unity-tidbits/application/ApplicationChrome.cs

#if UNITY_ANDROID && !UNITY_EDITOR
#define USE_ANDROID
#endif

using System;
using System.Collections.Generic;
using UnityEngine;

/**
 * @author zeh fernando
 */
class ApplicationChrome {

	/**
	 * Manipulates the system application chrome to change the way the status bar and navigation bar work
	 *
	 * References:
	 * . http://developer.android.com/reference/android/view/View.html#setSystemUiVisibility(int)
	 * . http://forum.unity3d.com/threads/calling-setsystemuivisibility.139445/#post-952946
	 * . http://developer.android.com/reference/android/view/WindowManager.LayoutParams.html#FLAG_LAYOUT_IN_SCREEN
	 **/

	// Enums
	public enum States {
		Unknown,
		Visible,
		VisibleOverContent,
		TranslucentOverContent,
		Hidden
	}

	// Constants
	private const uint DEFAULT_BACKGROUND_COLOR = 0xff000000;

	#if USE_ANDROID
		// Original Android flags
		private const int VIEW_SYSTEM_UI_FLAG_VISIBLE = 0;					// Added in API 14 (Android 4.0.x): Status bar visible (the default)
		private const int VIEW_SYSTEM_UI_FLAG_LOW_PROFILE = 1;				// Added in API 14 (Android 4.0.x): Low profile for games, book readers, and video players; the status bar and/or navigation icons are dimmed out (if visible)
		private const int VIEW_SYSTEM_UI_FLAG_HIDE_NAVIGATION = 2;			// Added in API 14 (Android 4.0.x): Hides all navigation. Cleared when theres any user interaction.
		private const int VIEW_SYSTEM_UI_FLAG_FULLSCREEN = 4;				// Added in API 16 (Android 4.1.x): Hides status bar. Does nothing in Unity (already hidden if "status bar hidden" is checked)
		private const int VIEW_SYSTEM_UI_FLAG_LAYOUT_STABLE = 256;			// Added in API 16 (Android 4.1.x): ?
		private const int VIEW_SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION = 512;	// Added in API 16 (Android 4.1.x): like HIDE_NAVIGATION, but for layouts? it causes the layout to be drawn like that, even if the whole view isn't (to avoid artifacts in animation)
		private const int VIEW_SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN = 1024;		// Added in API 16 (Android 4.1.x): like FULLSCREEN, but for layouts? it causes the layout to be drawn like that, even if the whole view isn't (to avoid artifacts in animation)
		private const int VIEW_SYSTEM_UI_FLAG_IMMERSIVE = 2048;				// Added in API 19 (Android 4.4): like HIDE_NAVIGATION, but interactive (it's a modifier for HIDE_NAVIGATION, needs to be used with it)
		private const int VIEW_SYSTEM_UI_FLAG_IMMERSIVE_STICKY = 4096;		// Added in API 19 (Android 4.4): tells that HIDE_NAVIGATION and FULSCREEN are interactive (also just a modifier)

		private static int WINDOW_FLAG_FULLSCREEN = 0x00000400;
		private static int WINDOW_FLAG_FORCE_NOT_FULLSCREEN = 0x00000800;
		private static int WINDOW_FLAG_LAYOUT_IN_SCREEN = 0x00000100;
		private static int WINDOW_FLAG_TRANSLUCENT_STATUS = 0x04000000;
		private static int WINDOW_FLAG_TRANSLUCENT_NAVIGATION = 0x08000000;
		private static int WINDOW_FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS = -2147483648; // 0x80000000; // Added in API 21 (Android 5.0): tells the Window is responsible for drawing the background for the system bars. If set, the system bars are drawn with a transparent background and the corresponding areas in this window are filled with the colors specified in getStatusBarColor() and getNavigationBarColor()

		// Current values
		private static int systemUiVisibilityValue;
		private static int flagsValue;
	#endif

	// Properties
	private static States _statusBarState;
	private static States _navigationBarState;

	private static uint _statusBarColor = DEFAULT_BACKGROUND_COLOR;
	private static uint _navigationBarColor = DEFAULT_BACKGROUND_COLOR;

	private static bool _isStatusBarTranslucent; // Just so we know whether its translucent when hidden or not
	private static bool _isNavigationBarTranslucent;

	private static bool _dimmed;


	// ================================================================================================================
	// INTERNAL INTERFACE ---------------------------------------------------------------------------------------------

	static ApplicationChrome() {
		applyUIStates();
		applyUIColors();
	}

	private static void applyUIStates() {
		#if USE_ANDROID
			applyUIStatesAndroid();
		#endif
	}

	private static void applyUIColors() {
		#if USE_ANDROID
			applyUIColorsAndroid();
		#endif
	}

	#if USE_ANDROID

		private static void applyUIStatesAndroid() {
			int newFlagsValue = 0;
			int newSystemUiVisibilityValue = 0;

			// Apply dim values
			if (_dimmed) newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_LOW_PROFILE;

			// Apply color values
			if (_navigationBarColor != DEFAULT_BACKGROUND_COLOR || _statusBarColor != DEFAULT_BACKGROUND_COLOR) newFlagsValue |= WINDOW_FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS;

			// Apply status bar values
			switch (_statusBarState) {
				case States.Visible:
					_isStatusBarTranslucent = false;
					newFlagsValue |= WINDOW_FLAG_FORCE_NOT_FULLSCREEN;
					break;
				case States.VisibleOverContent:
					_isStatusBarTranslucent = false;
					newFlagsValue |= WINDOW_FLAG_FORCE_NOT_FULLSCREEN | WINDOW_FLAG_LAYOUT_IN_SCREEN;
					newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN;
					break;
				case States.TranslucentOverContent:
					_isStatusBarTranslucent = true;
					newFlagsValue |= WINDOW_FLAG_FORCE_NOT_FULLSCREEN | WINDOW_FLAG_LAYOUT_IN_SCREEN | WINDOW_FLAG_TRANSLUCENT_STATUS;
					newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN;
					break;
				case States.Hidden:
					newFlagsValue |= WINDOW_FLAG_FULLSCREEN | WINDOW_FLAG_LAYOUT_IN_SCREEN;
					if (_isStatusBarTranslucent) newFlagsValue |= WINDOW_FLAG_TRANSLUCENT_STATUS;
					break;
			}

			// Applies navigation values
			switch (_navigationBarState) {
				case States.Visible:
					_isNavigationBarTranslucent = false;
					newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_LAYOUT_STABLE;
					break;
				case States.VisibleOverContent:
					// TODO: Side effect: forces status bar over content if set to VISIBLE
					_isNavigationBarTranslucent = false;
					newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_LAYOUT_STABLE | VIEW_SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION;
					break;
				case States.TranslucentOverContent:
					// TODO: Side effect: forces status bar over content if set to VISIBLE
					_isNavigationBarTranslucent = true;
					newFlagsValue |= WINDOW_FLAG_TRANSLUCENT_NAVIGATION;
					newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_LAYOUT_STABLE | VIEW_SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION;
					break;
				case States.Hidden:
					newSystemUiVisibilityValue |= VIEW_SYSTEM_UI_FLAG_FULLSCREEN | VIEW_SYSTEM_UI_FLAG_HIDE_NAVIGATION | VIEW_SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
					if (_isNavigationBarTranslucent) newFlagsValue |= WINDOW_FLAG_TRANSLUCENT_NAVIGATION;
					break;
			}

			if (Screen.fullScreen) Screen.fullScreen = false;

			// Applies everything natively
			setFlags(newFlagsValue);
			setSystemUiVisibility(newSystemUiVisibilityValue);
		}

		private static void runOnAndroidUiThread(Action target) {
			using (var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer")) {
				using (var activity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity")) {
					activity.Call("runOnUiThread", new AndroidJavaRunnable(target));
				}
			}
		}

		private static void setSystemUiVisibility(int value) {
			if (systemUiVisibilityValue != value) {
				systemUiVisibilityValue = value;
				runOnAndroidUiThread(setSystemUiVisibilityInThread);
			}
		}

		private static void setSystemUiVisibilityInThread() {
			using (var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer")) {
				using (var activity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity")) {
					using (var window = activity.Call<AndroidJavaObject>("getWindow")) {
						using (var view = window.Call<AndroidJavaObject>("getDecorView")) {
							// We also remove the existing listener. It seems Unity uses it internally
							// to detect changes to the visibility flags, and re-apply its own changes.
							// For example, if we hide the navigation bar, it shows up again 1 sec later.
							view.Call("setOnSystemUiVisibilityChangeListener", null);
							view.Call("setSystemUiVisibility", systemUiVisibilityValue);
						}
					}
				}
			}
		}

		private static void setFlags(int value) {
			if (flagsValue != value) {
				flagsValue = value;
				runOnAndroidUiThread(setFlagsInThread);
			}
		}

		private static void setFlagsInThread() {
			using (var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer")) {
				using (var activity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity")) {
					using (var window = activity.Call<AndroidJavaObject>("getWindow")) {
						window.Call("setFlags", flagsValue, -1); // (int)0x7FFFFFFF
					}
				}
			}
		}

		private static void applyUIColorsAndroid() {
			runOnAndroidUiThread(applyUIColorsAndroidInThread);
		}

		private static void applyUIColorsAndroidInThread() {
			using (var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer")) {
				using (var activity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity")) {
					using (var window = activity.Call<AndroidJavaObject>("getWindow")) {
						//Debug.Log("Colors SET: " + _statusBarColor);
						window.Call("setStatusBarColor", unchecked((int)_statusBarColor));
						window.Call("setNavigationBarColor", unchecked((int)_navigationBarColor));
					}
				}
			}
		}

	#endif

	// ================================================================================================================
	// ACCESSOR INTERFACE ---------------------------------------------------------------------------------------------

	public static States navigationBarState {
		get { return _navigationBarState; }
		set {
			if (_navigationBarState != value) {
				_navigationBarState = value;
				applyUIStates();
			}
		}
	}

	public static States statusBarState {
		get { return _statusBarState; }
		set {
			if (_statusBarState != value) {
				_statusBarState = value;
				applyUIStates();
			}
		}
	}

	public static bool dimmed {
		get { return _dimmed; }
		set {
			if (_dimmed != value) {
				_dimmed = value;
				applyUIStates();
			}
		}
	}

	public static uint statusBarColor {
		get { return _statusBarColor; }
		set {
			if (_statusBarColor != value) {
				_statusBarColor = value;
				applyUIColors();
				applyUIStates();
			}
		}
	}

	public static uint navigationBarColor {
		get { return _navigationBarColor; }
		set {
			if (_navigationBarColor != value) {
				_navigationBarColor = value;
				applyUIColors();
				applyUIStates();
			}
		}
	}
}