1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
.. _lv_scale:
================
Scale (lv_scale)
================
Overview
********
Scale allows you to have a linear scale with ranges and sections with custom styling.
.. _lv_scale_parts_and_styles:
Parts and Styles
****************
The scale widget is divided in the following three parts:
- :cpp:enumerator:`LV_PART_MAIN` Main line. See blue line in the example image.
- :cpp:enumerator:`LV_PART_ITEMS` Minor ticks. See red minor ticks in the example image.
- :cpp:enumerator:`LV_PART_INDICATOR` Major ticks and its labels (if enabled).
See pink labels and green major ticks in the example image.
.. image:: /misc/scale.png
.. _lv_scale_usage:
Usage
*****
Set ranges
----------
The minor and major range (values of each tick) are configured with :cpp:expr:`lv_scale_set_range(scale, minor_range, major_range)`.
Configure ticks
---------------
Set the number of total ticks with :cpp:expr:`lv_scale_set_total_tick_count(scale, total_tick_count)`
and then configure the major tick being every Nth ticks with :cpp:expr:`lv_scale_set_major_tick_every(scale, nth_tick)`.
Labels on major ticks can be configured with :cpp:expr:`lv_scale_set_label_show(scale, show_label)`,
set `show_label` to true if labels should be drawn, :cpp:expr:`false` to hide them.
If instead of a numerical value in the major ticks a text is required they can be set
with :cpp:expr:`lv_scale_set_text_src(scale, custom_labels)` using ``NULL`` as the last element,
i.e. :cpp:expr:`static char * custom_labels[3] = {"One", "Two", NULL};`.
The length of the ticks can be configured with the length style property on the :cpp:enumerator:`LV_PART_INDICATOR`
for major ticks and :cpp:enumerator:`LV_PART_ITEMS` for minor ticks, for example with local style:
:cpp:expr:`lv_obj_set_style_length(scale, 5, LV_PART_INDICATOR);` for major ticks
and :cpp:expr:`lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);` for minor ticks.
Sections
--------
A section is the space between a minor and a major range. They can be created with :cpp:expr:`lv_scale_add_section(scale)`
and it handles back an :cpp:type:`lv_scale_section_t` pointer.
The range of the section is configured with :cpp:expr:`lv_scale_section_set_range(section, minor_range, major_range)`.
The style of each of the three parts of the scale section can be set with
:cpp:expr:`lv_scale_section_set_style(section, PART, style_pointer)`, where `PART` can be
:cpp:enumerator:`LV_PART_MAIN`, :cpp:enumerator:`LV_PART_ITEMS` or :cpp:enumerator:`LV_PART_INDICATOR`,
:cpp:expr:`style_pointer` should point to a global or static :cpp:type:`lv_style_t` variable.
For labels the following properties can be configured:
:cpp:func:`lv_style_set_text_font`, :cpp:func:`lv_style_set_text_color`,
:cpp:func:`lv_style_set_text_letter_space`, :cpp:func:`lv_style_set_text_opa`.
For lines (main line, major and minor ticks) the following properties can be configured:
:cpp:func:`lv_style_set_line_color`, :cpp:func:`lv_style_set_line_width`.
.. _lv_scale_events:
Events
******
No events supported by this widget.
.. _lv_scale_keys:
Keys
****
No keys supported by this widget.
.. _lv_scale_example:
Example
*******
.. include:: ../examples/widgets/scale/index.rst
.. _lv_scale_api:
API
***
:ref:`lv_scale`
|
