diff --git a/CHANGELOG.md b/CHANGELOG.md
index 611187dc20527b5071d7f250f4982e00ebd69737..476b6336fde45eb391d0b224269e30f7f2eac3d2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -39,6 +39,8 @@ current (development)
component in its parent. See #932
- Feature: Add `EntryState::index`. This allows to get the index of a menu entry.
See #932
+- Feature: Add `SliderOption::on_change`. This allows to set a callback when the
+ slider value changes. See #938.
### Dom
- Feature: Add `hscroll_indicator`. It display an horizontal indicator
diff --git a/include/ftxui/component/component_options.hpp b/include/ftxui/component/component_options.hpp
index a55a4df842a9bc90c7ff66ff0991535e094c5dcd..e9dd0845365881dbc37d1d7b34ff6331bcb1cd33 100644
--- a/include/ftxui/component/component_options.hpp
+++ b/include/ftxui/component/component_options.hpp
@@ -228,6 +228,7 @@ struct SliderOption {
Direction direction = Direction::Right;
Color color_active = Color::White;
Color color_inactive = Color::GrayDark;
+ std::function<void()> on_change; ///> Called when `value` is updated.
};
// Parameter pack used by `WindowOptions::render`.
diff --git a/src/ftxui/component/slider.cpp b/src/ftxui/component/slider.cpp
index b1075805cab66c73c675594f2237aaf23f682125..e8efbb8576105b97f2da91f1a87e2bbe71c6c1aa 100644
--- a/src/ftxui/component/slider.cpp
+++ b/src/ftxui/component/slider.cpp
@@ -35,31 +35,26 @@ Decorator flexDirection(Direction direction) {
}
template <class T>
-class SliderBase : public ComponentBase {
+class SliderBase : public SliderOption<T>, public ComponentBase {
public:
- explicit SliderBase(SliderOption<T> options)
- : value_(options.value),
- min_(options.min),
- max_(options.max),
- increment_(options.increment),
- options_(options) {}
+ explicit SliderBase(SliderOption<T> options) : SliderOption<T>(options) {}
Element Render() override {
- auto gauge_color = Focused() ? color(options_.color_active)
- : color(options_.color_inactive);
- const float percent = float(value_() - min_()) / float(max_() - min_());
- return gaugeDirection(percent, options_.direction) |
- flexDirection(options_.direction) | reflect(gauge_box_) |
- gauge_color;
+ auto gauge_color =
+ Focused() ? color(this->color_active) : color(this->color_inactive);
+ const float percent =
+ float(this->value() - this->min()) / float(this->max() - this->min());
+ return gaugeDirection(percent, this->direction) |
+ flexDirection(this->direction) | reflect(gauge_box_) | gauge_color;
}
void OnLeft() {
- switch (options_.direction) {
+ switch (this->direction) {
case Direction::Right:
- value_() -= increment_();
+ this->value() -= this->increment();
break;
case Direction::Left:
- value_() += increment_();
+ this->value() += this->increment();
break;
case Direction::Up:
case Direction::Down:
@@ -68,12 +63,12 @@ class SliderBase : public ComponentBase {
}
void OnRight() {
- switch (options_.direction) {
+ switch (this->direction) {
case Direction::Right:
- value_() += increment_();
+ this->value() += this->increment();
break;
case Direction::Left:
- value_() -= increment_();
+ this->value() -= this->increment();
break;
case Direction::Up:
case Direction::Down:
@@ -82,12 +77,12 @@ class SliderBase : public ComponentBase {
}
void OnUp() {
- switch (options_.direction) {
+ switch (this->direction) {
case Direction::Up:
- value_() -= increment_();
+ this->value() -= this->increment();
break;
case Direction::Down:
- value_() += increment_();
+ this->value() += this->increment();
break;
case Direction::Left:
case Direction::Right:
@@ -96,12 +91,12 @@ class SliderBase : public ComponentBase {
}
void OnDown() {
- switch (options_.direction) {
+ switch (this->direction) {
case Direction::Down:
- value_() -= increment_();
+ this->value() += this->increment();
break;
case Direction::Up:
- value_() += increment_();
+ this->value() -= this->increment();
break;
case Direction::Left:
case Direction::Right:
@@ -114,7 +109,7 @@ class SliderBase : public ComponentBase {
return OnMouseEvent(event);
}
- T old_value = value_();
+ T old_value = this->value();
if (event == Event::ArrowLeft || event == Event::Character('h')) {
OnLeft();
}
@@ -128,8 +123,11 @@ class SliderBase : public ComponentBase {
OnUp();
}
- value_() = util::clamp(value_(), min_(), max_());
- if (old_value != value_()) {
+ this->value() = std::max(this->min(), std::min(this->max(), this->value()));
+ if (old_value != this->value()) {
+ if (this->on_change) {
+ this->on_change();
+ }
return true;
}
@@ -143,33 +141,45 @@ class SliderBase : public ComponentBase {
return true;
}
- switch (options_.direction) {
+ T old_value = this->value();
+ switch (this->direction) {
case Direction::Right: {
- value_() = min_() + (event.mouse().x - gauge_box_.x_min) *
- (max_() - min_()) /
- (gauge_box_.x_max - gauge_box_.x_min);
+ this->value() =
+ this->min() + (event.mouse().x - gauge_box_.x_min) *
+ (this->max() - this->min()) /
+ (gauge_box_.x_max - gauge_box_.x_min);
+
break;
}
case Direction::Left: {
- value_() = max_() - (event.mouse().x - gauge_box_.x_min) *
- (max_() - min_()) /
- (gauge_box_.x_max - gauge_box_.x_min);
+ this->value() =
+ this->max() - (event.mouse().x - gauge_box_.x_min) *
+ (this->max() - this->min()) /
+ (gauge_box_.x_max - gauge_box_.x_min);
break;
}
case Direction::Down: {
- value_() = min_() + (event.mouse().y - gauge_box_.y_min) *
- (max_() - min_()) /
- (gauge_box_.y_max - gauge_box_.y_min);
+ this->value() =
+ this->min() + (event.mouse().y - gauge_box_.y_min) *
+ (this->max() - this->min()) /
+ (gauge_box_.y_max - gauge_box_.y_min);
break;
}
case Direction::Up: {
- value_() = max_() - (event.mouse().y - gauge_box_.y_min) *
- (max_() - min_()) /
- (gauge_box_.y_max - gauge_box_.y_min);
+ this->value() =
+ this->max() - (event.mouse().y - gauge_box_.y_min) *
+ (this->max() - this->min()) /
+ (gauge_box_.y_max - gauge_box_.y_min);
break;
}
}
- value_() = std::max(min_(), std::min(max_(), value_()));
+
+ this->value() =
+ std::max(this->min(), std::min(this->max(), this->value()));
+
+ if (old_value != this->value() && this->on_change) {
+ this->on_change();
+ }
return true;
}
@@ -197,11 +207,6 @@ class SliderBase : public ComponentBase {
bool Focusable() const final { return true; }
private:
- Ref<T> value_;
- ConstRef<T> min_;
- ConstRef<T> max_;
- ConstRef<T> increment_;
- SliderOption<T> options_;
Box gauge_box_;
CapturedMouse captured_mouse_;
};
@@ -256,6 +261,7 @@ class SliderWithLabel : public ComponentBase {
Box box_;
bool mouse_hover_ = false;
};
+
} // namespace
/// @brief An horizontal slider.
@@ -340,6 +346,7 @@ template <typename T>
Component Slider(SliderOption<T> options) {
return Make<SliderBase<T>>(options);
}
+
template Component Slider(SliderOption<int8_t>);
template Component Slider(SliderOption<int16_t>);
template Component Slider(SliderOption<int32_t>);
diff --git a/src/ftxui/component/slider_test.cpp b/src/ftxui/component/slider_test.cpp
index c2057555726b0f78d7e0d8b4f4e37b14256dc34b..21b9656948a3495c043a04baf5c218a4db9572bc 100644
--- a/src/ftxui/component/slider_test.cpp
+++ b/src/ftxui/component/slider_test.cpp
@@ -45,6 +45,7 @@ Event MouseReleased(int x, int y) {
} // namespace
TEST(SliderTest, Right) {
+ int updated = 0;
int value = 50;
auto slider = Slider<int>({
.value = &value,
@@ -52,23 +53,31 @@ TEST(SliderTest, Right) {
.max = 100,
.increment = 10,
.direction = Direction::Right,
+ .on_change = [&]() { updated++; },
});
Screen screen(11, 1);
Render(screen, slider->Render());
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(3, 0)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(9, 0)));
EXPECT_EQ(value, 90);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(9, 2)));
EXPECT_EQ(value, 90);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(5, 2)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 2);
EXPECT_TRUE(slider->OnEvent(MouseReleased(5, 2)));
EXPECT_FALSE(slider->OnEvent(MousePressed(5, 2)));
+ EXPECT_EQ(value, 50);
}
TEST(SliderTest, Left) {
+ int updated = 0;
int value = 50;
auto slider = Slider<int>({
.value = &value,
@@ -76,23 +85,31 @@ TEST(SliderTest, Left) {
.max = 100,
.increment = 10,
.direction = Direction::Left,
+ .on_change = [&]() { updated++; },
});
Screen screen(11, 1);
Render(screen, slider->Render());
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(3, 0)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(9, 0)));
EXPECT_EQ(value, 10);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(9, 2)));
EXPECT_EQ(value, 10);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(5, 2)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 2);
EXPECT_TRUE(slider->OnEvent(MouseReleased(5, 2)));
EXPECT_FALSE(slider->OnEvent(MousePressed(5, 2)));
+ EXPECT_EQ(value, 50);
}
TEST(SliderTest, Down) {
+ int updated = 0;
int value = 50;
auto slider = Slider<int>({
.value = &value,
@@ -100,23 +117,32 @@ TEST(SliderTest, Down) {
.max = 100,
.increment = 10,
.direction = Direction::Down,
+ .on_change = [&]() { updated++; },
});
Screen screen(1, 11);
Render(screen, slider->Render());
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(0, 3)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(0, 9)));
EXPECT_EQ(value, 90);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(2, 9)));
EXPECT_EQ(value, 90);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(2, 5)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 2);
EXPECT_TRUE(slider->OnEvent(MouseReleased(2, 5)));
EXPECT_FALSE(slider->OnEvent(MousePressed(2, 5)));
+ EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 2);
}
TEST(SliderTest, Up) {
+ int updated = 0;
int value = 50;
auto slider = Slider<int>({
.value = &value,
@@ -124,20 +150,27 @@ TEST(SliderTest, Up) {
.max = 100,
.increment = 10,
.direction = Direction::Up,
+ .on_change = [&]() { updated++; },
});
Screen screen(1, 11);
Render(screen, slider->Render());
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(0, 3)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 0);
EXPECT_TRUE(slider->OnEvent(MousePressed(0, 9)));
EXPECT_EQ(value, 10);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(2, 9)));
EXPECT_EQ(value, 10);
+ EXPECT_EQ(updated, 1);
EXPECT_TRUE(slider->OnEvent(MousePressed(2, 5)));
EXPECT_EQ(value, 50);
+ EXPECT_EQ(updated, 2);
EXPECT_TRUE(slider->OnEvent(MouseReleased(2, 5)));
EXPECT_FALSE(slider->OnEvent(MousePressed(2, 5)));
+ EXPECT_EQ(value, 50);
}
TEST(SliderTest, Focus) {