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Description
What MCU/Processor/Board and compiler are you using?
Linux
What LVGL version are you using?
lvglV8.3.0
What do you want to achieve?
scroll_to_y to set the custom roller be set to index 0
What have you tried so far?
I design a custom roller ，it can scroll to other index insted of 0 ，1，28，29…（there are the first、second One）
Code to reproduce
Add a code snippet which can run in the simulator. It should contain only the relevant code that compiles without errors when separated from your main code base.
The code block(s) should be formatted like:
//created by Sean on 2024.1.2
//实现基础的自定义roller样式,其他效果需自行实现
#include "view.h"
typedef struct scrollParam
{
int step;
int first_y;
int selectindex;
}scrollParam_t;
static void scroll_event(lv_event_t * e)
{
lv_obj_t * scroll_container = lv_event_get_target(e); // 获取事件的初始对象
scrollParam_t *param = (scrollParam_t*)e->user_data;
lv_coord_t scroll_y = lv_obj_get_scroll_y(scroll_container);
printf("scroll_y = %d \r\n",scroll_y);//看打印知道位置-100 -42 16 xxx(步进58)
//这个是get_selected
if ((scroll_y-(param->first_y))%param->step == 0) //选中项
{
param->selectindex = (scroll_y-(param->first_y))/param->step;//选中项
printf("param->selectindex = %d \r\n",param->selectindex);
}
for (int i = 0; i < lv_obj_get_child_cnt(scroll_container); i++) {
lv_obj_t * item = lv_obj_get_child(scroll_container, i);
lv_obj_t* label = lv_obj_get_child(lv_obj_get_child(scroll_container, i),0);
int child_scroll_y = i*param->step+(param->first_y);
//选中的样式
if ( scroll_y > child_scroll_y - param->step/2 && scroll_y < child_scroll_y + param->step/2) {
lv_obj_set_style_text_font(label,biz_fonts.ft_regular_60.font,0);
lv_obj_set_style_text_opa(label,255,0);
// printf("1 = %d \r\n",lv_obj_get_y(label));//10
// lv_obj_set_y(label,10);
lv_obj_set_align(label,LV_ALIGN_CENTER);
}
else if ( scroll_y > child_scroll_y - param->step/2 - param->step && scroll_y < child_scroll_y + param->step/2 + param->step) {
lv_obj_set_style_text_font(label,biz_fonts.ft_regular_36.font,0);
lv_obj_set_style_text_opa(label,200,0);
// printf("2 = %d \r\n",lv_obj_get_y(label));//24
// lv_obj_set_y(label,24);
lv_obj_set_align(label,LV_ALIGN_CENTER);
}
else //非选中样式
{
lv_obj_set_style_text_font(label,biz_fonts.ft_regular_18.font,0);
lv_obj_set_style_text_opa(label,150,0);
// printf("3 = %d \r\n",lv_obj_get_y(label));//35
if (i < param->selectindex)
lv_obj_set_align(label,LV_ALIGN_BOTTOM_MID);
else
lv_obj_set_align(label,LV_ALIGN_TOP_MID);
}
}
}
lv_obj_t *view_custom_roller_create(lv_obj_t *parent,uint16_t width,uint16_t height,uint16_t num,uint16_t visable_sum)
{
lv_obj_t *container = lv_obj_create(parent);
lv_obj_style_clean(container);//clean后设置bg color等style属性就会无效了
// lv_obj_set_style_border_width(container,0,0);
// lv_obj_set_style_bg_color(container,lv_color_hex(0x000000), 0);
lv_obj_add_flag(container,LV_OBJ_FLAG_SCROLLABLE);
lv_obj_set_scrollbar_mode(container, LV_SCROLLBAR_MODE_OFF);
lv_obj_set_flex_flow(container, LV_FLEX_FLOW_COLUMN);
//改父对象和子对象的size来实现visable
lv_obj_set_size(container,width,height);
lv_obj_set_scroll_snap_y(container, LV_SCROLL_SNAP_CENTER);
for (size_t i = 0; i < num; i++)
{
lv_obj_t *child = lv_obj_create(container);
lv_obj_style_clean(child);
lv_obj_set_height(child,height/visable_sum);
lv_obj_t *label = lv_label_create(child);
lv_obj_center(label);
lv_label_set_text_fmt(label, "%d",i);
lv_obj_set_style_text_color(label,lv_color_hex(0xffffff),0);
lv_obj_set_style_text_align(label, LV_TEXT_ALIGN_CENTER, 0);
lv_obj_set_style_text_font(label,biz_fonts.ft_regular_18.font,0);
}
container->user_data = (scrollParam_t*)malloc(sizeof(scrollParam_t));
((scrollParam_t*)(container->user_data))->step = height/visable_sum+8;
((scrollParam_t*)(container->user_data))->first_y = 0 - (visable_sum/2)*(height/visable_sum);
// printf(" ((scrollParam_t*)(container->user_data))->step = %d , ((scrollParam_t*)(container->user_data))->y = %d \r\n", ((scrollParam_t*)(container->user_data))->step, ((scrollParam_t*)(container->user_data))->first_y);
lv_obj_add_event_cb(container,scroll_event, LV_EVENT_SCROLL, container->user_data);
//手动snap初始化
lv_obj_update_snap(container,LV_ANIM_OFF);
return container;
}
int view_custom_roller_get_selected(lv_obj_t *des)
{
return ((scrollParam_t*)(des->user_data))->selectindex;
}
void view_custom_roller_set_selected(lv_obj_t *des,uint16_t index,lv_anim_enable_t anim_en)
{
int pos = index*(((scrollParam_t*)(des->user_data))->step)+((((scrollParam_t*)(des->user_data))->first_y));
printf("pos = %d step=%d firsty=%d \r\n",pos,(((scrollParam_t*)(des->user_data))->step),(((scrollParam_t*)(des->user_data))->first_y));
lv_obj_scroll_to_y(des,pos,anim_en);
//sean 现在仍然有bug,没法滚到前2个/后2个,需定位什么原因
}
I use this in main(),view_custom_roller_set_selected(_holder->custom_roller,5,LV_ANIM_ON);is okay,
but when I view_custom_roller_set_selected(_holder->custom_roller,0/1/29/30,LV_ANIM_ON);
scroll_to_y doesn't work,please tell me how to deal it~
{
_holder->custom_roller = view_custom_roller_create(_layout,200,450,30,5);
view_custom_roller_set_selected(_holder->custom_roller,0,LV_ANIM_ON);
}
Screenshot and/or video
If possible, add screenshots and/or videos about the current state.
