t * state, const char * typ
             return;
         }
 #if LV_TINY_TTF_FILE_SUPPORT
-        lv_font_t * font = lv_tiny_ttf_create_file(src_path, lv_xml_atoi(size));
+        lv_font_t * font = lv_tiny_ttf_create_file(src_path_full, lv_xml_atoi(size));
         if(font == NULL) {
             LV_LOG_WARN("Couldn't load  `%s` tiny_ttf font", name);
             return;
@@ -393,7 +397,7 @@ static void process_font_element(lv_xml_parser_state_t * state, const char * typ
 #endif
     }
     else if(lv_streq(type, "bin")) {
-        lv_font_t * font = lv_binfont_create(src_path);
+        lv_font_t * font = lv_binfont_create(src_path_full);
         if(font == NULL) {
             LV_LOG_WARN("Couldn't load `%s` bin font", name);
             return;