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// #![warn(missing_docs)] use std::hash::Hash; use crate::{ color::*, containers::*, epaint::text::Fonts, layout::*, mutex::MutexGuard, placer::Placer, widgets::*, *, }; // ---------------------------------------------------------------------------- /// This is what you use to place widgets. /// /// Represents a region of the screen with a type of layout (horizontal or vertical). /// /// ``` /// # let mut ui = egui::Ui::__test(); /// ui.add(egui::Label::new("Hello World!")); /// ui.label("A shorter and more convenient way to add a label."); /// ui.horizontal(|ui| { /// ui.label("Add widgets"); /// if ui.button("on the same row!").clicked() { /// /* … */ /// } /// }); /// ``` pub struct Ui { /// ID of this ui. /// Generated based on id of parent ui together with /// another source of child identity (e.g. window title). /// Acts like a namespace for child uis. /// Should be unique and persist predictably from one frame to next /// so it can be used as a source for storing state (e.g. window position, or if a collapsing header is open). id: Id, /// This is used to create a unique interact ID for some widgets. /// This value is based on where in the hierarchy of widgets this Ui is in, /// and the value is increment with each added child widget. /// This works as an Id source only as long as new widgets aren't added or removed. /// They are therefore only good for Id:s that has no state. next_auto_id: u64, /// Specifies paint layer, clip rectangle and a reference to `Context`. painter: Painter, /// The `Style` (visuals, spacing, etc) of this ui. /// Commonly many `Ui`:s share the same `Style`. /// The `Ui` implements copy-on-write for this. style: std::sync::Arc<Style>, /// Handles the `Ui` size and the placement of new widgets. placer: Placer, /// If false we are unresponsive to input, /// and all widgets will assume a gray style. enabled: bool, } impl Ui { // ------------------------------------------------------------------------ // Creation: pub fn new(ctx: CtxRef, layer_id: LayerId, id: Id, max_rect: Rect, clip_rect: Rect) -> Self { let style = ctx.style(); Ui { id, next_auto_id: id.with("auto").value(), painter: Painter::new(ctx, layer_id, clip_rect), style, placer: Placer::new(max_rect, Layout::default()), enabled: true, } } pub fn child_ui(&mut self, max_rect: Rect, layout: Layout) -> Self { self.next_auto_id = self.next_auto_id.wrapping_add(1); Ui { id: self.id.with("child"), next_auto_id: Id::new(self.next_auto_id).with("child").value(), painter: self.painter.clone(), style: self.style.clone(), placer: Placer::new(max_rect, layout), enabled: self.enabled, } } /// Empty `Ui` for use in tests. pub fn __test() -> Self { let mut ctx = CtxRef::default(); ctx.begin_frame(Default::default()); let id = Id::new("__test"); let layer_id = LayerId::new(Order::Middle, id); let rect = Rect::from_min_size(Pos2::new(0.0, 0.0), vec2(1000.0, 1000.0)); Self::new(ctx, layer_id, id, rect, rect) } // ------------------------------------------------- /// A unique identity of this `Ui`. pub fn id(&self) -> Id { self.id } /// Style options for this `Ui` and its children. pub fn style(&self) -> &std::sync::Arc<Style> { &self.style } /// Mutably borrow internal `Style`. /// Changes apply to this `Ui` and its subsequent children. /// /// To set the style of all `Ui`:s, use [`Context::set_style`]. /// /// Example: /// ``` /// # let ui = &mut egui::Ui::__test(); /// ui.style_mut().body_text_style = egui::TextStyle::Heading; /// ``` pub fn style_mut(&mut self) -> &mut Style { std::sync::Arc::make_mut(&mut self.style) // clone-on-write } /// Changes apply to this `Ui` and its subsequent children. /// /// To set the visuals of all `Ui`:s, use [`Context::set_visuals`]. pub fn set_style(&mut self, style: impl Into<std::sync::Arc<Style>>) { self.style = style.into(); } /// The current spacing options for this `Ui`. /// Short for `ui.style().spacing`. pub fn spacing(&self) -> &crate::style::Spacing { &self.style.spacing } /// Mutably borrow internal `Spacing`. /// Changes apply to this `Ui` and its subsequent children. /// /// Example: /// ``` /// # let ui = &mut egui::Ui::__test(); /// ui.spacing_mut().item_spacing = egui::vec2(10.0, 2.0); /// ``` pub fn spacing_mut(&mut self) -> &mut crate::style::Spacing { &mut self.style_mut().spacing } /// The current visuals settings of this `Ui`. /// Short for `ui.style().visuals`. pub fn visuals(&self) -> &crate::Visuals { &self.style.visuals } /// Mutably borrow internal `visuals`. /// Changes apply to this `Ui` and its subsequent children. /// /// To set the visuals of all `Ui`:s, use [`Context::set_visuals`]. /// /// Example: /// ``` /// # let ui = &mut egui::Ui::__test(); /// ui.visuals_mut().override_text_color = Some(egui::Color32::RED); /// ``` pub fn visuals_mut(&mut self) -> &mut crate::Visuals { &mut self.style_mut().visuals } /// Get a reference to the parent [`CtxRef`]. pub fn ctx(&self) -> &CtxRef { self.painter.ctx() } /// Use this to paint stuff within this `Ui`. pub fn painter(&self) -> &Painter { &self.painter } /// If `false`, the `Ui` does not allow any interaction and /// the widgets in it will draw with a gray look. pub fn enabled(&self) -> bool { self.enabled } /// Calling `set_enabled(false)` will cause the `Ui` to deny all future interaction /// and all the widgets will draw with a gray look. /// /// Calling `set_enabled(true)` has no effect - it will NOT re-enable the `Ui` once disabled. /// /// ### Example /// ``` /// # let ui = &mut egui::Ui::__test(); /// # let mut enabled = true; /// ui.group(|ui|{ /// ui.checkbox(&mut enabled, "Enable subsection"); /// ui.set_enabled(enabled); /// if ui.button("Button that is not always clickable").clicked() { /// /* … */ /// } /// }); /// ``` pub fn set_enabled(&mut self, enabled: bool) { self.enabled &= enabled; if self.enabled { self.painter.set_fade_to_color(None); } else { self.painter .set_fade_to_color(Some(self.visuals().window_fill())); } } pub fn layout(&self) -> &Layout { self.placer.layout() } /// Should text wrap in this `Ui`? /// This is determined first by [`Style::wrap`], and then by the layout of this `Ui`. pub fn wrap_text(&self) -> bool { if let Some(wrap) = self.style.wrap { wrap } else if let Some(grid) = self.placer.grid() { grid.wrap_text() } else { // In vertical layouts we wrap text, but in horizontal we keep going. self.layout().is_vertical() } } /// Create a painter for a sub-region of this Ui. /// /// The clip-rect of the returned `Painter` will be the intersection /// of the given rectangle and the `clip_rect()` of this `Ui`. pub fn painter_at(&self, rect: Rect) -> Painter { self.painter().sub_region(rect) } /// Use this to paint stuff within this `Ui`. pub fn layer_id(&self) -> LayerId { self.painter().layer_id() } /// The `Input` of the `Context` associated with the `Ui`. /// Equivalent to `.ctx().input()`. pub fn input(&self) -> &InputState { self.ctx().input() } /// The `Memory` of the `Context` associated with the `Ui`. /// Equivalent to `.ctx().memory()`. pub fn memory(&self) -> MutexGuard<'_, Memory> { self.ctx().memory() } /// The `Output` of the `Context` associated with the `Ui`. /// Equivalent to `.ctx().output()`. pub fn output(&self) -> MutexGuard<'_, Output> { self.ctx().output() } /// The `Fonts` of the `Context` associated with the `Ui`. /// Equivalent to `.ctx().fonts()`. pub fn fonts(&self) -> &Fonts { self.ctx().fonts() } /// Screen-space rectangle for clipping what we paint in this ui. /// This is used, for instance, to avoid painting outside a window that is smaller than its contents. pub fn clip_rect(&self) -> Rect { self.painter.clip_rect() } /// Screen-space rectangle for clipping what we paint in this ui. /// This is used, for instance, to avoid painting outside a window that is smaller than its contents. pub fn set_clip_rect(&mut self, clip_rect: Rect) { self.painter.set_clip_rect(clip_rect); } } // ------------------------------------------------------------------------ /// # Sizes etc impl Ui { /// Where and how large the `Ui` is already. /// All widgets that have been added ot this `Ui` fits within this rectangle. /// /// No matter what, the final Ui will be at least this large. /// /// This will grow as new widgets are added, but never shrink. pub fn min_rect(&self) -> Rect { self.placer.min_rect() } /// Size of content; same as `min_rect().size()` pub fn min_size(&self) -> Vec2 { self.min_rect().size() } /// New widgets will *try* to fit within this rectangle. /// /// Text labels will wrap to fit within `max_rect`. /// Separator lines will span the `max_rect`. /// /// If a new widget doesn't fit within the `max_rect` then the /// `Ui` will make room for it by expanding both `min_rect` and `max_rect`. pub fn max_rect(&self) -> Rect { self.placer.max_rect() } /// This is like `max_rect()`, but will never be infinite. /// This can be useful for widgets that expand to fit the available space. pub fn max_rect_finite(&self) -> Rect { self.placer.max_rect_finite() } /// Used for animation, kind of hacky pub(crate) fn force_set_min_rect(&mut self, min_rect: Rect) { self.placer.force_set_min_rect(min_rect) } // ------------------------------------------------------------------------ /// Set the maximum size of the ui. /// You won't be able to shrink it below the current minimum size. pub fn set_max_size(&mut self, size: Vec2) { self.set_max_width(size.x); self.set_max_height(size.y); } /// Set the maximum width of the ui. /// You won't be able to shrink it below the current minimum size. pub fn set_max_width(&mut self, width: f32) { self.placer.set_max_width(width); } /// Set the maximum height of the ui. /// You won't be able to shrink it below the current minimum size. pub fn set_max_height(&mut self, height: f32) { self.placer.set_max_height(height); } // ------------------------------------------------------------------------ /// Set the minimum size of the ui. /// This can't shrink the ui, only make it larger. pub fn set_min_size(&mut self, size: Vec2) { self.set_min_width(size.x); self.set_min_height(size.y); } /// Set the minimum width of the ui. /// This can't shrink the ui, only make it larger. pub fn set_min_width(&mut self, width: f32) { self.placer.set_min_width(width); } /// Set the minimum height of the ui. /// This can't shrink the ui, only make it larger. pub fn set_min_height(&mut self, height: f32) { self.placer.set_min_height(height); } // ------------------------------------------------------------------------ /// Helper: shrinks the max width to the current width, /// so further widgets will try not to be wider than previous widgets. /// Useful for normal vertical layouts. pub fn shrink_width_to_current(&mut self) { self.set_max_width(self.min_rect().width()) } /// Helper: shrinks the max height to the current height, /// so further widgets will try not to be wider than previous widgets. pub fn shrink_height_to_current(&mut self) { self.set_max_height(self.min_rect().height()) } /// Expand the `min_rect` and `max_rect` of this ui to include a child at the given rect. pub fn expand_to_include_rect(&mut self, rect: Rect) { self.placer.expand_to_include_rect(rect); } /// `ui.set_width_range(min..=max);` is equivalent to `ui.set_min_width(min); ui.set_max_width(max);`. pub fn set_width_range(&mut self, width: std::ops::RangeInclusive<f32>) { self.set_min_width(*width.start()); self.set_max_width(*width.end()); } /// `ui.set_width_range(width);` is equivalent to `ui.set_min_width(width); ui.set_max_width(width);`. pub fn set_width(&mut self, width: f32) { self.set_min_width(width); self.set_max_width(width); } /// Ensure we are big enough to contain the given x-coordinate. /// This is sometimes useful to expand an ui to stretch to a certain place. pub fn expand_to_include_x(&mut self, x: f32) { self.placer.expand_to_include_x(x); } // ------------------------------------------------------------------------ // Layout related measures: /// The available space at the moment, given the current cursor. /// This how much more space we can take up without overflowing our parent. /// Shrinks as widgets allocate space and the cursor moves. /// A small size should be interpreted as "as little as possible". /// An infinite size should be interpreted as "as much as you want". pub fn available_size(&self) -> Vec2 { self.placer.available_size() } pub fn available_width(&self) -> f32 { self.available_size().x } /// In case of a wrapping layout, how much space is left on this row/column? pub fn available_size_before_wrap(&self) -> Vec2 { self.placer.available_rect_before_wrap().size() } /// This is like `available_size_before_wrap()`, but will never be infinite. /// This can be useful for widgets that expand to fit the available space. /// In most layouts the next widget will be put in the top left corner of this `Rect`. pub fn available_size_before_wrap_finite(&self) -> Vec2 { self.placer.available_rect_before_wrap_finite().size() } pub fn available_rect_before_wrap(&self) -> Rect { self.placer.available_rect_before_wrap() } /// This is like `available_rect_before_wrap()`, but will never be infinite. /// This can be useful for widgets that expand to fit the available space. /// In most layouts the next widget will be put in the top left corner of this `Rect`. pub fn available_rect_before_wrap_finite(&self) -> Rect { self.placer.available_rect_before_wrap_finite() } } /// # `Id` creation impl Ui { /// Use this to generate widget ids for widgets that have persistent state in `Memory`. pub fn make_persistent_id<IdSource>(&self, id_source: IdSource) -> Id where IdSource: Hash + std::fmt::Debug, { self.id.with(&id_source) } #[deprecated = "This id now returned from ui.allocate_space"] pub fn make_position_id(&self) -> Id { Id::new(self.next_auto_id) } pub(crate) fn auto_id_with<IdSource>(&self, id_source: IdSource) -> Id where IdSource: Hash + std::fmt::Debug, { Id::new(self.next_auto_id).with(id_source) } } /// # Interaction impl Ui { pub fn interact(&self, rect: Rect, id: Id, sense: Sense) -> Response { self.ctx().interact( self.clip_rect(), self.spacing().item_spacing, self.layer_id(), id, rect, sense, self.enabled, ) } /// Is the pointer (mouse/touch) above this rectangle in this `Ui`? /// /// The `clip_rect` and layer of this `Ui` will be respected, so, for instance, /// if this `Ui` is behind some other window, this will always return `false`. pub fn rect_contains_pointer(&self, rect: Rect) -> bool { self.ctx() .rect_contains_pointer(self.layer_id(), self.clip_rect().intersect(rect)) } /// Is the pointer (mouse/touch) above this `Ui`? /// Equivalent to `ui.rect_contains_pointer(ui.min_rect())` pub fn ui_contains_pointer(&self) -> bool { self.rect_contains_pointer(self.min_rect()) } #[deprecated = "renamed rect_contains_pointer"] pub fn rect_contains_mouse(&self, rect: Rect) -> bool { self.rect_contains_pointer(rect) } #[deprecated = "renamed ui_contains_pointer"] pub fn ui_contains_mouse(&self) -> bool { self.ui_contains_pointer() } #[deprecated = "Use: interact(rect, id, Sense::hover())"] pub fn interact_hover(&self, rect: Rect) -> Response { self.interact(rect, self.auto_id_with("hover_rect"), Sense::hover()) } #[deprecated = "Use: rect_contains_pointer()"] pub fn hovered(&self, rect: Rect) -> bool { self.interact(rect, self.id, Sense::hover()).hovered } // ------------------------------------------------------------------------ // Stuff that moves the cursor, i.e. allocates space in this ui! /// Advance the cursor (where the next widget is put) by this many points. /// /// The direction is dependent on the layout. /// This is useful for creating some extra space between widgets. /// /// [`Self::min_rect`] will expand to contain the cursor. pub fn advance_cursor(&mut self, amount: f32) { self.placer.advance_cursor(amount); } } /// # Allocating space: where do I put my widgets? impl Ui { /// Allocate space for a widget and check for interaction in the space. /// Returns a `Response` which contains a rectangle, id, and interaction info. /// /// ## How sizes are negotiated /// Each widget should have a *minimum desired size* and a *desired size*. /// When asking for space, ask AT LEAST for you minimum, and don't ask for more than you need. /// If you want to fill the space, ask about `available().size()` and use that. /// /// You may get MORE space than you asked for, for instance /// for justified layouts, like in menus. /// /// You will never get a rectangle that is smaller than the amount of space you asked for. /// /// ``` /// # let mut ui = egui::Ui::__test(); /// let response = ui.allocate_response(egui::vec2(100.0, 200.0), egui::Sense::click()); /// if response.clicked() { /* … */ } /// ui.painter().rect_stroke(response.rect, 0.0, (1.0, egui::Color32::WHITE)); /// ``` pub fn allocate_response(&mut self, desired_size: Vec2, sense: Sense) -> Response { let (id, rect) = self.allocate_space(desired_size); self.interact(rect, id, sense) } /// Returns a `Rect` with exactly what you asked for. /// /// The response rect will be larger if this is part of a justified layout or similar. /// This means that iof this is a narrow widget in a wide justified layout, then /// the widget will react to interactions outside the returned `Rect`. pub fn allocate_exact_size(&mut self, desired_size: Vec2, sense: Sense) -> (Rect, Response) { let response = self.allocate_response(desired_size, sense); let rect = self .placer .align_size_within_rect(desired_size, response.rect); (rect, response) } /// Allocate at least as much space as needed, and interact with that rect. /// /// The returned `Rect` will be the same size as `Response::rect`. pub fn allocate_at_least(&mut self, desired_size: Vec2, sense: Sense) -> (Rect, Response) { let response = self.allocate_response(desired_size, sense); (response.rect, response) } /// Reserve this much space and move the cursor. /// Returns where to put the widget. /// /// ## How sizes are negotiated /// Each widget should have a *minimum desired size* and a *desired size*. /// When asking for space, ask AT LEAST for you minimum, and don't ask for more than you need. /// If you want to fill the space, ask about `available().size()` and use that. /// /// You may get MORE space than you asked for, for instance /// for justified layouts, like in menus. /// /// You will never get a rectangle that is smaller than the amount of space you asked for. /// /// Returns an automatic `Id` (which you can use for interaction) and the `Rect` of where to put your widget. /// /// ``` /// # let mut ui = egui::Ui::__test(); /// let (id, rect) = ui.allocate_space(egui::vec2(100.0, 200.0)); /// let response = ui.interact(rect, id, egui::Sense::click()); /// ``` pub fn allocate_space(&mut self, desired_size: Vec2) -> (Id, Rect) { // For debug rendering let original_available = self.available_size_before_wrap(); let too_wide = desired_size.x > original_available.x; let too_high = desired_size.y > original_available.y; let rect = self.allocate_space_impl(desired_size); let debug_expand_width = self.visuals().debug_expand_width; let debug_expand_height = self.visuals().debug_expand_height; if (debug_expand_width && too_wide) || (debug_expand_height && too_high) { self.painter .rect_stroke(rect, 0.0, (1.0, Color32::LIGHT_BLUE)); let stroke = Stroke::new(2.5, Color32::from_rgb(200, 0, 0)); let paint_line_seg = |a, b| self.painter().line_segment([a, b], stroke); if debug_expand_width && too_wide { paint_line_seg(rect.left_top(), rect.left_bottom()); paint_line_seg(rect.left_center(), rect.right_center()); paint_line_seg( pos2(rect.left() + original_available.x, rect.top()), pos2(rect.left() + original_available.x, rect.bottom()), ); paint_line_seg(rect.right_top(), rect.right_bottom()); } if debug_expand_height && too_high { paint_line_seg(rect.left_top(), rect.right_top()); paint_line_seg(rect.center_top(), rect.center_bottom()); paint_line_seg(rect.left_bottom(), rect.right_bottom()); } } self.next_auto_id = self.next_auto_id.wrapping_add(1); let id = Id::new(self.next_auto_id); (id, rect) } /// Reserve this much space and move the cursor. /// Returns where to put the widget. fn allocate_space_impl(&mut self, desired_size: Vec2) -> Rect { let item_spacing = self.spacing().item_spacing; let frame_rect = self.placer.next_space(desired_size, item_spacing); let widget_rect = self.placer.justify_and_align(frame_rect, desired_size); self.placer .advance_after_rects(frame_rect, widget_rect, item_spacing); widget_rect } /// Allocate a specific part of the `Ui‘. /// Ignore the layout of the `Ui‘: just put my widget here! pub(crate) fn allocate_rect(&mut self, rect: Rect, sense: Sense) -> Response { let id = self.advance_cursor_after_rect(rect); self.interact(rect, id, sense) } pub(crate) fn advance_cursor_after_rect(&mut self, rect: Rect) -> Id { let item_spacing = self.spacing().item_spacing; self.placer.advance_after_rects(rect, rect, item_spacing); self.next_auto_id = self.next_auto_id.wrapping_add(1); Id::new(self.next_auto_id) } pub(crate) fn cursor(&self) -> Pos2 { self.placer.cursor() } /// Allocated the given space and then adds content to that space. /// If the contents overflow, more space will be allocated. /// When finished, the amount of space actually used (`min_rect`) will be allocated. /// So you can request a lot of space and then use less. pub fn allocate_ui<R>( &mut self, desired_size: Vec2, add_contents: impl FnOnce(&mut Self) -> R, ) -> InnerResponse<R> { let item_spacing = self.spacing().item_spacing; let outer_child_rect = self.placer.next_space(desired_size, item_spacing); let inner_child_rect = self .placer .justify_and_align(outer_child_rect, desired_size); let mut child_ui = self.child_ui(inner_child_rect, *self.layout()); let ret = add_contents(&mut child_ui); let final_child_rect = child_ui.min_rect(); self.placer.advance_after_rects( outer_child_rect.union(final_child_rect), final_child_rect, item_spacing, ); let response = self.interact(final_child_rect, child_ui.id, Sense::hover()); InnerResponse::new(ret, response) } /// Allocated the given rectangle and then adds content to that rectangle. /// If the contents overflow, more space will be allocated. /// When finished, the amount of space actually used (`min_rect`) will be allocated. /// So you can request a lot of space and then use less. pub fn allocate_ui_at_rect<R>( &mut self, max_rect: Rect, add_contents: impl FnOnce(&mut Self) -> R, ) -> InnerResponse<R> { let mut child_ui = self.child_ui(max_rect, *self.layout()); let ret = add_contents(&mut child_ui); let final_child_rect = child_ui.min_rect(); self.placer.advance_after_rects( final_child_rect, final_child_rect, self.spacing().item_spacing, ); let response = self.interact(final_child_rect, child_ui.id, Sense::hover()); InnerResponse::new(ret, response) } /// Convenience function to get a region to paint on pub fn allocate_painter(&mut self, desired_size: Vec2, sense: Sense) -> (Response, Painter) { let response = self.allocate_response(desired_size, sense); let clip_rect = self.clip_rect().intersect(response.rect); // Make sure we don't paint out of bounds let painter = Painter::new(self.ctx().clone(), self.layer_id(), clip_rect); (response, painter) } /// Move the scroll to this cursor position with the specified alignment. /// /// ``` /// # use egui::Align; /// # let mut ui = &mut egui::Ui::__test(); /// egui::ScrollArea::auto_sized().show(ui, |ui| { /// let scroll_bottom = ui.button("Scroll to bottom.").clicked(); /// for i in 0..1000 { /// ui.label(format!("Item {}", i)); /// } /// /// if scroll_bottom { /// ui.scroll_to_cursor(Align::BOTTOM); /// } /// }); /// ``` pub fn scroll_to_cursor(&mut self, align: Align) { let scroll_y = self.cursor().y; self.ctx().frame_state().scroll_target = Some((scroll_y, align)); } } /// # Adding widgets impl Ui { /// Add a [`Widget`] to this `Ui` at a location dependent on the current [`Layout`]. /// /// The returned [`Response`] can be used to check for interactions, /// as well as adding tooltips using [`Response::on_hover_text`]. /// /// ``` /// # let mut ui = egui::Ui::__test(); /// # let mut my_value = 42; /// let response = ui.add(egui::Slider::i32(&mut my_value, 0..=100)); /// response.on_hover_text("Drag me!"); /// ``` pub fn add(&mut self, widget: impl Widget) -> Response { widget.ui(self) } /// Add a [`Widget`] to this `Ui` with a given max size. pub fn add_sized(&mut self, max_size: Vec2, widget: impl Widget) -> Response { self.allocate_ui(max_size, |ui| { ui.centered_and_justified(|ui| ui.add(widget)).inner }) .inner } /// Add a [`Widget`] to this `Ui` at a specific location (manual layout). pub fn put(&mut self, max_rect: Rect, widget: impl Widget) -> Response { self.allocate_ui_at_rect(max_rect, |ui| { ui.centered_and_justified(|ui| ui.add(widget)).inner }) .inner } /// Shortcut for `add(Label::new(text))` /// /// Se also [`Label`]. pub fn label(&mut self, label: impl Into<Label>) -> Response { self.add(label.into()) } /// Shortcut for `add(Label::new(text).text_color(color))` pub fn colored_label( &mut self, color: impl Into<Color32>, label: impl Into<Label>, ) -> Response { self.add(label.into().text_color(color)) } /// Shortcut for `add(Label::new(text).heading())` pub fn heading(&mut self, label: impl Into<Label>) -> Response { self.add(label.into().heading()) } /// Shortcut for `add(Label::new(text).monospace())` pub fn monospace(&mut self, label: impl Into<Label>) -> Response { self.add(label.into().monospace()) } /// Show text as monospace with a gray background. /// /// Shortcut for `add(Label::new(text).code())` pub fn code(&mut self, label: impl Into<Label>) -> Response { self.add(label.into().code()) } /// Shortcut for `add(Label::new(text).small())` pub fn small(&mut self, label: impl Into<Label>) -> Response { self.add(label.into().small()) } /// Shortcut for `add(Hyperlink::new(url))` /// /// Se also [`Hyperlink`]. pub fn hyperlink(&mut self, url: impl Into<String>) -> Response { self.add(Hyperlink::new(url)) } /// Shortcut for `add(Hyperlink::new(url).text(label))` /// /// ``` /// # let ui = &mut egui::Ui::__test(); /// ui.hyperlink_to("egui on GitHub", "https://www.github.com/emilk/egui/"); /// ``` /// /// Se also [`Hyperlink`]. pub fn hyperlink_to(&mut self, label: impl Into<String>, url: impl Into<String>) -> Response { self.add(Hyperlink::new(url).text(label)) } #[deprecated = "Use `text_edit_singleline` or `text_edit_multiline`"] pub fn text_edit(&mut self, text: &mut String) -> Response { self.text_edit_multiline(text) } /// Now newlines (`\n`) allowed. Pressing enter key will result in the `TextEdit` loosing focus (`response.lost_kb_focus`). /// /// Se also [`TextEdit`]. pub fn text_edit_singleline(&mut self, text: &mut String) -> Response { self.add(TextEdit::singleline(text)) } /// A `TextEdit` for multiple lines. Pressing enter key will create a new line. /// /// Se also [`TextEdit`]. pub fn text_edit_multiline(&mut self, text: &mut String) -> Response { self.add(TextEdit::multiline(text)) } /// Usage: `if ui.button("Click me").clicked() { … }` /// /// Shortcut for `add(Button::new(text))` /// /// Se also [`Button`]. #[must_use = "You should check if the user clicked this with `if ui.button(…).clicked() { … } "] pub fn button(&mut self, text: impl Into<String>) -> Response { self.add(Button::new(text)) } /// A button as small as normal body text. /// /// Usage: `if ui.small_button("Click me").clicked() { … }` /// /// Shortcut for `add(Button::new(text).small())` #[must_use = "You should check if the user clicked this with `if ui.small_button(…).clicked() { … } "] pub fn small_button(&mut self, text: impl Into<String>) -> Response { self.add(Button::new(text).small()) } /// Show a checkbox. pub fn checkbox(&mut self, checked: &mut bool, text: impl Into<String>) -> Response { self.add(Checkbox::new(checked, text)) } /// Show a [`RadioButton`]. /// Often you want to use [`Self::radio_value`] instead. #[must_use = "You should check if the user clicked this with `if ui.radio(…).clicked() { … } "] pub fn radio(&mut self, selected: bool, text: impl Into<String>) -> Response { self.add(RadioButton::new(selected, text)) } /// Show a [`RadioButton`]. It is selected if `*current_value == selected_value`. /// If clicked, `selected_value` is assigned to `*current_value`. /// /// ``` /// # let ui = &mut egui::Ui::__test(); /// /// #[derive(PartialEq)] /// enum Enum { First, Second, Third } /// let mut my_enum = Enum::First; /// /// ui.radio_value(&mut my_enum, Enum::First, "First"); /// /// // is equivalent to: /// /// if ui.add(egui::RadioButton::new(my_enum == Enum::First, "First")).clicked() { /// my_enum = Enum::First /// } pub fn radio_value<Value: PartialEq>( &mut self, current_value: &mut Value, selected_value: Value, text: impl Into<String>, ) -> Response { let mut response = self.radio(*current_value == selected_value, text); if response.clicked() { *current_value = selected_value; response.mark_changed(); } response } /// Show a label which can be selected or not. /// /// Se also [`SelectableLabel`]. #[must_use = "You should check if the user clicked this with `if ui.selectable_label(…).clicked() { … } "] pub fn selectable_label(&mut self, checked: bool, text: impl Into<String>) -> Response { self.add(SelectableLabel::new(checked, text)) } /// Show selectable text. It is selected if `*current_value == selected_value`. /// If clicked, `selected_value` is assigned to `*current_value`. /// /// Example: `ui.selectable_value(&mut my_enum, Enum::Alternative, "Alternative")`. /// /// Se also [`SelectableLabel`]. pub fn selectable_value<Value: PartialEq>( &mut self, current_value: &mut Value, selected_value: Value, text: impl Into<String>, ) -> Response { let mut response = self.selectable_label(*current_value == selected_value, text); if response.clicked() { *current_value = selected_value; response.mark_changed(); } response } /// Shortcut for `add(Separator::new())` (see [`Separator`]). pub fn separator(&mut self) -> Response { self.add(Separator::new()) } /// Modify an angle. The given angle should be in radians, but is shown to the user in degrees. /// The angle is NOT wrapped, so the user may select, for instance 720° = 2𝞃 = 4π pub fn drag_angle(&mut self, radians: &mut f32) -> Response { #![allow(clippy::float_cmp)] let mut degrees = radians.to_degrees(); let mut response = self.add(DragValue::f32(&mut degrees).speed(1.0).suffix("°")); // only touch `*radians` if we actually changed the degree value if degrees != radians.to_degrees() { *radians = degrees.to_radians(); response.changed = true; } response } /// Modify an angle. The given angle should be in radians, /// but is shown to the user in fractions of one Tau (i.e. fractions of one turn). /// The angle is NOT wrapped, so the user may select, for instance 2𝞃 (720°) pub fn drag_angle_tau(&mut self, radians: &mut f32) -> Response { #![allow(clippy::float_cmp)] use std::f32::consts::TAU; let mut taus = *radians / TAU; let mut response = self .add(DragValue::f32(&mut taus).speed(0.01).suffix("τ")) .on_hover_text("1τ = one turn, 0.5τ = half a turn, etc. 0.25τ = 90°"); // only touch `*radians` if we actually changed the value if taus != *radians / TAU { *radians = taus * TAU; response.changed = true; } response } /// Show an image here with the given size. /// /// See also [`Image`]. pub fn image(&mut self, texture_id: TextureId, size: impl Into<Vec2>) -> Response { self.add(Image::new(texture_id, size)) } } /// # Colors impl Ui { /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. pub fn color_edit_button_srgba(&mut self, srgba: &mut Color32) -> Response { color_picker::color_edit_button_srgba(self, srgba, color_picker::Alpha::BlendOrAdditive) } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. pub fn color_edit_button_hsva(&mut self, hsva: &mut Hsva) -> Response { color_picker::color_edit_button_hsva(self, hsva, color_picker::Alpha::BlendOrAdditive) } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. /// The given color is in `sRGB` space. pub fn color_edit_button_srgb(&mut self, srgb: &mut [u8; 3]) -> Response { let mut hsva = Hsva::from_srgb(*srgb); let response = color_picker::color_edit_button_hsva(self, &mut hsva, color_picker::Alpha::Opaque); *srgb = hsva.to_srgb(); response } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. /// The given color is in linear RGB space. pub fn color_edit_button_rgb(&mut self, rgb: &mut [f32; 3]) -> Response { let mut hsva = Hsva::from_rgb(*rgb); let response = color_picker::color_edit_button_hsva(self, &mut hsva, color_picker::Alpha::Opaque); *rgb = hsva.to_rgb(); response } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. /// The given color is in `sRGBA` space with premultiplied alpha pub fn color_edit_button_srgba_premultiplied(&mut self, srgba: &mut [u8; 4]) -> Response { let mut color = Color32::from_rgba_premultiplied(srgba[0], srgba[1], srgba[2], srgba[3]); let response = self.color_edit_button_srgba(&mut color); *srgba = color.to_array(); response } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. /// The given color is in `sRGBA` space without premultiplied alpha. /// If unsure, what "premultiplied alpha" is, then this is probably the function you want to use. pub fn color_edit_button_srgba_unmultiplied(&mut self, srgba: &mut [u8; 4]) -> Response { let mut hsva = Hsva::from_srgba_unmultiplied(*srgba); let response = color_picker::color_edit_button_hsva(self, &mut hsva, color_picker::Alpha::OnlyBlend); *srgba = hsva.to_srgba_unmultiplied(); response } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. /// The given color is in linear RGBA space with premultiplied alpha pub fn color_edit_button_rgba_premultiplied(&mut self, rgba: &mut [f32; 4]) -> Response { let mut hsva = Hsva::from_rgba_premultiplied(*rgba); let response = color_picker::color_edit_button_hsva( self, &mut hsva, color_picker::Alpha::BlendOrAdditive, ); *rgba = hsva.to_rgba_premultiplied(); response } /// Shows a button with the given color. /// If the user clicks the button, a full color picker is shown. /// The given color is in linear RGBA space without premultiplied alpha. /// If unsure, what "premultiplied alpha" is, then this is probably the function you want to use. pub fn color_edit_button_rgba_unmultiplied(&mut self, rgba: &mut [f32; 4]) -> Response { let mut hsva = Hsva::from_rgba_unmultiplied(*rgba); let response = color_picker::color_edit_button_hsva(self, &mut hsva, color_picker::Alpha::OnlyBlend); *rgba = hsva.to_rgba_unmultiplied(); response } } /// # Adding Containers / Sub-uis: impl Ui { /// Put into a `Frame::group`, visually grouping the contents together pub fn group<R>(&mut self, add_contents: impl FnOnce(&mut Ui) -> R) -> R { crate::Frame::group(self.style()).show(self, add_contents) } /// Create a child ui. You can use this to temporarily change the Style of a sub-region, for instance. pub fn wrap<R>(&mut self, add_contents: impl FnOnce(&mut Ui) -> R) -> InnerResponse<R> { let child_rect = self.available_rect_before_wrap(); let mut child_ui = self.child_ui(child_rect, *self.layout()); let ret = add_contents(&mut child_ui); let size = child_ui.min_size(); let response = self.allocate_response(size, Sense::hover()); InnerResponse::new(ret, response) } /// Redirect shapes to another paint layer. pub fn with_layer_id<R>( &mut self, layer_id: LayerId, add_contents: impl FnOnce(&mut Self) -> R, ) -> InnerResponse<R> { self.wrap(|ui| { ui.painter.set_layer_id(layer_id); add_contents(ui) }) } #[deprecated = "Use `ui.allocate_ui` instead"] pub fn add_custom_contents( &mut self, desired_size: Vec2, add_contents: impl FnOnce(&mut Ui), ) -> Rect { self.allocate_ui(desired_size, add_contents).response.rect } /// A [`CollapsingHeader`] that starts out collapsed. pub fn collapsing<R>( &mut self, heading: impl Into<String>, add_contents: impl FnOnce(&mut Ui) -> R, ) -> CollapsingResponse<R> { CollapsingHeader::new(heading).show(self, add_contents) } /// Create a child ui which is indented to the right. pub fn indent<R>( &mut self, id_source: impl Hash, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { assert!( self.layout().is_vertical(), "You can only indent vertical layouts, found {:?}", self.layout() ); let indent = vec2(self.spacing().indent, 0.0); let child_rect = Rect::from_min_max(self.cursor() + indent, self.max_rect().right_bottom()); // TODO: wrong for reversed layouts let mut child_ui = Self { id: self.id.with(id_source), ..self.child_ui(child_rect, *self.layout()) }; let ret = add_contents(&mut child_ui); let end_with_horizontal_line = true; if end_with_horizontal_line { child_ui.advance_cursor(4.0); } let size = child_ui.min_size(); // draw a faint line on the left to mark the indented section let stroke = self.visuals().widgets.noninteractive.bg_stroke; let left_top = child_rect.min - indent * 0.5; let left_top = self.painter().round_pos_to_pixels(left_top); let left_bottom = pos2(left_top.x, left_top.y + size.y - 2.0); let left_bottom = self.painter().round_pos_to_pixels(left_bottom); self.painter.line_segment([left_top, left_bottom], stroke); if end_with_horizontal_line { let fudge = 2.0; // looks nicer with button rounding in collapsing headers let right_bottom = pos2(child_ui.min_rect().right() - fudge, left_bottom.y); self.painter .line_segment([left_bottom, right_bottom], stroke); } let response = self.allocate_response(indent + size, Sense::hover()); InnerResponse::new(ret, response) } #[deprecated] pub fn left_column(&mut self, width: f32) -> Self { #[allow(deprecated)] self.column(Align::Min, width) } #[deprecated] pub fn centered_column(&mut self, width: f32) -> Self { #[allow(deprecated)] self.column(Align::Center, width) } #[deprecated] pub fn right_column(&mut self, width: f32) -> Self { #[allow(deprecated)] self.column(Align::Max, width) } /// A column ui with a given width. #[deprecated] pub fn column(&mut self, column_position: Align, width: f32) -> Self { let x = match column_position { Align::Min => 0.0, Align::Center => self.available_width() / 2.0 - width / 2.0, Align::Max => self.available_width() - width, }; self.child_ui( Rect::from_min_size( self.cursor() + vec2(x, 0.0), vec2(width, self.available_size_before_wrap().y), ), *self.layout(), ) } /// Start a ui with horizontal layout. /// After you have called this, the function registers the contents as any other widget. /// /// Elements will be centered on the Y axis, i.e. /// adjusted up and down to lie in the center of the horizontal layout. /// The initial height is `style.spacing.interact_size.y`. /// Centering is almost always what you want if you are /// planning to to mix widgets or use different types of text. /// /// The returned `Response` will only have checked for mouse hover /// but can be used for tooltips (`on_hover_text`). /// It also contains the `Rect` used by the horizontal layout. pub fn horizontal<R>(&mut self, add_contents: impl FnOnce(&mut Ui) -> R) -> InnerResponse<R> { self.horizontal_with_main_wrap(false, add_contents) } /// Like `horizontal`, but will set up the spacing to match that of a normal label. /// /// In particular, the space between widgets is the same width as the space character. /// /// You can still add any widgets to the layout (not only Labels). pub fn horizontal_for_text<R>( &mut self, text_style: TextStyle, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { self.wrap(|ui| { let font = &ui.fonts()[text_style]; let row_height = font.row_height(); let space_width = font.glyph_width(' '); let spacing = ui.spacing_mut(); spacing.interact_size.y = row_height; spacing.item_spacing.x = space_width; spacing.item_spacing.y = 0.0; ui.horizontal(add_contents).inner }) } /// Start a ui with horizontal layout that wraps to a new row /// when it reaches the right edge of the `max_size`. /// After you have called this, the function registers the contents as any other widget. /// /// Elements will be centered on the Y axis, i.e. /// adjusted up and down to lie in the center of the horizontal layout. /// The initial height is `style.spacing.interact_size.y`. /// Centering is almost always what you want if you are /// planning to to mix widgets or use different types of text. /// /// The returned `Response` will only have checked for mouse hover /// but can be used for tooltips (`on_hover_text`). /// It also contains the `Rect` used by the horizontal layout. pub fn horizontal_wrapped<R>( &mut self, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { self.horizontal_with_main_wrap(true, add_contents) } /// Like `horizontal_wrapped`, but will set up the spacing and /// line size to match that of a normal label. /// /// In particular, the space between widgets is the same width as the space character /// and the line spacing is the same as that for text. /// /// You can still add any widgets to the layout (not only Labels). pub fn horizontal_wrapped_for_text<R>( &mut self, text_style: TextStyle, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { self.wrap(|ui| { let font = &ui.fonts()[text_style]; let row_height = font.row_height(); let space_width = font.glyph_width(' '); let spacing = ui.spacing_mut(); spacing.interact_size.y = row_height; spacing.item_spacing.x = space_width; spacing.item_spacing.y = 0.0; ui.horizontal_wrapped(add_contents).inner }) } fn horizontal_with_main_wrap<R>( &mut self, main_wrap: bool, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { let initial_size = vec2( self.available_size_before_wrap_finite().x, self.spacing().interact_size.y, // Assume there will be something interactive on the horizontal layout ); let layout = if self.placer.prefer_right_to_left() { Layout::right_to_left() } else { Layout::left_to_right() } .with_main_wrap(main_wrap); self.allocate_ui(initial_size, |ui| { ui.with_layout(layout, add_contents).inner }) } /// Start a ui with vertical layout. /// Widgets will be left-justified. pub fn vertical<R>(&mut self, add_contents: impl FnOnce(&mut Ui) -> R) -> InnerResponse<R> { self.with_layout(Layout::top_down(Align::Min), add_contents) } /// Start a ui with vertical layout. /// Widgets will be horizontally centered. pub fn vertical_centered<R>( &mut self, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { self.with_layout(Layout::top_down(Align::Center), add_contents) } /// Start a ui with vertical layout. /// Widgets will be horizontally centered and justified (fill full width). pub fn vertical_centered_justified<R>( &mut self, add_contents: impl FnOnce(&mut Ui) -> R, ) -> InnerResponse<R> { self.with_layout( Layout::top_down(Align::Center).with_cross_justify(true), add_contents, ) } pub fn with_layout<R>( &mut self, layout: Layout, add_contents: impl FnOnce(&mut Self) -> R, ) -> InnerResponse<R> { let mut child_ui = self.child_ui(self.available_rect_before_wrap(), layout); let inner = add_contents(&mut child_ui); let rect = child_ui.min_rect(); let item_spacing = self.spacing().item_spacing; self.placer.advance_after_rects(rect, rect, item_spacing); InnerResponse::new(inner, self.interact(rect, child_ui.id, Sense::hover())) } /// This will make the next added widget centered and justified in the available space. pub fn centered_and_justified<R>( &mut self, add_contents: impl FnOnce(&mut Self) -> R, ) -> InnerResponse<R> { self.with_layout( Layout::centered_and_justified(Direction::TopDown), add_contents, ) } pub(crate) fn set_grid(&mut self, grid: grid::GridLayout) { self.placer.set_grid(grid); } pub(crate) fn save_grid(&mut self) { self.placer.save_grid(); } pub(crate) fn is_grid(&self) -> bool { self.placer.is_grid() } pub(crate) fn grid(&self) -> Option<&grid::GridLayout> { self.placer.grid() } /// Move to the next row in a grid layout or wrapping layout. /// Otherwise does nothing. pub fn end_row(&mut self) { self.placer .end_row(self.spacing().item_spacing, &self.painter().clone()); } /// Temporarily split split an Ui into several columns. /// /// ``` /// # let mut ui = egui::Ui::__test(); /// ui.columns(2, |columns| { /// columns[0].label("First column"); /// columns[1].label("Second column"); /// }); /// ``` pub fn columns<F, R>(&mut self, num_columns: usize, add_contents: F) -> R where F: FnOnce(&mut [Self]) -> R, { // TODO: ensure there is space let spacing = self.spacing().item_spacing.x; let total_spacing = spacing * (num_columns as f32 - 1.0); let column_width = (self.available_width() - total_spacing) / (num_columns as f32); let top_left = self.cursor(); let mut columns: Vec<Self> = (0..num_columns) .map(|col_idx| { let pos = top_left + vec2((col_idx as f32) * (column_width + spacing), 0.0); let child_rect = Rect::from_min_max( pos, pos2(pos.x + column_width, self.max_rect().right_bottom().y), ); let mut column_ui = self.child_ui(child_rect, Layout::top_down_justified(Align::LEFT)); column_ui.set_width(column_width); column_ui }) .collect(); let result = add_contents(&mut columns[..]); let mut max_column_width = column_width; let mut max_height = 0.0; for column in &columns { max_column_width = max_column_width.max(column.min_rect().width()); max_height = column.min_size().y.max(max_height); } // Make sure we fit everything next frame: let total_required_width = total_spacing + max_column_width * (num_columns as f32); let size = vec2(self.available_width().max(total_required_width), max_height); self.advance_cursor_after_rect(Rect::from_min_size(top_left, size)); result } } // ---------------------------------------------------------------------------- /// # Debug stuff impl Ui { /// Shows where the next widget is going to be placed pub fn debug_paint_cursor(&self) { self.placer.debug_paint_cursor(&self.painter); } }