Expose the application Configuration by reference

This provides an API to access `Configuration` state for the application
without having to make deep copies of the large `Configuration` struct.

This should avoid the need for Winit to create a global static copy of
the Configuration whenever it changes - and instead it can just get
a `ConfigurationRef` which will always reflect the latest config for
the application.

Fixes: #5

android-activity/CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `AndroidApp` is now `Send` + `Sync`
 ### Changed
 - *Breaking*: updates to `ndk 0.7` and `ndk-sys 0.4`
+- *Breaking*: `AndroidApp::config()` now returns a clonable `ConfigurationRef` instead of a deep `Configuration` copy
 
 ## [0.1.1] - 2022-07-04
 ### Changed

android-activity/src/config.rs

@@ -0,0 +1,144 @@
+use core::fmt;
+use std::sync::{Arc, RwLock};
+
+use ndk::configuration::{
+    Configuration, Keyboard, KeysHidden, LayoutDir, NavHidden, Navigation, Orientation, ScreenLong,
+    ScreenSize, Touchscreen, UiModeNight, UiModeType,
+};
+
+#[derive(Clone)]
+pub struct ConfigurationRef {
+    config: Arc<RwLock<Configuration>>,
+}
+impl PartialEq for ConfigurationRef {
+    fn eq(&self, other: &Self) -> bool {
+        if Arc::ptr_eq(&self.config, &other.config) {
+            true
+        } else {
+            let other_guard = other.config.read().unwrap();
+            self.config.read().unwrap().eq(&*other_guard)
+        }
+    }
+}
+impl Eq for ConfigurationRef {}
+unsafe impl Send for ConfigurationRef {}
+unsafe impl Sync for ConfigurationRef {}
+
+impl fmt::Debug for ConfigurationRef {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.config.read().unwrap().fmt(f)
+    }
+}
+
+impl ConfigurationRef {
+    pub(crate) fn new(config: Configuration) -> Self {
+        Self {
+            config: Arc::new(RwLock::new(config)),
+        }
+    }
+
+    pub(crate) fn replace(&self, src: Configuration) {
+        self.config.write().unwrap().copy(&src);
+    }
+
+    // Returns a deep copy of the full application configuration
+    pub fn copy(&self) -> Configuration {
+        let mut dest = Configuration::new();
+        dest.copy(&self.config.read().unwrap());
+        dest
+    }
+    /// Returns the country code, as a [`String`] of two characters, if set
+    pub fn country(&self) -> Option<String> {
+        self.config.read().unwrap().country()
+    }
+
+    /// Returns the screen density in dpi.
+    ///
+    /// On some devices it can return values outside of the density enum.
+    pub fn density(&self) -> Option<u32> {
+        self.config.read().unwrap().density()
+    }
+
+    /// Returns the keyboard type.
+    pub fn keyboard(&self) -> Keyboard {
+        self.config.read().unwrap().keyboard()
+    }
+
+    /// Returns keyboard visibility/availability.
+    pub fn keys_hidden(&self) -> KeysHidden {
+        self.config.read().unwrap().keys_hidden()
+    }
+
+    /// Returns the language, as a `String` of two characters, if a language is set
+    pub fn language(&self) -> Option<String> {
+        self.config.read().unwrap().language()
+    }
+
+    /// Returns the layout direction
+    pub fn layout_direction(&self) -> LayoutDir {
+        self.config.read().unwrap().layout_direction()
+    }
+
+    /// Returns the mobile country code.
+    pub fn mcc(&self) -> i32 {
+        self.config.read().unwrap().mcc()
+    }
+
+    /// Returns the mobile network code, if one is defined
+    pub fn mnc(&self) -> Option<i32> {
+        self.config.read().unwrap().mnc()
+    }
+
+    pub fn nav_hidden(&self) -> NavHidden {
+        self.config.read().unwrap().nav_hidden()
+    }
+
+    pub fn navigation(&self) -> Navigation {
+        self.config.read().unwrap().navigation()
+    }
+
+    pub fn orientation(&self) -> Orientation {
+        self.config.read().unwrap().orientation()
+    }
+
+    pub fn screen_height_dp(&self) -> Option<i32> {
+        self.config.read().unwrap().screen_height_dp()
+    }
+
+    pub fn screen_width_dp(&self) -> Option<i32> {
+        self.config.read().unwrap().screen_width_dp()
+    }
+
+    pub fn screen_long(&self) -> ScreenLong {
+        self.config.read().unwrap().screen_long()
+    }
+
+    #[cfg(feature = "api-level-30")]
+    pub fn screen_round(&self) -> ScreenRound {
+        self.config.read().unwrap().screen_round()
+    }
+
+    pub fn screen_size(&self) -> ScreenSize {
+        self.config.read().unwrap().screen_size()
+    }
+
+    pub fn sdk_version(&self) -> i32 {
+        self.config.read().unwrap().sdk_version()
+    }
+
+    pub fn smallest_screen_width_dp(&self) -> Option<i32> {
+        self.config.read().unwrap().smallest_screen_width_dp()
+    }
+
+    pub fn touchscreen(&self) -> Touchscreen {
+        self.config.read().unwrap().touchscreen()
+    }
+
+    pub fn ui_mode_night(&self) -> UiModeNight {
+        self.config.read().unwrap().ui_mode_night()
+    }
+
+    pub fn ui_mode_type(&self) -> UiModeType {
+        self.config.read().unwrap().ui_mode_type()
+    }
+}

android-activity/src/game_activity/mod.rs

@@ -8,8 +8,7 @@ use std::ops::Deref;
 use std::os::raw;
 use std::os::unix::prelude::*;
 use std::ptr::NonNull;
-use std::sync::Arc;
-use std::sync::RwLock;
+use std::sync::{Arc, RwLock};
 use std::time::Duration;
 use std::{ptr, thread};
 
@@ -25,7 +24,7 @@ use ndk::configuration::Configuration;
 use ndk::looper::FdEvent;
 use ndk::native_window::NativeWindow;
 
-use crate::{util, AndroidApp, MainEvent, NativeWindowRef, PollEvent, Rect};
+use crate::{util, AndroidApp, ConfigurationRef, MainEvent, NativeWindowRef, PollEvent, Rect};
 
 mod ffi;
 
@@ -121,15 +120,12 @@ impl AndroidApp {
         // Note: we don't use from_ptr since we don't own the android_app.config
         // and need to keep in mind that the Drop handler is going to call
         // AConfiguration_delete()
-        //
-        // Whenever we get a ConfigChanged notification we synchronize this
-        // config state with a deep copy.
         let config = Configuration::clone_from_ptr(NonNull::new_unchecked((*ptr.as_ptr()).config));
 
         Self {
             inner: Arc::new(RwLock::new(AndroidAppInner {
                 native_app: NativeAppGlue { ptr },
-                config: RwLock::new(config),
+                config: ConfigurationRef::new(config),
                 native_window: Default::default(),
             })),
         }
@@ -153,7 +149,7 @@ unsafe impl Sync for NativeAppGlue {}
 #[derive(Debug)]
 pub struct AndroidAppInner {
     native_app: NativeAppGlue,
-    config: RwLock<Configuration>,
+    config: ConfigurationRef,
     native_window: RwLock<Option<NativeWindow>>,
 }
 
@@ -254,7 +250,7 @@ impl AndroidAppInner {
                                         MainEvent::LostFocus
                                     }
                                     ffi::NativeAppGlueAppCmd_APP_CMD_CONFIG_CHANGED => {
-                                        MainEvent::ConfigChanged
+                                        MainEvent::ConfigChanged {}
                                     }
                                     ffi::NativeAppGlueAppCmd_APP_CMD_LOW_MEMORY => {
                                         MainEvent::LowMemory
@@ -282,11 +278,10 @@ impl AndroidAppInner {
                                 trace!("Calling android_app_pre_exec_cmd({cmd_i})");
                                 ffi::android_app_pre_exec_cmd(native_app.as_ptr(), cmd_i);
                                 match cmd {
-                                    MainEvent::ConfigChanged => {
-                                        *self.config.write().unwrap() =
-                                            Configuration::clone_from_ptr(NonNull::new_unchecked(
-                                                (*native_app.as_ptr()).config,
-                                            ));
+                                    MainEvent::ConfigChanged { .. } => {
+                                        self.config.replace(Configuration::clone_from_ptr(
+                                            NonNull::new_unchecked((*native_app.as_ptr()).config),
+                                        ));
                                     }
                                     MainEvent::InitWindow { .. } => {
                                         let win_ptr = (*native_app.as_ptr()).window;
@@ -354,8 +349,8 @@ impl AndroidAppInner {
         }
     }
 
-    pub fn config(&self) -> Configuration {
-        self.config.read().unwrap().clone()
+    pub fn config(&self) -> ConfigurationRef {
+        self.config.clone()
     }
 
     pub fn content_rect(&self) -> Rect {

android-activity/src/lib.rs

@@ -5,7 +5,6 @@ use std::time::Duration;
 use std::{os::unix::prelude::RawFd, sync::Arc};
 
 use ndk::asset::AssetManager;
-use ndk::configuration::Configuration;
 // TODO: import FdEvent and avoid depending on ndk Looper abstraction in case we want to
 // support using epoll directly in the future.
 use ndk::looper::FdEvent;
@@ -36,6 +35,9 @@ use game_activity as activity_impl;
 
 pub use activity_impl::input;
 
+mod config;
+pub use config::ConfigurationRef;
+
 mod util;
 
 // Note: unlike in ndk-glue this has signed components (consistent
@@ -148,7 +150,8 @@ pub enum MainEvent<'a> {
     /// Command from main thread: the current device configuration has changed.
     /// You can get a copy of the latest [Configuration] by calling
     /// [`AndroidApp::config()`]
-    ConfigChanged,
+    #[non_exhaustive]
+    ConfigChanged {},
 
     /// Command from main thread: the system is running low on memory.
     /// Try to reduce your memory use.
@@ -267,8 +270,8 @@ impl AndroidApp {
         self.inner.read().unwrap().create_waker()
     }
 
-    /// Returns a deep copy of this application's [`Configuration`]
-    pub fn config(&self) -> Configuration {
+    /// Returns a (cheaply clonable) reference to this application's [`Configuration`]
+    pub fn config(&self) -> ConfigurationRef {
         self.inner.read().unwrap().config()
     }
 

android-activity/src/native_activity/mod.rs

@@ -7,8 +7,7 @@ use std::ops::Deref;
 use std::os::raw;
 use std::os::unix::prelude::*;
 use std::ptr::NonNull;
-use std::sync::Arc;
-use std::sync::RwLock;
+use std::sync::{Arc, RwLock};
 use std::time::Duration;
 use std::{ptr, thread};
 
@@ -23,7 +22,7 @@ use ndk::input_queue::InputQueue;
 use ndk::looper::FdEvent;
 use ndk::native_window::NativeWindow;
 
-use crate::{util, AndroidApp, MainEvent, NativeWindowRef, PollEvent, Rect};
+use crate::{util, AndroidApp, ConfigurationRef, MainEvent, NativeWindowRef, PollEvent, Rect};
 
 mod ffi;
 
@@ -123,15 +122,12 @@ impl AndroidApp {
         // Note: we don't use from_ptr since we don't own the android_app.config
         // and need to keep in mind that the Drop handler is going to call
         // AConfiguration_delete()
-        //
-        // Whenever we get a ConfigChanged notification we synchronize this
-        // config state with a deep copy.
         let config = Configuration::clone_from_ptr(NonNull::new_unchecked((*ptr.as_ptr()).config));
 
         AndroidApp {
             inner: Arc::new(RwLock::new(AndroidAppInner {
                 native_app: NativeAppGlue { ptr },
-                config: RwLock::new(config),
+                config: ConfigurationRef::new(config),
                 native_window: Default::default(),
             })),
         }
@@ -155,7 +151,7 @@ unsafe impl Sync for NativeAppGlue {}
 #[derive(Debug)]
 pub(crate) struct AndroidAppInner {
     native_app: NativeAppGlue,
-    config: RwLock<Configuration>,
+    config: ConfigurationRef,
     native_window: RwLock<Option<NativeWindow>>,
 }
 
@@ -253,7 +249,9 @@ impl AndroidAppInner {
                                     }
                                     ffi::APP_CMD_GAINED_FOCUS => Some(MainEvent::GainedFocus),
                                     ffi::APP_CMD_LOST_FOCUS => Some(MainEvent::LostFocus),
-                                    ffi::APP_CMD_CONFIG_CHANGED => Some(MainEvent::ConfigChanged),
+                                    ffi::APP_CMD_CONFIG_CHANGED => {
+                                        Some(MainEvent::ConfigChanged {})
+                                    }
                                     ffi::APP_CMD_LOW_MEMORY => Some(MainEvent::LowMemory),
                                     ffi::APP_CMD_START => Some(MainEvent::Start),
                                     ffi::APP_CMD_RESUME => Some(MainEvent::Resume {
@@ -276,13 +274,12 @@ impl AndroidAppInner {
                                 if let Some(cmd) = cmd {
                                     trace!("Read ID_MAIN command {cmd_i} = {cmd:?}");
                                     match cmd {
-                                        MainEvent::ConfigChanged => {
-                                            *self.config.write().unwrap() =
-                                                Configuration::clone_from_ptr(
-                                                    NonNull::new_unchecked(
-                                                        (*native_app.as_ptr()).config,
-                                                    ),
-                                                );
+                                        MainEvent::ConfigChanged { .. } => {
+                                            self.config.replace(Configuration::clone_from_ptr(
+                                                NonNull::new_unchecked(
+                                                    (*native_app.as_ptr()).config,
+                                                ),
+                                            ));
                                         }
                                         MainEvent::InitWindow { .. } => {
                                             let win_ptr = (*native_app.as_ptr()).window;
@@ -353,8 +350,8 @@ impl AndroidAppInner {
         }
     }
 
-    pub fn config(&self) -> Configuration {
-        self.config.read().unwrap().clone()
+    pub fn config(&self) -> ConfigurationRef {
+        self.config.clone()
     }
 
     pub fn content_rect(&self) -> Rect {

examples/agdk-mainloop/src/lib.rs

@@ -52,6 +52,9 @@ fn android_main(app: AndroidApp) {
                             MainEvent::InputAvailable { .. } => {
                                 redraw_pending = true;
                             }
+                            MainEvent::ConfigChanged { .. } => {
+                                info!("Config Changed: {:#?}", app.config());
+                            }
                             MainEvent::LowMemory => {}
 
                             MainEvent::Destroy => quit = true,

examples/na-mainloop/.idea/gradle.xml

@@ -13,7 +13,6 @@
             <option value="$PROJECT_DIR$/app" />
           </set>
         </option>
-        <option name="resolveModulePerSourceSet" value="false" />
       </GradleProjectSettings>
     </option>
   </component>

examples/na-mainloop/src/lib.rs

@@ -52,6 +52,9 @@ fn android_main(app: AndroidApp) {
                             MainEvent::InputAvailable { .. } => {
                                 redraw_pending = true;
                             }
+                            MainEvent::ConfigChanged { .. } => {
+                                info!("Config Changed: {:#?}", app.config());
+                            }
                             MainEvent::LowMemory => {}
 
                             MainEvent::Destroy => quit = true,