lvgl/examples/scroll/lv_example_scroll_1.c

102 lines
3.1 KiB
C

#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
static lv_obj_t * panel;
static lv_obj_t * save_button;
static lv_obj_t * restore_button;
static int saved_scroll_x;
static int saved_scroll_y;
static void scroll_update_cb(lv_event_t * e);
static void button_event_cb(lv_event_t * e);
static void scroll_update_cb(lv_event_t * e)
{
LV_UNUSED(e);
LV_LOG("scroll info: x:%3"LV_PRId32", y:%3"LV_PRId32", top:%3"LV_PRId32", "
"bottom:%3"LV_PRId32", left:%3"LV_PRId32", right:%3"LV_PRId32"\n",
lv_obj_get_scroll_x(panel),
lv_obj_get_scroll_y(panel),
lv_obj_get_scroll_top(panel),
lv_obj_get_scroll_bottom(panel),
lv_obj_get_scroll_left(panel),
lv_obj_get_scroll_right(panel)
);
}
static void button_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target_obj(e);
if(obj == save_button) {
saved_scroll_x = lv_obj_get_scroll_x(panel);
saved_scroll_y = lv_obj_get_scroll_y(panel);
}
else {
lv_obj_scroll_to(panel, saved_scroll_x, saved_scroll_y, LV_ANIM_ON);
}
}
/**
* Demonstrate how scrolling appears automatically
*/
void lv_example_scroll_1(void)
{
/*Create an object with the new style*/
lv_obj_t * scr;
scr = lv_screen_active();
panel = lv_obj_create(scr);
lv_obj_set_size(panel, 200, 200);
lv_obj_align(panel, LV_ALIGN_CENTER, 44, 0);
lv_obj_t * child;
lv_obj_t * label;
child = lv_obj_create(panel);
lv_obj_set_pos(child, 0, 0);
lv_obj_set_size(child, 70, 70);
label = lv_label_create(child);
lv_label_set_text(label, "Zero");
lv_obj_center(label);
child = lv_obj_create(panel);
lv_obj_set_pos(child, 160, 80);
lv_obj_set_size(child, 80, 80);
lv_obj_t * child2 = lv_button_create(child);
lv_obj_set_size(child2, 100, 50);
label = lv_label_create(child2);
lv_label_set_text(label, "Right");
lv_obj_center(label);
child = lv_obj_create(panel);
lv_obj_set_pos(child, 40, 160);
lv_obj_set_size(child, 100, 70);
label = lv_label_create(child);
lv_label_set_text(label, "Bottom");
lv_obj_center(label);
/* When LV_OBJ_FLAG_SCROLL_ELASTIC is cleared, scrolling does not go past edge bounaries. */
/* lv_obj_clear_flag(panel, LV_OBJ_FLAG_SCROLL_ELASTIC); */
/* Call `scroll_update_cb` while panel is being scrolled. */
lv_obj_add_event_cb(panel, scroll_update_cb, LV_EVENT_SCROLL, NULL);
/* Set up buttons that save and restore scroll position. */
save_button = lv_button_create(scr);
restore_button = lv_button_create(scr);
lv_obj_t * lbl;
lbl = lv_label_create(save_button);
lv_label_set_text_static(lbl, "Save");
lbl = lv_label_create(restore_button);
lv_label_set_text_static(lbl, "Restore");
lv_obj_align_to(save_button, panel, LV_ALIGN_OUT_LEFT_MID, -10, -20);
lv_obj_align_to(restore_button, panel, LV_ALIGN_OUT_LEFT_MID, -10, 20);
lv_obj_add_event_cb(save_button, button_event_cb, LV_EVENT_CLICKED, NULL);
lv_obj_add_event_cb(restore_button, button_event_cb, LV_EVENT_CLICKED, NULL);
}
#endif