FTXUI  5.0.0
C++ functional terminal UI.
hbox.cpp
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1 // Copyright 2020 Arthur Sonzogni. All rights reserved.
2 // Use of this source code is governed by the MIT license that can be found in
3 // the LICENSE file.
4 #include <algorithm> // for max
5 #include <cstddef> // for size_t
6 #include <memory> // for __shared_ptr_access, shared_ptr, make_shared, allocator_traits<>::value_type
7 #include <utility> // for move
8 #include <vector> // for vector, __alloc_traits<>::value_type
9 
10 #include "ftxui/dom/box_helper.hpp" // for Element, Compute
11 #include "ftxui/dom/elements.hpp" // for Element, Elements, hbox
12 #include "ftxui/dom/node.hpp" // for Node, Elements
13 #include "ftxui/dom/requirement.hpp" // for Requirement
14 #include "ftxui/screen/box.hpp" // for Box
15 
16 namespace ftxui {
17 
18 namespace {
19 class HBox : public Node {
20  public:
21  explicit HBox(Elements children) : Node(std::move(children)) {}
22 
23  void ComputeRequirement() override {
24  requirement_.min_x = 0;
25  requirement_.min_y = 0;
26  requirement_.flex_grow_x = 0;
27  requirement_.flex_grow_y = 0;
28  requirement_.flex_shrink_x = 0;
29  requirement_.flex_shrink_y = 0;
30  requirement_.selection = Requirement::NORMAL;
31  for (auto& child : children_) {
32  child->ComputeRequirement();
33  if (requirement_.selection < child->requirement().selection) {
34  requirement_.selection = child->requirement().selection;
35  requirement_.selected_box = child->requirement().selected_box;
36  requirement_.selected_box.x_min += requirement_.min_x;
37  requirement_.selected_box.x_max += requirement_.min_x;
38  }
39  requirement_.min_x += child->requirement().min_x;
40  requirement_.min_y =
41  std::max(requirement_.min_y, child->requirement().min_y);
42  }
43  }
44 
45  void SetBox(Box box) override {
46  Node::SetBox(box);
47 
48  std::vector<box_helper::Element> elements(children_.size());
49  for (size_t i = 0; i < children_.size(); ++i) {
50  auto& element = elements[i];
51  const auto& requirement = children_[i]->requirement();
52  element.min_size = requirement.min_x;
53  element.flex_grow = requirement.flex_grow_x;
54  element.flex_shrink = requirement.flex_shrink_x;
55  }
56  const int target_size = box.x_max - box.x_min + 1;
57  box_helper::Compute(&elements, target_size);
58 
59  int x = box.x_min;
60  for (size_t i = 0; i < children_.size(); ++i) {
61  box.x_min = x;
62  box.x_max = x + elements[i].size - 1;
63  children_[i]->SetBox(box);
64  x = box.x_max + 1;
65  }
66  }
67 };
68 
69 } // namespace
70 
71 /// @brief A container displaying elements horizontally one by one.
72 /// @param children The elements in the container
73 /// @return The container.
74 ///
75 /// #### Example
76 ///
77 /// ```cpp
78 /// hbox({
79 /// text("Left"),
80 /// text("Right"),
81 /// });
82 /// ```
83 Element hbox(Elements children) {
84  return std::make_shared<HBox>(std::move(children));
85 }
86 
87 } // namespace ftxui
virtual void SetBox(Box box)
Assign a position and a dimension to an element for drawing.
Definition: node.cpp:26
void Compute(std::vector< Element > *elements, int target_size)
Definition: box_helper.cpp:64
std::shared_ptr< Node > Element
Definition: elements.hpp:23
Element hbox(Elements)
A container displaying elements horizontally one by one.
Definition: hbox.cpp:83
std::vector< Element > Elements
Definition: elements.hpp:24