Add portable accessibility semantics

CodenameOne/src/com/codename1/impl/CodenameOneImplementation.java

@@ -91,6 +91,8 @@
 import com.codename1.ui.TextArea;
 import com.codename1.ui.TextSelection;
 import com.codename1.ui.Transform;
+import com.codename1.ui.accessibility.AccessibilityManager;
+import com.codename1.ui.accessibility.AccessibilityTreeSnapshot;
 import com.codename1.ui.animations.Animation;
 import com.codename1.ui.animations.Transition;
 import com.codename1.ui.events.ActionEvent;
@@ -11132,6 +11134,35 @@ public void announceForAccessibility(Component cmp, String text) {
         // should override this method.
     }
 
+    /// Called after the portable semantic tree changes. Platform ports should
+    /// invalidate their native virtual accessibility roots and request the latest
+    /// immutable snapshot with {@link #getAccessibilityTreeSnapshot()}.
+    public void accessibilityTreeChanged(int changeType) {
+    }
+
+    /// Returns the latest immutable semantic tree for the current form.
+    public AccessibilityTreeSnapshot getAccessibilityTreeSnapshot() {
+        return AccessibilityManager.getInstance().getCurrentSnapshot();
+    }
+
+    /// Dispatches an action from a native virtual accessibility node onto the EDT.
+    public boolean performAccessibilityAction(long nodeId, String actionId, Object argument) {
+        return AccessibilityManager.getInstance().performAction(nodeId, actionId, argument);
+    }
+
+    /// Returns true when this port exposes the portable virtual semantic tree.
+    public boolean isAccessibilityTreeSupported() {
+        return false;
+    }
+
+    /// Returns true when semantic invalidations should be projected eagerly.
+    /// Pull-based ports should override this to return true only while assistive
+    /// technology is active. Ports whose semantic projection must always remain
+    /// attached, such as web ARIA, may return true unconditionally.
+    public boolean isAccessibilityTreeUpdateRequired() {
+        return isAccessibilityTreeSupported();
+    }
+
     /// Returns true if the user has selected larger type fonts in the system settings.
     /// Default implementation returns false.
     ///
@@ -11154,6 +11185,56 @@ public float getLargerTextScale() {
         return 1.0f;
     }
 
+    /// Returns true when the user requests stronger foreground/background contrast.
+    public boolean isHighContrastEnabled() {
+        return false;
+    }
+
+    /// Returns true when the user requests that information isn't conveyed by color alone.
+    public boolean isDifferentiateWithoutColorEnabled() {
+        return false;
+    }
+
+    /// Returns the selected color-vision correction mode.
+    public com.codename1.ui.AccessibilityColorVisionDeficiency getColorVisionDeficiency() {
+        return com.codename1.ui.AccessibilityColorVisionDeficiency.UNKNOWN;
+    }
+
+    /// Returns true when the user requests reduced or disabled nonessential motion.
+    public boolean isReduceMotionEnabled() {
+        return false;
+    }
+
+    /// Returns true when the user requests reduced transparency and blur effects.
+    public boolean isReduceTransparencyEnabled() {
+        return false;
+    }
+
+    /// Returns true when the user requests heavier text weight.
+    public boolean isBoldTextEnabled() {
+        return false;
+    }
+
+    /// Returns true when the operating system is inverting displayed colors.
+    public boolean isInvertColorsEnabled() {
+        return false;
+    }
+
+    /// Returns true when the operating system requests a grayscale presentation.
+    public boolean isGrayscaleEnabled() {
+        return false;
+    }
+
+    /// Returns true when switches should include visible on/off labels.
+    public boolean isOnOffSwitchLabelsEnabled() {
+        return false;
+    }
+
+    /// Returns true when a screen reader or touch-exploration service is active.
+    public boolean isScreenReaderEnabled() {
+        return false;
+    }
+
     /// Returns the stack trace from the exception on the given
     /// thread. This API isn't supported on all platforms and may
     /// return a blank string when unavailable.

CodenameOne/src/com/codename1/ui/AccessibilityColorVisionDeficiency.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2026, Codename One and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Codename One designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Codename One through http://www.codenameone.com/ if you
+ * need additional information or have any questions.
+ */
+package com.codename1.ui;
+
+/// Describes a color-vision deficiency selected in the operating system or
+/// simulated by the Java SE simulator.
+///
+/// Applications should never infer that color alone is safe when this value is
+/// {@link #NONE} or {@link #UNKNOWN}. Use text, shape, iconography, or patterns
+/// in addition to color for every important distinction.
+public enum AccessibilityColorVisionDeficiency {
+    /// The platform reports that no color-vision correction is enabled.
+    NONE,
+    /// Reduced sensitivity to red light.
+    PROTANOPIA,
+    /// Reduced sensitivity to green light.
+    DEUTERANOPIA,
+    /// Reduced sensitivity to blue light.
+    TRITANOPIA,
+    /// Colors are presented as shades of gray.
+    MONOCHROMACY,
+    /// The platform doesn't expose the selected correction mode.
+    UNKNOWN
+}

CodenameOne/src/com/codename1/ui/Button.java

@@ -24,6 +24,7 @@
 
 package com.codename1.ui;
 
+import com.codename1.ui.accessibility.AccessibilityManager;
 import com.codename1.ui.events.ActionEvent;
 import com.codename1.ui.events.ActionListener;
 import com.codename1.ui.events.ActionSource;
@@ -992,7 +993,11 @@ public boolean isToggle() {
     ///
     /// - `toggle`: the toggle to set
     public void setToggle(boolean toggle) {
+        if (this.toggle == toggle) {
+            return;
+        }
         this.toggle = toggle;
+        accessibilityChanged(AccessibilityManager.CHANGE_STRUCTURE | AccessibilityManager.CHANGE_STATE);
         if (toggle && "CheckBox".equals(getUIID()) || "RadioButton".equals(getUIID())) {
             setUIID("ToggleButton");
         }

CodenameOne/src/com/codename1/ui/CN.java

@@ -1072,6 +1072,56 @@ public static Boolean isDarkMode() {
         return Display.INSTANCE.isDarkMode();
     }
 
+    /// Returns true when the user requests stronger foreground/background contrast.
+    public static boolean isHighContrastEnabled() {
+        return Display.INSTANCE.isHighContrastEnabled();
+    }
+
+    /// Returns true when the user requests that information isn't conveyed by color alone.
+    public static boolean isDifferentiateWithoutColorEnabled() {
+        return Display.INSTANCE.isDifferentiateWithoutColorEnabled();
+    }
+
+    /// Returns the selected color-vision correction mode.
+    public static AccessibilityColorVisionDeficiency getColorVisionDeficiency() {
+        return Display.INSTANCE.getColorVisionDeficiency();
+    }
+
+    /// Returns true when the user requests reduced or disabled nonessential motion.
+    public static boolean isReduceMotionEnabled() {
+        return Display.INSTANCE.isReduceMotionEnabled();
+    }
+
+    /// Returns true when the user requests reduced transparency and blur effects.
+    public static boolean isReduceTransparencyEnabled() {
+        return Display.INSTANCE.isReduceTransparencyEnabled();
+    }
+
+    /// Returns true when the user requests heavier text weight.
+    public static boolean isBoldTextEnabled() {
+        return Display.INSTANCE.isBoldTextEnabled();
+    }
+
+    /// Returns true when the operating system is inverting displayed colors.
+    public static boolean isInvertColorsEnabled() {
+        return Display.INSTANCE.isInvertColorsEnabled();
+    }
+
+    /// Returns true when the operating system requests a grayscale presentation.
+    public static boolean isGrayscaleEnabled() {
+        return Display.INSTANCE.isGrayscaleEnabled();
+    }
+
+    /// Returns true when switches should include visible on/off labels.
+    public static boolean isOnOffSwitchLabelsEnabled() {
+        return Display.INSTANCE.isOnOffSwitchLabelsEnabled();
+    }
+
+    /// Returns true when a screen reader or touch-exploration service is active.
+    public static boolean isScreenReaderEnabled() {
+        return Display.INSTANCE.isScreenReaderEnabled();
+    }
+
     /// Override the default dark mode setting
     ///
     /// #### Parameters

CodenameOne/src/com/codename1/ui/CheckBox.java

@@ -24,6 +24,7 @@
 
 package com.codename1.ui;
 
+import com.codename1.ui.accessibility.AccessibilityManager;
 import com.codename1.cloud.BindTarget;
 import com.codename1.ui.events.ActionEvent;
 import com.codename1.ui.events.ActionListener;
@@ -173,6 +174,7 @@ public void setSelected(boolean selected) {
         this.selected = selected;
         if (changed) {
             fireChangeEvent();
+            accessibilityChanged(AccessibilityManager.CHANGE_STATE);
         }
         repaint();
     }