livecode · livecodepanos · Apr 7, 2020 · Mar 20, 2020 · livecodepanos · Apr 14, 2020
diff --git a/docs/dictionary/message/systemAppearanceChanged.lcdoc b/docs/dictionary/message/systemAppearanceChanged.lcdoc
@@ -0,0 +1,35 @@
+Name: systemAppearanceChanged
+
+Type: message
+
+Syntax: systemAppearanceChanged
+
+Summary:
+Sent to the <current card> of the <defaultStack> when the <system appearance|systemAppearance>
+changes.
+
+Associations: card
+
+Introduced: 1.0
+
+OS: mac, ios, android
+
+Platforms: desktop,mobile
+
+Example:
+on systemAppearanceChanged
+    if the systemAppearance is "dark" then
+        set the backColor of me to "black"
+        set the foreColor of me to "white"
+    else
+        set the backColor of me to "white"
+        set the foreColor of me to "black"
+    end if
+on systemAppearanceChanged
+
+Description:
+Handle the <systemAppearanceChanged> <message> if you need to change the color
+of objects when the application enters either light or dark mode.
+
+References: systemAppearance (property), message (glossary), defaultStack (property)
+
diff --git a/docs/dictionary/property/systemAppearance.lcdoc b/docs/dictionary/property/systemAppearance.lcdoc
@@ -0,0 +1,30 @@
+Name: systemAppearance
+
+Type: property
+
+Syntax: get the systemAppearance
+
+Summary:
+Determins if the system appearance is dark or light mode. 
+
+Introduced: 9.6
+
+OS: mac, android, ios
+
+Platforms: desktop, mobile
+
+Example:
+if the systemAppearance is "dark" then
+    set the backColor of me to "black"
+    set the foreColor of me to "white"
+else
+    set the backColor of me to "white"
+    set the foreColor of me to "black"
+end if
+
+Description:
+The <systemAppearance> property returns either "dark" or "light" depending on
+whether the application is running in a dark mode context or not. On windows
+and linux the property will return "light".
+
+References: systemAppearanceChanged (message)
diff --git a/docs/notes/bugfix-22607.md b/docs/notes/bugfix-22607.md
@@ -0,0 +1,7 @@
+# Dark mode detection
+
+A new `systemAppearance` property has been added which returns `dark` if
+the application is running in dark mode and `light` otherwise.
+
+A new `systemAppearanceChanged` message is now sent to the current card of the
+defaultStack when the system appearance changes.
diff --git a/engine/src/desktop-dc.cpp b/engine/src/desktop-dc.cpp
@@ -944,6 +944,13 @@ void MCScreenDC::closeIME()
 
 ////////////////////////////////////////////////////////////////////////////////
 
+void MCScreenDC::getsystemappearance(MCSystemAppearance &r_appearance)
+{
+	MCPlatformGetSystemProperty(kMCPlatformSystemPropertySystemAppearance, kMCPlatformPropertyTypeInt32, &r_appearance);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 extern bool MCListSystemPrinters(MCStringRef &);
 extern MCPrinter *MCCreateSystemPrinter(void);
 

diff --git a/engine/src/desktop-dc.h b/engine/src/desktop-dc.h
@@ -142,7 +142,9 @@ class MCScreenDC: public MCUIDC
 
     // MW-2014-04-26: [[ Bug 5545 ]] Override this method to defer to the MCPlatform method.
     virtual void hidecursoruntilmousemoves(void);
-
+
+	virtual void getsystemappearance(MCSystemAppearance &r_appearance);
+
 	//////////
 
 	bool isbackdrop(MCPlatformWindowRef window);

diff --git a/engine/src/desktop.cpp b/engine/src/desktop.cpp
@@ -164,6 +164,16 @@ void MCPlatformHandleScreenParametersChanged(void)
 
 ////////////////////////////////////////////////////////////////////////////////
 
+void MCPlatformHandleSystemAppearanceChanged(void)
+{
+	if (MCscreen == nil)
+		return;
+
+	MCscreen -> delaymessage(MCdefaultstackptr -> getcurcard(), MCM_system_appearance_changed);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 #if defined (FEATURE_PLATFORM_WINDOW)
 void MCPlatformHandleWindowCloseRequest(MCPlatformWindowRef p_window)
 {

diff --git a/engine/src/exec-interface2.cpp b/engine/src/exec-interface2.cpp
@@ -432,6 +432,21 @@ static MCExecEnumTypeInfo _kMCInterfaceSelectionModeTypeInfo =
 	_kMCInterfaceSelectionModeElementInfo,
 };
 
+//////////
+
+static MCExecEnumTypeElementInfo _kMCInterfaceSystemAppearanceElementInfo[] =
+{
+	{ "light", 0, false },
+	{ "dark", 1, false },
+};
+
+static MCExecEnumTypeInfo _kMCInterfaceSystemAppearanceTypeInfo =
+{
+	"Interface.ProcessType",
+	sizeof(_kMCInterfaceSystemAppearanceElementInfo) / sizeof(MCExecEnumTypeElementInfo),
+	_kMCInterfaceSystemAppearanceElementInfo,
+};
+
 ////////////////////////////////////////////////////////////////////////////////
 
 MCExecEnumTypeInfo *kMCInterfaceLookAndFeelTypeInfo = &_kMCInterfaceLookAndFeelTypeInfo;
@@ -441,6 +456,7 @@ MCExecEnumTypeInfo *kMCInterfacePaintCompressionTypeInfo = &_kMCInterfacePaintCo
 MCExecEnumTypeInfo *kMCInterfaceProcessTypeTypeInfo = &_kMCInterfaceProcessTypeTypeInfo;
 MCExecEnumTypeInfo *kMCInterfaceSelectionModeTypeInfo = &_kMCInterfaceSelectionModeTypeInfo;
 MCExecCustomTypeInfo *kMCInterfaceStackFileVersionTypeInfo = &_kMCInterfaceStackFileVersionTypeInfo;
+MCExecEnumTypeInfo *kMCInterfaceSystemAppearanceTypeInfo = &_kMCInterfaceSystemAppearanceTypeInfo;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -1701,6 +1717,13 @@ void MCInterfaceSetSelectionMode(MCExecContext& ctxt, intenum_t p_value)
 	MCselectintersect = (Boolean)p_value;
 }
 
+void MCInterfaceGetSystemAppearance(MCExecContext& ctxt, intenum_t& r_value)
+{
+	MCSystemAppearance t_appearance;
+	MCscreen->getsystemappearance(t_appearance);
+	r_value = (intenum_t)t_appearance;
+}
+
 void MCInterfaceGetSelectionHandleColor(MCExecContext& ctxt, MCInterfaceNamedColor& r_color)
 {
 	get_interface_color(MCselectioncolor, MCselectioncolorname, r_color);

diff --git a/engine/src/exec.h b/engine/src/exec.h
@@ -2182,6 +2182,7 @@ extern MCExecCustomTypeInfo *kMCInterfaceVisualEffectArgumentTypeInfo;
 extern MCExecCustomTypeInfo *kMCInterfaceButtonIconTypeInfo;
 extern MCExecCustomTypeInfo *kMCInterfaceTriStateTypeInfo;
 extern MCExecCustomTypeInfo *kMCInterfaceStackFileVersionTypeInfo;
+extern MCExecEnumTypeInfo *kMCInterfaceSystemAppearanceTypeInfo;
 
 void MCInterfaceInitialize(MCExecContext& ctxt);
 void MCInterfaceFinalize(MCExecContext& ctxt);
@@ -2645,6 +2646,7 @@ void MCInterfaceGetScreenGamma(MCExecContext& ctxt, double& r_value);
 void MCInterfaceSetScreenGamma(MCExecContext& ctxt, double p_value);
 void MCInterfaceGetSelectionMode(MCExecContext& ctxt, intenum_t& r_value);
 void MCInterfaceSetSelectionMode(MCExecContext& ctxt, intenum_t p_value);
+void MCInterfaceGetSystemAppearance(MCExecContext& ctxt, intenum_t& r_value);
 void MCInterfaceGetSelectionHandleColor(MCExecContext& ctxt, MCInterfaceNamedColor& r_color);
 void MCInterfaceSetSelectionHandleColor(MCExecContext& ctxt, const MCInterfaceNamedColor& p_color);
 void MCInterfaceGetWindowBoundingRect(MCExecContext& ctxt, MCRectangle& r_value);

diff --git a/engine/src/java/com/runrev/android/Engine.java b/engine/src/java/com/runrev/android/Engine.java
@@ -138,6 +138,8 @@ public class Engine extends View implements EngineApi
 	private boolean m_new_intent;
 
 	private int m_photo_width, m_photo_height;
+
+	private int m_night_mode;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -239,6 +241,10 @@ public void onScreenOrientationChanged(int orientation)
 
 		m_photo_width = 0;
 		m_photo_height = 0;
+
+		m_night_mode =
+			p_context.getResources().getConfiguration().uiMode &
+			Configuration.UI_MODE_NIGHT_MASK;
 	}
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -356,6 +362,15 @@ public String loadExternalLibrary(String name)
 
     public void onConfigurationChanged(Configuration p_new_config)
 	{
+		int t_night_mode =
+			getContext().getResources().getConfiguration().uiMode &
+			Configuration.UI_MODE_NIGHT_MASK;
+
+		if (t_night_mode != m_night_mode)
+		{
+			m_night_mode = t_night_mode;
+			doSystemAppearanceChanged();
+		}
 	}
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -3882,7 +3897,22 @@ public Class getServiceClass()
     {
         return ((LiveCodeActivity)getContext()).getServiceClass();
     }
-
+
+	////////////////////////////////////////////////////////////////////////////////
+
+	public int getSystemAppearance()
+	{
+		switch (m_night_mode)
+		{
+			case Configuration.UI_MODE_NIGHT_YES:
+				return 1;
+			case Configuration.UI_MODE_NIGHT_NO:
+			case Configuration.UI_MODE_NIGHT_UNDEFINED:
+			default:
+				return 0;
+		}
+	}
+
     ////////////////////////////////////////////////////////////////////////////////
 
     // url launch callback
@@ -3952,6 +3982,7 @@ public static native void doHeadingChanged(double p_heading, double p_magnetic_h
 	public static native void doShake(int action, long timestamp);
 
 	public static native void doOrientationChanged(int orientation);
+	public static native void doSystemAppearanceChanged();
 
 	public static native void doKeyboardShown(int height);
 	public static native void doKeyboardHidden();

diff --git a/engine/src/lextable.cpp b/engine/src/lextable.cpp
@@ -1690,7 +1690,8 @@ const LT factor_table[] =
         {"syncrate", TT_PROPERTY, P_SYNC_RATE},
         {"syserror", TT_FUNCTION, F_SYS_ERROR},
         {"system", TT_PROPERTY, P_SYSTEM},
-        {"systemcolorselector", TT_PROPERTY, P_SYSTEM_CS},
+		{"systemappearance", TT_PROPERTY, P_SYSTEM_APPEARANCE},
+		{"systemcolorselector", TT_PROPERTY, P_SYSTEM_CS},
         {"systemfileselector", TT_PROPERTY, P_SYSTEM_FS},
 		// IM-2013-12-04: [[ PixelScale ]] The "systemPixelScale" token
 		{"systempixelscale", TT_PROPERTY, P_SYSTEM_PIXEL_SCALE},

diff --git a/engine/src/mac-core.mm b/engine/src/mac-core.mm
@@ -342,12 +342,21 @@ - (void)applicationDidFinishLaunching: (NSNotification *)notification
 
         [t_event release];
     }
+
+	[[NSDistributedNotificationCenter defaultCenter] addObserver:self
+									 selector:@selector(interfaceThemeChangedNotification:)
+								     name:@"AppleInterfaceThemeChangedNotification" object:nil];
 
 	// We started up successfully, so queue the root runloop invocation
 	// message.
 	[self performSelector: @selector(runMainLoop) withObject: nil afterDelay: 0];
 }
 
+- (void)interfaceThemeChangedNotification:(NSNotification *)notification
+{
+	MCPlatformCallbackSendSystemAppearanceChanged();
+}
+
 - (void)runMainLoop
 {
     for(;;)
@@ -608,7 +617,21 @@ void MCPlatformGetSystemProperty(MCPlatformSystemProperty p_property, MCPlatform
         case kMCPlatformSystemPropertyVolume:
             MCMacPlatformGetGlobalVolume(*(double *)r_value);
             break;
-
+
+		case kMCPlatformSystemPropertySystemAppearance:
+		{
+			NSUserDefaults *t_defaults = [NSUserDefaults standardUserDefaults];
+			NSString *t_appearance = [t_defaults stringForKey:@"AppleInterfaceStyle"];
+			if (t_appearance == nil || ![t_appearance isEqualToString:@"Dark"])
+			{
+				*(int16_t *)r_value = kMCPlatformSystemAppearanceLight;
+			}
+			else
+			{
+				*(int16_t *)r_value = kMCPlatformSystemAppearanceDark;
+			}
+		}
+			break;
 		default:
 			assert(false);
 			break;

diff --git a/engine/src/mblandroiddc.cpp b/engine/src/mblandroiddc.cpp
@@ -737,6 +737,16 @@ Window MCScreenDC::get_current_window(void)
 
 ////////////////////////////////////////////////////////////////////////////////
 
+void MCScreenDC::getsystemappearance(MCSystemAppearance &r_appearance)
+{
+	int t_system_appearance;
+	MCAndroidEngineRemoteCall("getSystemAppearance", "i", &t_system_appearance);
+
+	r_appearance = static_cast<MCSystemAppearance>(t_system_appearance);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 static MCRectangle android_view_get_bounds(void)
 {
 	return MCRectangleMake(s_android_bitmap_loc_x, s_android_bitmap_loc_y, s_android_bitmap_width, s_android_bitmap_height);
@@ -2032,6 +2042,7 @@ extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doBackPressed(J
 extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doMenuKey(JNIEnv *env, jobject object) __attribute__((visibility("default")));
 extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doSearchKey(JNIEnv *env, jobject object) __attribute__((visibility("default")));
 extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doOrientationChanged(JNIEnv *env, jobject object, jint orientation) __attribute__((visibility("default")));
+extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doSystemAppearanceChanged(JNIEnv *env, jobject object) __attribute__((visibility("default")));
 extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doTextDone(JNIEnv *env, jobject object) __attribute__((visibility("default")));
 extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doTextCanceled(JNIEnv *env, jobject object) __attribute__((visibility("default")));
 extern "C" JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doMediaDone(JNIEnv *env, jobject object, jstring p_media_content) __attribute__((visibility("default")));
@@ -2375,6 +2386,13 @@ JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doOrientationChanged(JNIEn
 
 //////////
 
+JNIEXPORT void JNICALL Java_com_runrev_android_Engine_doSystemAppearanceChanged(JNIEnv *env, jobject object)
+{
+	MCNotificationPostSystemAppearanceChanged();
+}
+
+//////////
+
 struct MCKeyboardActivatedEvent: public MCCustomEvent
 {
 	MCKeyboardActivatedEvent(float p_height)

diff --git a/engine/src/mbldc.h b/engine/src/mbldc.h
@@ -245,6 +245,8 @@ class MCScreenDC: public MCUIDC
 	Window get_current_window(void);
 
     void refresh_current_window(void);
+
+	void getsystemappearance(MCSystemAppearance &r_appearance);
 private:
 	// The top-left of the mobile 'window' in screen co-ordinates.
 	int32_t m_window_left;

diff --git a/engine/src/mbliphoneapp.mm b/engine/src/mbliphoneapp.mm
@@ -1973,6 +1973,11 @@ - (void)voiceOverStatusChanged
     }
 }
 
+- (void)traitCollectionDidChange:(UITraitCollection *)previousTraitCollection
+{
+	MCNotificationPostSystemAppearanceChanged();
+}
+
 @end
 
 ////////////////////////////////////////////////////////////////////////////////

diff --git a/engine/src/mbliphonedc.mm b/engine/src/mbliphonedc.mm
@@ -857,6 +857,22 @@ static void MCScreenDCDoSnapshot(void *p_env)
 
 ////////////////////////////////////////////////////////////////////////////////
 
+void MCScreenDC::getsystemappearance(MCSystemAppearance &r_appearance)
+{
+	UITraitCollection *t_traits = [MCIPhoneGetRootView() traitCollection];
+	if ([t_traits respondsToSelector: @selector(userInterfaceStyle)] &&
+		[t_traits userInterfaceStyle] == 2 /* UIUserInterfaceStyleDark */)
+	{
+		r_appearance = kMCSystemAppearanceDark;
+	}
+	else
+	{
+		r_appearance = kMCSystemAppearanceLight;
+	}
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 extern void *coretext_font_create_with_name_size_and_style(MCStringRef p_name, uint32_t p_size, bool p_bold, bool p_italic);
 extern bool coretext_font_destroy(void *p_font);
 extern bool coretext_font_get_metrics(void *p_font, float& r_ascent, float& r_descent, float& r_leading, float& r_xheight);

diff --git a/engine/src/mblnotification.cpp b/engine/src/mblnotification.cpp
@@ -180,4 +180,9 @@ void MCNotificationPostLaunchDataChanged()
 	/* UNCHECKED */ MCNotificationPostCustom(MCM_launch_data_changed, 0);
 }
 
+void MCNotificationPostSystemAppearanceChanged()
+{
+	/* UNCHECKED */ MCNotificationPostCustom(MCM_system_appearance_changed, 0);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
-Original file line number
+Diff line change
@@ Expand Up / @@ -1973,6 +1973,11 @@ - (void)voiceOverStatusChanged @@
         }
     }
+    - (void)traitCollectionDidChange:(UITraitCollection *)previousTraitCollection
+    {
+    	MCNotificationPostSystemAppearanceChanged();
+    }
     @end
     ////////////////////////////////////////////////////////////////////////////////
@@ Expand Down @@