| Bring vidya in cfd3e36 nandi 19d ago | 1 | //! System chrome (status bar / nav bar) safe areas. |
| 2 | //! |
| 3 | //! Android NativeActivity draws **edge-to-edge**: the window fills under the |
| 4 | //! system status bar (clock, battery, …) and the gesture/nav bar. Without an |
| 5 | //! explicit reserve, app chrome and labels sit under those system widgets. |
| 6 | //! |
| 7 | //! Call [`reserve_system_chrome`] once at the start of every frame (before any |
| 8 | //! other `TopBottomPanel` / `SidePanel` / `CentralPanel`), or use |
| 9 | //! [`top_header`] which does that for you. |
| 10 | //! |
| 11 | //! Prefer injecting measured insets via [`set_system_chrome`] or |
| 12 | //! [`sync_system_chrome_from_android`] (from `AndroidApp::content_rect` or |
| 13 | //! WindowInsets) so reserves match the device — hardcoded fallbacks are |
| 14 | //! intentionally tight for modern gesture-nav phones. |
| 15 | |
| 16 | use egui::{Align2, Context, Frame, Id, Margin, Sense, Ui, WidgetText, Window}; |
| 17 | |
| 18 | use crate::Theme; |
| 19 | |
| 20 | /// Temp-data id for app-supplied measured insets (see [`set_system_chrome`]). |
| 21 | const SYSTEM_CHROME_ID: &str = "vidya.system_chrome"; |
| 22 | /// Last measured nav-band height when the keyboard was hidden. |
| 23 | const NAV_HINT_ID: &str = "vidya.nav_bottom_hint"; |
| 24 | |
| 25 | /// Insets for system status / navigation chrome on edge-to-edge surfaces. |
| 26 | #[derive(Debug, Clone, Copy, PartialEq)] |
| 27 | pub struct SystemChrome { |
| 28 | /// Space under the status bar (clock, indicators). |
| 29 | pub top: f32, |
| 30 | /// Space above the system gesture / 3-button nav bar. |
| 31 | pub nav_bottom: f32, |
| 32 | /// Extra reserve when the soft keyboard is visible (sits above [`nav_bottom`]). |
| 33 | pub ime_bottom: f32, |
| 34 | } |
| 35 | |
| 36 | impl SystemChrome { |
| 37 | pub const ZERO: Self = Self { |
| 38 | top: 0.0, |
| 39 | nav_bottom: 0.0, |
| 40 | ime_bottom: 0.0, |
| 41 | }; |
| 42 | |
| 43 | /// Combined bottom inset (nav + IME). |
| 44 | #[inline] |
| 45 | pub fn bottom(self) -> f32 { |
| 46 | self.nav_bottom + self.ime_bottom |
| 47 | } |
| 48 | |
| 49 | pub fn is_zero(self) -> bool { |
| 50 | self.top <= 0.0 && self.bottom() <= 0.0 |
| 51 | } |
| 52 | |
| 53 | /// Build from status + nav insets (no IME reserve). |
| 54 | pub fn from_insets(top: f32, nav_bottom: f32) -> Self { |
| 55 | Self { |
| 56 | top: top.max(0.0), |
| 57 | nav_bottom: nav_bottom.max(0.0), |
| 58 | ime_bottom: 0.0, |
| 59 | } |
| 60 | } |
| 61 | } |
| 62 | |
| 63 | /// Inject measured system insets for this frame (egui points). |
| 64 | /// |
| 65 | /// Call once per frame **before** [`reserve_system_chrome`]. When set, |
| 66 | /// [`system_chrome`] uses these values instead of the platform fallbacks and |
| 67 | /// does **not** add focus-based IME padding on top (measured insets already |
| 68 | /// reflect keyboard visibility from `content_rect` / WindowInsets). |
| 69 | pub fn set_system_chrome(ctx: &Context, chrome: SystemChrome) { |
| 70 | ctx.data_mut(|d| d.insert_temp(Id::new(SYSTEM_CHROME_ID), chrome)); |
| 71 | } |
| 72 | |
| 73 | /// Read measured insets from [`AndroidApp::content_rect`] and call |
| 74 | /// [`set_system_chrome`]. |
| 75 | /// |
| 76 | /// Call once per frame on Android **before** [`reserve_system_chrome`]. When the |
| 77 | /// soft keyboard is open, `content_rect` shrinks and the derived bottom inset |
| 78 | /// includes the IME height so layout tracks the real keyboard band — even when |
| 79 | /// the user dismisses the keyboard via the IME close button while a text field |
| 80 | /// still holds focus. |
| 81 | #[cfg(target_os = "android")] |
| 82 | pub fn sync_system_chrome_from_android( |
| 83 | ctx: &Context, |
| 84 | app: &winit::platform::android::activity::AndroidApp, |
| 85 | ) { |
| 86 | const NAV_FALLBACK: f32 = 20.0; |
| 87 | /// Minimum extra inset beyond the nav band before treating the IME as visible. |
| 88 | const IME_VISIBLE_THRESHOLD: f32 = 48.0; |
| 89 | |
| 90 | let rect = app.content_rect(); |
| 91 | let ppp = ctx.pixels_per_point().max(0.01); |
| 92 | let screen = ctx.screen_rect(); |
| 93 | |
| 94 | let top = (rect.top as f32 / ppp).max(0.0); |
| 95 | let content_bottom_pt = rect.bottom as f32 / ppp; |
| 96 | let total_bottom = (screen.height() - content_bottom_pt).max(0.0); |
| 97 | |
| 98 | let nav_hint = ctx |
| 99 | .data(|d| d.get_temp::<f32>(Id::new(NAV_HINT_ID))) |
| 100 | .unwrap_or(NAV_FALLBACK); |
| 101 | |
| 102 | // Derive keyboard visibility from content_rect, not wants_keyboard_input(): |
| 103 | // dismissing the IME hides the keyboard but often leaves text focus. |
| 104 | let keyboard_visible = total_bottom > nav_hint + IME_VISIBLE_THRESHOLD; |
| 105 | |
| 106 | if keyboard_visible { |
| 107 | let nav = nav_hint.clamp(0.0, total_bottom); |
| 108 | set_system_chrome( |
| 109 | ctx, |
| 110 | SystemChrome { |
| 111 | top, |
| 112 | nav_bottom: nav, |
| 113 | ime_bottom: (total_bottom - nav).max(0.0), |
| 114 | }, |
| 115 | ); |
| 116 | } else { |
| 117 | ctx.data_mut(|d| d.insert_temp(Id::new(NAV_HINT_ID), total_bottom)); |
| 118 | set_system_chrome(ctx, SystemChrome::from_insets(top, total_bottom)); |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | /// Platform defaults for edge-to-edge drawing. |
| 123 | /// |
| 124 | /// Fallback values are **tight** for modern gesture-nav phones (≈24–28 dp |
| 125 | /// status, ≈16–24 dp gesture handle). Prefer [`set_system_chrome`] or |
| 126 | /// [`sync_system_chrome_from_android`] with measured `content_rect` / |
| 127 | /// WindowInsets when available. |
| 128 | /// |
| 129 | /// When a text field holds focus (`Context::wants_keyboard_input`), the bottom |
| 130 | /// inset grows so bottom bars / compose fields sit **above** the soft keyboard |
| 131 | /// (NativeActivity rarely resizes the GL surface for IME). |
| 132 | pub fn system_chrome(ctx: &Context) -> SystemChrome { |
| 133 | #[cfg(target_os = "android")] |
| 134 | { |
| 135 | let measured = ctx.data(|d| d.get_temp::<SystemChrome>(Id::new(SYSTEM_CHROME_ID))); |
| 136 | const TOP_FALLBACK: f32 = 36.0; |
| 137 | const NAV_FALLBACK: f32 = 20.0; |
| 138 | let top = match measured { |
| 139 | Some(c) if c.top >= 8.0 => c.top, |
| 140 | Some(c) => c.top.max(TOP_FALLBACK), |
| 141 | None => TOP_FALLBACK, |
| 142 | }; |
| 143 | |
| 144 | if let Some(m) = measured { |
| 145 | let chrome = SystemChrome { |
| 146 | top, |
| 147 | nav_bottom: m.nav_bottom.max(0.0), |
| 148 | ime_bottom: m.ime_bottom.max(0.0), |
| 149 | }; |
| 150 | // content_rect / WindowInsets may still be animating with the IME. |
| 151 | if chrome.ime_bottom > NAV_FALLBACK { |
| 152 | ctx.request_repaint(); |
| 153 | } |
| 154 | return chrome; |
| 155 | } |
| 156 | |
| 157 | let mut nav_bottom = NAV_FALLBACK; |
| 158 | let mut ime_bottom = 0.0; |
| 159 | |
| 160 | if ctx.wants_keyboard_input() { |
| 161 | let h = ctx.screen_rect().height(); |
| 162 | let ime_fallback = (h * 0.40).clamp(240.0, h * 0.52); |
| 163 | nav_bottom = NAV_FALLBACK.min(ime_fallback); |
| 164 | ime_bottom = (ime_fallback - nav_bottom).max(0.0); |
| 165 | ctx.request_repaint(); |
| 166 | } |
| 167 | |
| 168 | SystemChrome { |
| 169 | top, |
| 170 | nav_bottom, |
| 171 | ime_bottom, |
| 172 | } |
| 173 | } |
| 174 | #[cfg(not(target_os = "android"))] |
| 175 | { |
| 176 | let _ = ctx; |
| 177 | SystemChrome::ZERO |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | /// Reserve top/bottom strips so **no** subsequent panel or central content can |
| 182 | /// paint under the system status or navigation bars. |
| 183 | /// |
| 184 | /// Call this **once per frame**, before other panels. Safe to call when insets |
| 185 | /// are zero (no-op on desktop). |
| 186 | /// |
| 187 | /// When the soft keyboard is open, the IME reserve does **not** absorb pointer |
| 188 | /// events so swipe typing on the system keyboard is not blocked. Only the nav |
| 189 | /// strip keeps a hover sink so widgets behind the gesture bar cannot steal taps. |
| 190 | pub fn reserve_system_chrome(ctx: &Context, theme: &Theme) { |
| 191 | let chrome = system_chrome(ctx); |
| 192 | if chrome.is_zero() { |
| 193 | return; |
| 194 | } |
| 195 | |
| 196 | let top_band = Frame::new() |
| 197 | .fill(theme.palette.headerbar_bg) |
| 198 | .inner_margin(Margin::ZERO); |
| 199 | let nav_band = Frame::new() |
| 200 | .fill(theme.palette.window_bg) |
| 201 | .inner_margin(Margin::ZERO); |
| 202 | // Transparent — only reserves layout; must not paint over the IME. |
| 203 | let ime_band = Frame::NONE; |
| 204 | |
| 205 | if chrome.top > 0.0 { |
| 206 | egui::TopBottomPanel::top("vidya_system_chrome_top") |
| 207 | .exact_height(chrome.top) |
| 208 | .frame(top_band) |
| 209 | .show_separator_line(false) |
| 210 | .show(ctx, |_ui| {}); |
| 211 | } |
| 212 | |
| 213 | // Bottom panels stack upward: declare nav first (screen edge), then IME. |
| 214 | if chrome.nav_bottom > 0.0 { |
| 215 | egui::TopBottomPanel::bottom("vidya_system_chrome_nav") |
| 216 | .exact_height(chrome.nav_bottom) |
| 217 | .frame(nav_band) |
| 218 | .show_separator_line(false) |
| 219 | .show(ctx, |ui| { |
| 220 | ui.allocate_exact_size(ui.available_size(), Sense::hover()); |
| 221 | }); |
| 222 | } |
| 223 | |
| 224 | if chrome.ime_bottom > 0.0 { |
| 225 | egui::TopBottomPanel::bottom("vidya_system_chrome_ime") |
| 226 | .exact_height(chrome.ime_bottom) |
| 227 | .frame(ime_band) |
| 228 | .show_separator_line(false) |
| 229 | .show(ctx, |ui| { |
| 230 | // Pass touches through to the system keyboard (swipe / glide typing). |
| 231 | ui.allocate_exact_size(ui.available_size(), Sense::empty()); |
| 232 | }); |
| 233 | } |
| 234 | } |
| 235 | |
| 236 | /// Top app header with system status bar already reserved. |
| 237 | /// |
| 238 | /// Preferred entry for shell chrome: apps cannot place title/status text under |
| 239 | /// the clock / indicators. Also reserves the bottom system nav band. |
| 240 | /// |
| 241 | /// ```ignore |
| 242 | /// vidya::top_header(ctx, &theme, |ui| { |
| 243 | /// ui.horizontal(|ui| { |
| 244 | /// vidya::title(ui, &theme, "My App"); |
| 245 | /// }); |
| 246 | /// }); |
| 247 | /// ``` |
| 248 | pub fn top_header(ctx: &Context, theme: &Theme, add_contents: impl FnOnce(&mut Ui)) { |
| 249 | reserve_system_chrome(ctx, theme); |
| 250 | egui::TopBottomPanel::top("vidya_app_header") |
| 251 | .frame(theme.header_frame()) |
| 252 | .show_separator_line(false) |
| 253 | .show(ctx, add_contents); |
| 254 | } |
| 255 | |
| 256 | /// Centered modal-style window with themed card chrome. |
| 257 | /// |
| 258 | /// Defaults: non-collapsible, **resizable**, centered, [`Theme::card_frame`]. |
| 259 | /// Chain `.default_size` / `.min_width` / `.resizable(false)` as needed, then |
| 260 | /// `.show`. |
| 261 | /// |
| 262 | /// ```ignore |
| 263 | /// vidya::dialog("Rename", &theme) |
| 264 | /// .default_width(360.0) |
| 265 | /// .min_width(280.0) |
| 266 | /// .show(ctx, |ui| { /* … */ }); |
| 267 | /// ``` |
| 268 | pub fn dialog<'a>(title: impl Into<WidgetText> + 'a, theme: &Theme) -> Window<'a> { |
| 269 | Window::new(title) |
| 270 | .collapsible(false) |
| 271 | .resizable(true) |
| 272 | .anchor(Align2::CENTER_CENTER, [0.0, 0.0]) |
| 273 | .frame(theme.card_frame()) |
| 274 | } |
| 275 | |
| 276 | #[cfg(test)] |
| 277 | mod tests { |
| 278 | use super::*; |
| 279 | |
| 280 | #[test] |
| 281 | fn system_chrome_bottom_sums_nav_and_ime() { |
| 282 | let c = SystemChrome { |
| 283 | top: 36.0, |
| 284 | nav_bottom: 20.0, |
| 285 | ime_bottom: 400.0, |
| 286 | }; |
| 287 | assert!((c.bottom() - 420.0).abs() < f32::EPSILON); |
| 288 | assert!(!c.is_zero()); |
| 289 | } |
| 290 | |
| 291 | #[test] |
| 292 | fn from_insets_zeroes_ime() { |
| 293 | let c = SystemChrome::from_insets(36.0, 20.0); |
| 294 | assert_eq!(c.ime_bottom, 0.0); |
| 295 | assert_eq!(c.nav_bottom, 20.0); |
| 296 | } |
| 297 | } |