input_region/
input_region.rs

1// Copyright 2023 The Druid Authors.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15//! A demo of a few window features, including input region, always on top,
16//! and titlebar visibility.
17//! The demo is setup so that there are parts of the window that you can click through.
18//! There are also buttons for setting always on top and setting the visibility of the
19//! titlebar.
20//! The window's region is managed by the root custom widget.
21
22use druid::widget::prelude::*;
23use druid::widget::{Button, Container, Flex, Label, LineBreaking, Widget};
24use druid::{AppLauncher, Color, Lens, Point, Rect, Region, WidgetExt, WidgetPod, WindowDesc};
25
26const EXAMPLE_BORDER_SIZE: f64 = 3.0;
27const INFO_TEXT: &str = "Only this text and the borders can be interacted with.
28You can click through the other parts
29
30This demo is useful for observing the limitations of each OS.
31- Windows is well supported. Observation: When the titlebar is enabled and the input region is set, the border becomes invisible. Always on top is supported.
32- macOS has good support, but doesn't allow toggling titlebar after the window is opened. Also, it just makes transparent regions transparent automatically when set to have no titlebar. Always on top is supported.
33- Linux support varies by desktop environment and display server. Wayland is much more restrictive, with it not allowing things like setting position and always on top. Fortunately desktop environments often allow you to manually set window decoration and always on top on the Window itself. The offsets can differ between desktop environments, and sometimes you need to open the window with the titlebar, then turn it off, for it to work.";
34
35#[derive(Clone, Data, Lens)]
36struct AppState {
37    limit_input_region: bool,
38    show_titlebar: bool,
39    always_on_top: bool,
40}
41
42struct InputRegionExampleWidget {
43    info_label: WidgetPod<AppState, Container<AppState>>,
44    controls: WidgetPod<AppState, Flex<AppState>>,
45}
46
47impl InputRegionExampleWidget {
48    pub fn new() -> Self {
49        let info_label = Label::new(INFO_TEXT)
50            .with_line_break_mode(LineBreaking::WordWrap)
51            .padding(20.0)
52            .background(Color::rgba(0.2, 0.2, 0.2, 1.0));
53        let toggle_input_region = Button::new("Toggle Input Region")
54            .on_click(|ctx, data: &mut bool, _: &Env| {
55                *data = !*data;
56                tracing::debug!("Setting input region toggle to: {}", *data);
57                ctx.request_layout();
58            })
59            .lens(AppState::limit_input_region);
60        let toggle_titlebar = Button::new("Toggle TitleBar")
61            .on_click(|ctx, data: &mut bool, _: &Env| {
62                *data = !*data;
63                tracing::debug!("Setting titlebar visibility to: {}", *data);
64                ctx.window().show_titlebar(*data);
65                ctx.request_layout();
66            })
67            .lens(AppState::show_titlebar);
68        let toggle_always_on_top = Button::new("Toggle Always On Top")
69            .on_click(|ctx, data: &mut bool, _: &Env| {
70                *data = !*data;
71                tracing::debug!("Setting always on top to: {}", *data);
72                ctx.window().set_always_on_top(*data);
73            })
74            .lens(AppState::always_on_top);
75        let controls_flex = Flex::row()
76            .with_child(toggle_input_region)
77            .with_child(toggle_titlebar)
78            .with_child(toggle_always_on_top);
79        Self {
80            info_label: WidgetPod::new(info_label),
81            controls: WidgetPod::new(controls_flex),
82        }
83    }
84}
85
86impl Widget<AppState> for InputRegionExampleWidget {
87    fn event(
88        &mut self,
89        ctx: &mut druid::EventCtx,
90        event: &druid::Event,
91        data: &mut AppState,
92        env: &druid::Env,
93    ) {
94        self.info_label.event(ctx, event, data, env);
95        self.controls.event(ctx, event, data, env);
96    }
97
98    fn lifecycle(
99        &mut self,
100        ctx: &mut druid::LifeCycleCtx,
101        event: &druid::LifeCycle,
102        data: &AppState,
103        env: &druid::Env,
104    ) {
105        self.info_label.lifecycle(ctx, event, data, env);
106        self.controls.lifecycle(ctx, event, data, env);
107    }
108
109    fn update(
110        &mut self,
111        ctx: &mut druid::UpdateCtx,
112        _old_data: &AppState,
113        data: &AppState,
114        env: &druid::Env,
115    ) {
116        self.info_label.update(ctx, data, env);
117        self.controls.update(ctx, data, env);
118    }
119
120    fn layout(
121        &mut self,
122        ctx: &mut druid::LayoutCtx,
123        bc: &druid::BoxConstraints,
124        data: &AppState,
125        env: &druid::Env,
126    ) -> druid::Size {
127        let mut interactable_area = Region::EMPTY;
128        let smaller_bc = BoxConstraints::new(
129            Size::new(0.0, 0.0),
130            Size::new(bc.max().width - 100.0, bc.max().height - 100.0),
131        );
132        let full_bc = BoxConstraints::new(Size::new(0.0, 0.0), bc.max());
133        let _label_size = self.info_label.layout(ctx, &smaller_bc, data, env);
134        let controls_size = self.controls.layout(ctx, &full_bc, data, env);
135
136        let text_origin_point = Point::new(50.0, 50.0 + controls_size.height);
137        self.info_label.set_origin(ctx, text_origin_point);
138        let controls_origin_point = Point::new(EXAMPLE_BORDER_SIZE, EXAMPLE_BORDER_SIZE);
139        self.controls.set_origin(ctx, controls_origin_point);
140
141        // Add side rects to clarify the dimensions of the window.
142        let left_rect = Rect::new(0.0, 0.0, EXAMPLE_BORDER_SIZE, bc.max().height);
143        let right_rect = Rect::new(
144            bc.max().width - EXAMPLE_BORDER_SIZE,
145            0.0,
146            bc.max().width,
147            bc.max().height,
148        );
149        let bottom_rect = Rect::new(
150            0.0,
151            bc.max().height - EXAMPLE_BORDER_SIZE,
152            bc.max().width,
153            bc.max().height,
154        );
155        interactable_area.add_rect(left_rect);
156        interactable_area.add_rect(right_rect);
157        interactable_area.add_rect(bottom_rect);
158        interactable_area.add_rect(self.info_label.layout_rect());
159        interactable_area.add_rect(self.controls.layout_rect());
160
161        if data.limit_input_region {
162            ctx.window().set_input_region(Some(interactable_area));
163        } else {
164            ctx.window().set_input_region(None);
165        }
166
167        bc.max()
168    }
169
170    fn paint(&mut self, ctx: &mut druid::PaintCtx, data: &AppState, env: &druid::Env) {
171        let window_area = ctx.size();
172        let left_rect = Rect::new(0.0, 0.0, EXAMPLE_BORDER_SIZE, window_area.height);
173        let right_rect = Rect::new(
174            window_area.width - EXAMPLE_BORDER_SIZE,
175            0.0,
176            window_area.width,
177            window_area.height,
178        );
179        let bottom_rect = Rect::new(
180            0.0,
181            window_area.height - EXAMPLE_BORDER_SIZE,
182            window_area.width,
183            window_area.height,
184        );
185
186        ctx.fill(left_rect, &Color::rgba(1.0, 0., 0., 0.7));
187        ctx.fill(right_rect, &Color::rgba(1.0, 0., 0., 0.7));
188        ctx.fill(bottom_rect, &Color::rgba(1.0, 0., 0., 0.7));
189        self.info_label.paint(ctx, data, env);
190        self.controls.paint(ctx, data, env);
191    }
192}
193
194fn main() {
195    let main_window = WindowDesc::new(InputRegionExampleWidget::new())
196        .title("Input Region Demo")
197        .window_size((750.0, 500.0))
198        .with_min_size((650.0, 450.0))
199        // Disable the titlebar since it breaks the desired effect on mac.
200        // It can be turned on with the button, but not on mac.
201        // A lot of apps that will use the interaction features will turn this off
202        // On Windows, if on, this will be invisible, but still there.
203        .show_titlebar(false)
204        .transparent(true);
205
206    let state = AppState {
207        limit_input_region: true,
208        always_on_top: false,
209        show_titlebar: false,
210    };
211
212    AppLauncher::with_window(main_window)
213        .log_to_console()
214        .launch(state)
215        .expect("Failed to launch application");
216}
input_region/input_region.rs

input_region/
input_region.rs
