add multi language support system + lv_label_set_text_multi

lv_conf_templ.h

@@ -121,6 +121,7 @@
 #define USE_LV_GPU              1               /*1: Enable GPU interface*/
 #define USE_LV_REAL_DRAW        1               /*1: Enable function which draw directly to the frame buffer instead of VDB (required if LV_VDB_SIZE = 0)*/
 #define USE_LV_FILESYSTEM       1               /*1: Enable file system (might be required for images*/
+#define USE_LV_MULTI_LANG       0               /* Number of languages for labels to store (0: to disable this feature)*/
 
 /*Compiler settings*/
 #define LV_ATTRIBUTE_TICK_INC                   /* Define a custom attribute to `lv_tick_inc` function */

lv_core/lv_obj.c

@@ -35,6 +35,7 @@
  **********************/
 static void refresh_childen_position(lv_obj_t * obj, lv_coord_t x_diff, lv_coord_t y_diff);
 static void report_style_mod_core(void * style_p, lv_obj_t * obj);
+static void lang_set_core(lv_obj_t * obj);
 static void refresh_childen_style(lv_obj_t * obj);
 static void delete_children(lv_obj_t * obj);
 static bool lv_obj_design(lv_obj_t * obj, const  lv_area_t * mask_p, lv_design_mode_t mode);
@@ -48,6 +49,9 @@ static lv_obj_t * act_scr = NULL;
 static lv_obj_t * top_layer = NULL;
 static lv_obj_t * sys_layer = NULL;
 static lv_ll_t scr_ll;                 /*Linked list of screens*/
+#if USE_LV_MULTI_LANG
+static uint8_t lang_act = 0;
+#endif
 
 /**********************
  *      MACROS
@@ -456,6 +460,33 @@ void lv_scr_load(lv_obj_t * scr)
     lv_obj_invalidate(act_scr);
 }
 
+/*--------------
+ * Language
+ *--------------*/
+
+/**
+ * Change the language
+ * @param lang_id the id of the
+ */
+void lv_lang_set(uint8_t lang_id)
+{
+#if USE_LV_MULTI_LANG
+    lang_act = lang_id;
+
+    lv_obj_t * i;
+    LL_READ(scr_ll, i) {
+        i->signal_func(i, LV_SIGNAL_LANG_CHG, NULL);
+
+        lang_set_core(i);
+    }
+#else
+    LV_LOG_WARN("lv_lang_act: multiple languages are not enabled. See lv_conf.h USE_LV_MULTI_LANG ")
+    return 0;
+#endif
+
+
+}
+
 /*--------------------
  * Parent/children set
  *--------------------*/
@@ -1287,6 +1318,24 @@ void lv_obj_animate(lv_obj_t * obj, lv_anim_builtin_t type, uint16_t time, uint1
  * Getter functions
  *======================*/
 
+/*--------------
+ * Language
+ *--------------*/
+
+/**
+ * Return with ID of the currently selected language
+ * @return pointer to the active screen object (loaded by 'lv_scr_load()')
+ */
+lv_obj_t * lv_lang_act(void)
+{
+#if USE_LV_MULTI_LANG
+    return lang_act;
+#else
+    LV_LOG_WARN("lv_lang_act: multiple languages are not enabled. See lv_conf.h USE_LV_MULTI_LANG ")
+    return 0;
+#endif
+}
+
 /*------------------
  * Screen get
  *-----------------*/
@@ -1891,6 +1940,20 @@ static void report_style_mod_core(void * style_p, lv_obj_t * obj)
 }
 
 
+/**
+ * Change the language of the children. (Called recursively)
+ * @param obj pointer to an object
+ */
+static void lang_set_core(lv_obj_t * obj)
+{
+    lv_obj_t * i;
+    LL_READ(obj->child_ll, i) {
+        i->signal_func(i, LV_SIGNAL_LANG_CHG, NULL);
+
+        lang_set_core(i);
+    }
+}
+
 /**
  * Recursively refresh the style of the children. Go deeper until a not NULL style is found
  * because the NULL styles are inherited from the parent

lv_core/lv_obj.h

@@ -90,6 +90,7 @@ enum
     LV_SIGNAL_CORD_CHG,
     LV_SIGNAL_STYLE_CHG,
     LV_SIGNAL_REFR_EXT_SIZE,
+    LV_SIGNAL_LANG_CHG,
     LV_SIGNAL_GET_TYPE,
 
 	_LV_SIGNAL_FEEDBACK_SECTION_START,
@@ -550,6 +551,16 @@ void lv_obj_animate(lv_obj_t * obj, lv_anim_builtin_t type, uint16_t time, uint1
  * Getter functions
  *======================*/
 
+/*--------------
+ * Language
+ *--------------*/
+
+/**
+ * Return with ID of the currently selected language
+ * @return pointer to the active screen object (loaded by 'lv_scr_load()')
+ */
+lv_obj_t * lv_lang_act(void);
+
 /*------------------
  * Screen get
  *-----------------*/

lv_objx/lv_label.c

@@ -175,6 +175,7 @@ void lv_label_set_text(lv_obj_t * label, const char * text)
 
     lv_label_refr_text(label);
 }
+
 /**
  * Set a new text for a label from a character array. The array don't has to be '\0' terminated.
  * Memory will be allocated to store the array by the label.
@@ -232,6 +233,27 @@ void lv_label_set_static_text(lv_obj_t * label, const char * text)
     lv_label_refr_text(label);
 }
 
+/**
+ * Set the text for the multiple languages
+ * @param label pointer to a label object
+ * @param texts '\0' terminated character strings like `const char * txts[] = {"dog", "hund"}`.
+ *  The number of elements must be `USE_LV_MULTI_LANG`.
+ *  Only the pointer is saved so the variable must be global, static, or dynamically allocated.
+ *  NULL to disable multiple language for the label.
+ */
+void lv_label_set_text_multi(lv_obj_t * label, const char ** texts)
+{
+#if USE_LV_MULTI_LANG
+    lv_label_ext_t * ext = lv_obj_get_ext_attr(label);
+    ext->multi_lang_texts = texts;
+
+    /*Apply the new language*/
+    label->signal_func(label, LV_SIGNAL_LANG_CHG, NULL);
+#else
+    LV_LOG_WARN("lv_label_set_text_multi: multiple languages are not enabled. See lv_conf.h USE_LV_MULTI_LANG ")
+#endif
+}
+
 /**
  * Set the behavior of the label with longer text then the object size
  * @param label pointer to a label object
@@ -277,7 +299,6 @@ void lv_label_set_align(lv_obj_t * label, lv_label_align_t align)
     ext->align = align;
 
     lv_obj_invalidate(label);       /*Enough to invalidate because alignment is only drawing related (lv_refr_label_text() not required)*/
-
 }
 
 /**
@@ -345,6 +366,22 @@ char * lv_label_get_text(const lv_obj_t * label)
     return ext->text;
 }
 
+/**
+ * Get the array which stores the texts for multiple languages
+ * @param label pointer to a label object
+ * @return pointer to the array storing the texts. NULL if not specified.
+ */
+const char ** lv_label_get_text_multi(lv_obj_t * label)
+{
+#if USE_LV_MULTI_LANG
+    lv_label_ext_t * ext = lv_obj_get_ext_attr(label);
+    return ext->multi_lang_texts;
+#else
+    LV_LOG_WARN("lv_label_get_text_multi: multiple languages are not enabled. See lv_conf.h USE_LV_MULTI_LANG ")
+    return NULL;
+#endif
+
+}
 /**
  * Get the long mode of a label
  * @param label pointer to a label object
@@ -720,6 +757,12 @@ static lv_res_t lv_label_signal(lv_obj_t * label, lv_signal_t sign, void * param
             label->ext_size = LV_MATH_MAX(label->ext_size, style->body.padding.hor);
             label->ext_size = LV_MATH_MAX(label->ext_size, style->body.padding.ver);
         }
+    } else if(sign == LV_SIGNAL_LANG_CHG) {
+        if(ext->multi_lang_texts) {
+            uint8_t lang = lv_lang_act();
+            lv_label_set_text(label, ext->multi_lang_texts[lang]);
+        }
+
     } else if(sign == LV_SIGNAL_GET_TYPE) {
         lv_obj_type_t * buf = param;
         uint8_t i;

lv_objx/lv_label.h

@@ -61,16 +61,20 @@ typedef struct
 {
     /*Inherited from 'base_obj' so no inherited ext.*/  /*Ext. of ancestor*/
     /*New data for this type */
-    char * text;                     /*Text of the label*/
+    char * text;                            /*Text of the label*/
-    lv_label_long_mode_t long_mode; /*Determinate what to do with the long texts*/
+    lv_label_long_mode_t long_mode;         /*Determinate what to do with the long texts*/
 #if LV_TXT_UTF8 == 0
-    char dot_tmp[LV_LABEL_DOT_NUM + 1]; /*Store the character which are replaced by dots (Handled by the library)*/
+    char dot_tmp[LV_LABEL_DOT_NUM + 1];     /*Store the character which are replaced by dots (Handled by the library)*/
 #else
     char dot_tmp[LV_LABEL_DOT_NUM * 4 + 1]; /*Store the character which are replaced by dots (Handled by the library)*/
 #endif
+
+#if USE_LV_MULTI_LANG > 0
+    const char ** multi_lang_texts; /*Store multiple languages statically (only the pointer is saved)*/
+#endif
     uint16_t dot_end;               /*The text end position in dot mode (Handled by the library)*/
     uint16_t anim_speed;            /*Speed of scroll and roll animation in px/sec unit*/
-    lv_point_t offset;                 /*Text draw position offset*/
+    lv_point_t offset;              /*Text draw position offset*/
     uint8_t static_txt  :1;         /*Flag to indicate the text is static*/
     uint8_t align       :2;         /*Align type from 'lv_label_align_t'*/
     uint8_t recolor     :1;         /*Enable in-line letter re-coloring*/
@@ -119,6 +123,17 @@ void lv_label_set_array_text(lv_obj_t * label, const char * array, uint16_t size
  */
 void lv_label_set_static_text(lv_obj_t * label, const char * text);
 
+
+/**
+ * Set the text for the multiple languages
+ * @param label pointer to a label object
+ * @param texts '\0' terminated character strings like `const char * txts[] = {"dog", "hund"}`.
+ *  The number of elements must be `USE_LV_MULTI_LANG`.
+ *  Only the pointer is saved so the variable must be global, static, or dynamically allocated.
+ *  NULL to disable multiple language for the label.
+ */
+void lv_label_set_text_multi(lv_obj_t * label, const char ** texts);
+
 /**
  * Set the behavior of the label with longer text then the object size
  * @param label pointer to a label object
@@ -175,6 +190,13 @@ static inline void lv_label_set_style(lv_obj_t *label, lv_style_t *style)
  */
 char * lv_label_get_text(const lv_obj_t * label);
 
+/**
+ * Get the array which stores the texts for multiple languages
+ * @param label pointer to a label object
+ * @return pointer to the array storing the texts. NULL if not specified.
+ */
+const char ** lv_label_get_text_multi(lv_obj_t * label);
+
 /**
  * Get the long mode of a label
  * @param label pointer to a label object