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
|
#include "linear_layout.h"
namespace cru::ui::controls
{
LinearLayout::LinearLayout(const Orientation orientation)
: Control(true), orientation_(orientation)
{
}
Size LinearLayout::OnMeasure(const Size& available_size)
{
const auto layout_params = GetLayoutParams();
if (!layout_params->Validate())
throw std::runtime_error("LayoutParams is not valid. Please check it.");
auto&& get_available_length_for_child = [](const MeasureLength& layout_length, const float available_length) -> float
{
switch (layout_length.mode)
{
case MeasureMode::Exactly:
{
return std::min(layout_length.length, available_length);
}
case MeasureMode::Stretch:
case MeasureMode::Content:
{
return available_length;
}
default:
UnreachableCode();
}
};
Size total_available_size_for_children(
get_available_length_for_child(layout_params->width, available_size.width),
get_available_length_for_child(layout_params->height, available_size.height)
);
auto rest_available_size_for_children = total_available_size_for_children;
ForeachChild([this, &rest_available_size_for_children](Control* const control)
{
control->Measure(rest_available_size_for_children);
if (orientation_ == Orientation::Horizontal)
{
rest_available_size_for_children.width -= control->GetDesiredSize().width;
if (rest_available_size_for_children.width < 0)
rest_available_size_for_children.width = 0;
}
else
{
rest_available_size_for_children.height -= control->GetDesiredSize().height;
if (rest_available_size_for_children.height < 0)
rest_available_size_for_children.height = 0;
}
});
auto actual_size_for_children = total_available_size_for_children - rest_available_size_for_children;
auto&& calculate_final_length = [](const MeasureLength& layout_length, const float length_for_children, const float max_child_length) -> float
{
switch (layout_length.mode)
{
case MeasureMode::Exactly:
case MeasureMode::Stretch:
return length_for_children;
case MeasureMode::Content:
return max_child_length;
default:
UnreachableCode();
}
};
return Size(
calculate_final_length(layout_params->width, total_available_size_for_children.width, actual_size_for_children.width),
calculate_final_length(layout_params->height, total_available_size_for_children.height, actual_size_for_children.height)
);
}
void LinearLayout::OnLayout(const Rect& rect)
{
auto current_anchor = Point::zero;
ForeachChild([this, ¤t_anchor](Control* control)
{
const auto size = control->GetDesiredSize();
control->Layout(Rect(current_anchor, size));
if (orientation_ == Orientation::Horizontal)
current_anchor.x += size.width;
else
current_anchor.y += size.height;
});
}
}
|
