1 #include "../lv_examples.h"
2 #if LV_BUILD_EXAMPLES
3
4 static lv_obj_t * panel;
5 static lv_obj_t * save_button;
6 static lv_obj_t * restore_button;
7 static int saved_scroll_x;
8 static int saved_scroll_y;
9
10 static void scroll_update_cb(lv_event_t * e);
11 static void button_event_cb(lv_event_t * e);
12
scroll_update_cb(lv_event_t * e)13 static void scroll_update_cb(lv_event_t * e)
14 {
15 LV_UNUSED(e);
16
17 LV_LOG("scroll info: x:%3"LV_PRId32", y:%3"LV_PRId32", top:%3"LV_PRId32", "
18 "bottom:%3"LV_PRId32", left:%3"LV_PRId32", right:%3"LV_PRId32"\n",
19 lv_obj_get_scroll_x(panel),
20 lv_obj_get_scroll_y(panel),
21 lv_obj_get_scroll_top(panel),
22 lv_obj_get_scroll_bottom(panel),
23 lv_obj_get_scroll_left(panel),
24 lv_obj_get_scroll_right(panel)
25 );
26 }
27
button_event_cb(lv_event_t * e)28 static void button_event_cb(lv_event_t * e)
29 {
30 lv_obj_t * obj = lv_event_get_target_obj(e);
31
32 if(obj == save_button) {
33 saved_scroll_x = lv_obj_get_scroll_x(panel);
34 saved_scroll_y = lv_obj_get_scroll_y(panel);
35 }
36 else {
37 lv_obj_scroll_to(panel, saved_scroll_x, saved_scroll_y, LV_ANIM_ON);
38 }
39 }
40
41 /**
42 * Demonstrate how scrolling appears automatically
43 */
lv_example_scroll_1(void)44 void lv_example_scroll_1(void)
45 {
46 /*Create an object with the new style*/
47 lv_obj_t * scr;
48 scr = lv_screen_active();
49 panel = lv_obj_create(scr);
50 lv_obj_set_size(panel, 200, 200);
51 lv_obj_align(panel, LV_ALIGN_CENTER, 44, 0);
52
53 lv_obj_t * child;
54 lv_obj_t * label;
55
56 child = lv_obj_create(panel);
57 lv_obj_set_pos(child, 0, 0);
58 lv_obj_set_size(child, 70, 70);
59 label = lv_label_create(child);
60 lv_label_set_text(label, "Zero");
61 lv_obj_center(label);
62
63 child = lv_obj_create(panel);
64 lv_obj_set_pos(child, 160, 80);
65 lv_obj_set_size(child, 80, 80);
66
67 lv_obj_t * child2 = lv_button_create(child);
68 lv_obj_set_size(child2, 100, 50);
69
70 label = lv_label_create(child2);
71 lv_label_set_text(label, "Right");
72 lv_obj_center(label);
73
74 child = lv_obj_create(panel);
75 lv_obj_set_pos(child, 40, 160);
76 lv_obj_set_size(child, 100, 70);
77 label = lv_label_create(child);
78 lv_label_set_text(label, "Bottom");
79 lv_obj_center(label);
80
81 /* When LV_OBJ_FLAG_SCROLL_ELASTIC is cleared, scrolling does not go past edge bounaries. */
82 /* lv_obj_clear_flag(panel, LV_OBJ_FLAG_SCROLL_ELASTIC); */
83
84 /* Call `scroll_update_cb` while panel is being scrolled. */
85 lv_obj_add_event_cb(panel, scroll_update_cb, LV_EVENT_SCROLL, NULL);
86
87 /* Set up buttons that save and restore scroll position. */
88 save_button = lv_button_create(scr);
89 restore_button = lv_button_create(scr);
90 lv_obj_t * lbl;
91 lbl = lv_label_create(save_button);
92 lv_label_set_text_static(lbl, "Save");
93 lbl = lv_label_create(restore_button);
94 lv_label_set_text_static(lbl, "Restore");
95 lv_obj_align_to(save_button, panel, LV_ALIGN_OUT_LEFT_MID, -10, -20);
96 lv_obj_align_to(restore_button, panel, LV_ALIGN_OUT_LEFT_MID, -10, 20);
97 lv_obj_add_event_cb(save_button, button_event_cb, LV_EVENT_CLICKED, NULL);
98 lv_obj_add_event_cb(restore_button, button_event_cb, LV_EVENT_CLICKED, NULL);
99 }
100
101 #endif
102
