[LVGL] 可点击的文字label

news2024/12/25 12:14:44

LVGL8.x 自带的label 是没有点击响应的功能，即使加了lv_obj_add_event_cb 也不起作用，为了解决这个问题，我们使用了按钮控件去模拟纯label的效果；有了这个demo用户就可以实现类似超链接点击一个文字就跳转到某个页面的功能。

static void tp_event_handler(lv_event_t * e)
{
    lv_event_code_t code = lv_event_get_code(e);
    uint8_t* btn_id = e->user_data;
   
    if(code == LV_EVENT_CLICKED) {
        printf("[Click] btn_id = %d \n",*btn_id);
    }
    else if(code == LV_EVENT_VALUE_CHANGED) {
        printf("[Toggle] btn_id = %d \n",*btn_id);
    }
}

typedef struct
{
    uint8_t txt_id;
    int x;
    int y;
    char* txt_str;       
    void(*event_handler)(lv_event_t* e);
    lv_obj_t* self_obj;

} QUI_TXT;

#define NUM_OBJ  (5)
static QUI_TXT lqui_txt[NUM_OBJ]=
{
    {0,50,30,"China",tp_event_handler,NULL},
    {1,50,60,"England",tp_event_handler,NULL},
    {2,50,90,"Brazil",tp_event_handler,NULL},
    {3,50,120,"Mexico",tp_event_handler,NULL},
    {4,50,150,"Egypt",tp_event_handler,NULL},
};

static int create_tp_txt(lv_obj_t* parent_obj,QUI_TXT* qTxt)
{
    lv_obj_t* btn = lv_btn_create(parent_obj);
    if (btn==NULL)
    {
        return 0;
    }
    lv_obj_set_style_bg_opa(btn, 0, 0);
    lv_obj_set_style_shadow_opa(btn, 0, 0); 
    lv_obj_set_style_text_color(btn, lv_color_hex(0x000000), 0);
    lv_obj_set_pos(btn, qTxt->x,qTxt->y);

    lv_obj_t* label = lv_label_create(btn);  
    if (qTxt->txt_str)
    {
        lv_label_set_text(label,qTxt->txt_str);
    }
    if (qTxt->event_handler != NULL)
    {
        lv_obj_add_event_cb(btn, qTxt->event_handler, LV_EVENT_ALL, (void*)&qTxt->txt_id);
    }
    qTxt->self_obj = btn;
    return 1;
}


void lv_example_tp_text(void)
{
    lv_obj_t* parent_obj = lv_scr_act();
    for(int i=0;i< NUM_OBJ;i++)
        create_tp_txt(parent_obj, &lqui_txt[i]);

    lv_obj_add_flag(lqui_txt[0].self_obj,LV_OBJ_FLAG_CHECKABLE);//按钮1做特殊效果

    lv_timer_handler(); 
    return;
}