Accessibility for Android

This enables both modes for TalkBack,
explore-by-touch and the normal swiping mode.

It is partially inspired by the BarGraphView example
of the Google/Android Eyes-Free project.

Note that for any accessibility to work you'll need
a device with api level 16 at least.
Using reflection we should be able to dynamically pick up
the classes if we have the high enough api level.

Change-Id: I11b93bead451483782a1711434d45c8f9a35996f
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>

7 files changed, 429 insertions, 0 deletions

diff --git a/src/android/accessibility/jar/AndroidManifest.xml b/src/android/accessibility/jar/AndroidManifest.xml
new file mode 100644
index 0000000000..dc8343a55a
--- /dev/null
+++ b/src/android/accessibility/jar/AndroidManifest.xml
@@ -0,0 +1,7 @@
+<?xml version='1.0' encoding='utf-8'?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    android:versionCode="1"
+    android:versionName="1.0"
+    package="org.qtproject.qt5.android.accessibility">
+    <supports-screens android:largeScreens="true" android:normalScreens="true" android:anyDensity="true" android:smallScreens="true"/>
+</manifest>
diff --git a/src/android/accessibility/jar/bundledjar.pro b/src/android/accessibility/jar/bundledjar.pro
new file mode 100644
index 0000000000..85ba810310
--- /dev/null
+++ b/src/android/accessibility/jar/bundledjar.pro
@@ -0,0 +1,3 @@
+TARGET = QtAndroidAccessibility-bundled
+CONFIG += bundled_jar_file
+include(jar.pri)
diff --git a/src/android/accessibility/jar/distributedjar.pro b/src/android/accessibility/jar/distributedjar.pro
new file mode 100644
index 0000000000..d161cf0cf6
--- /dev/null
+++ b/src/android/accessibility/jar/distributedjar.pro
@@ -0,0 +1,2 @@
+TARGET = QtAndroidAccessibility
+include(jar.pri)
diff --git a/src/android/accessibility/jar/jar.pri b/src/android/accessibility/jar/jar.pri
new file mode 100644
index 0000000000..23b3ff7087
--- /dev/null
+++ b/src/android/accessibility/jar/jar.pri
@@ -0,0 +1,14 @@
+CONFIG += java
+DESTDIR = $$[QT_INSTALL_PREFIX/get]/jar
+API_VERSION = android-16
+
+PATHPREFIX = $$PWD/src/org/qtproject/qt5/android/accessibility
+
+JAVACLASSPATH += $$PWD/src/
+JAVASOURCES += \
+    $$PATHPREFIX/QtAccessibilityDelegate.java \
+    $$PATHPREFIX/QtNativeAccessibility.java
+
+# install
+target.path = $$[QT_INSTALL_PREFIX]/jar
+INSTALLS += target
\ No newline at end of file
diff --git a/src/android/accessibility/jar/jar.pro b/src/android/accessibility/jar/jar.pro
new file mode 100644
index 0000000000..8d19c1b7d6
--- /dev/null
+++ b/src/android/accessibility/jar/jar.pro
@@ -0,0 +1,2 @@
+TEMPLATE = subdirs
+SUBDIRS += bundledjar.pro distributedjar.pro
diff --git a/src/android/accessibility/jar/src/org/qtproject/qt5/android/accessibility/QtAccessibilityDelegate.java b/src/android/accessibility/jar/src/org/qtproject/qt5/android/accessibility/QtAccessibilityDelegate.java
new file mode 100644
index 0000000000..669fbaab0d
--- /dev/null
+++ b/src/android/accessibility/jar/src/org/qtproject/qt5/android/accessibility/QtAccessibilityDelegate.java
@@ -0,0 +1,343 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Android port of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+
+package org.qtproject.qt5.android.accessibility;
+
+import android.accessibilityservice.AccessibilityService;
+import android.graphics.Rect;
+import android.os.Bundle;
+import android.util.Log;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewParent;
+import android.text.TextUtils;
+
+import android.view.accessibility.*;
+import android.view.MotionEvent;
+
+import android.content.Context;
+
+import java.util.LinkedList;
+import java.util.List;
+
+public class QtAccessibilityDelegate extends View.AccessibilityDelegate
+{
+    private static final String TAG = "Qt A11Y";
+
+    // Qt uses the upper half of the unsiged integers
+    // all low positive ints should be fine.
+    public static final int INVALID_ID = 333; // half evil
+
+    // The platform might ask for the class implementing the "view".
+    // Pretend to be an inner class of the QtSurface.
+    private static final String DEFAULT_CLASS_NAME = "$VirtualChild";
+
+    private final View m_view;
+    private final AccessibilityManager m_manager;
+
+    // The accessible object that currently has the "accessibility focus"
+    // usually indicated by a yellow rectangle on screen.
+    private int m_focusedVirtualViewId = INVALID_ID;
+    // When exploring the screen by touch, the item "hovered" by the finger.
+    private int m_hoveredVirtualViewId = INVALID_ID;
+
+    // Cache coordinates of the view to know the global offset
+    // this is because the Android platform window does not take
+    // the offset of the view on screen into account (eg status bar on top)
+    private final int[] m_globalOffset = new int[2];
+
+    public QtAccessibilityDelegate(View host)
+    {
+        m_view = host;
+        m_manager = (AccessibilityManager) host.getContext()
+                .getSystemService(Context.ACCESSIBILITY_SERVICE);
+
+        // Enable Qt Accessibility so that notifications are enabled
+        QtNativeAccessibility.setActive(true);
+    }
+
+    @Override
+    public AccessibilityNodeProvider getAccessibilityNodeProvider(View host)
+    {
+        return m_nodeProvider;
+    }
+
+    // For "explore by touch" we need all movement events here first
+    // (user moves finger over screen to discover items on screen).
+    public boolean dispatchHoverEvent(MotionEvent event)
+    {
+        if (!m_manager.isTouchExplorationEnabled()) {
+            return false;
+        }
+
+        int virtualViewId = QtNativeAccessibility.hitTest(event.getX(), event.getY());
+        if (virtualViewId == INVALID_ID) {
+            virtualViewId = View.NO_ID;
+        }
+
+        switch (event.getAction()) {
+            case MotionEvent.ACTION_HOVER_ENTER:
+            case MotionEvent.ACTION_HOVER_MOVE:
+                setHoveredVirtualViewId(virtualViewId);
+                break;
+            case MotionEvent.ACTION_HOVER_EXIT:
+                setHoveredVirtualViewId(virtualViewId);
+                break;
+        }
+
+        return true;
+    }
+
+    public boolean sendEventForVirtualViewId(int virtualViewId, int eventType)
+    {
+        if ((virtualViewId == INVALID_ID) || !m_manager.isEnabled()) {
+            Log.w(TAG, "sendEventForVirtualViewId for invalid view");
+            return false;
+        }
+
+        final ViewGroup group = (ViewGroup) m_view.getParent();
+        if (group == null) {
+            Log.w(TAG, "Could not send AccessibilityEvent because group was null. This should really not happen.");
+            return false;
+        }
+
+        final AccessibilityEvent event;
+        event = getEventForVirtualViewId(virtualViewId, eventType);
+        return group.requestSendAccessibilityEvent(m_view, event);
+    }
+
+    public void invalidateVirtualViewId(int virtualViewId)
+    {
+        sendEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_WINDOW_CONTENT_CHANGED);
+    }
+
+    private void setHoveredVirtualViewId(int virtualViewId)
+    {
+        if (m_hoveredVirtualViewId == virtualViewId) {
+            return;
+        }
+
+        final int previousVirtualViewId = m_hoveredVirtualViewId;
+        m_hoveredVirtualViewId = virtualViewId;
+        sendEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_VIEW_HOVER_ENTER);
+        sendEventForVirtualViewId(previousVirtualViewId, AccessibilityEvent.TYPE_VIEW_HOVER_EXIT);
+    }
+
+    private AccessibilityEvent getEventForVirtualViewId(int virtualViewId, int eventType)
+    {
+        final AccessibilityEvent event = AccessibilityEvent.obtain(eventType);
+
+        event.setEnabled(true);
+        event.setClassName(m_view.getClass().getName() + DEFAULT_CLASS_NAME);
+
+        event.setContentDescription(QtNativeAccessibility.descriptionForAccessibleObject(virtualViewId));
+        if (event.getText().isEmpty() && TextUtils.isEmpty(event.getContentDescription()))
+            Log.w(TAG, "AccessibilityEvent with empty description");
+
+        event.setPackageName(m_view.getContext().getPackageName());
+        event.setSource(m_view, virtualViewId);
+        return event;
+    }
+
+    private void dumpNodes(int parentId)
+    {
+        Log.i(TAG, "A11Y hierarchy: " + parentId + " parent: " + QtNativeAccessibility.parentId(parentId));
+        Log.i(TAG, "    desc: " + QtNativeAccessibility.descriptionForAccessibleObject(parentId) + " rect: " + QtNativeAccessibility.screenRect(parentId));
+        Log.i(TAG, " NODE: " + getNodeForVirtualViewId(parentId));
+        int[] ids = QtNativeAccessibility.childIdListForAccessibleObject(parentId);
+        for (int i = 0; i < ids.length; ++i) {
+            Log.i(TAG, parentId + " has child: " + ids[i]);
+            dumpNodes(ids[i]);
+        }
+    }
+
+    private AccessibilityNodeInfo getNodeForView()
+    {
+        // Since we don't want the parent to be focusable, but we can't remove
+        // actions from a node, copy over the necessary fields.
+        final AccessibilityNodeInfo result = AccessibilityNodeInfo.obtain(m_view);
+        final AccessibilityNodeInfo source = AccessibilityNodeInfo.obtain(m_view);
+        m_view.onInitializeAccessibilityNodeInfo(source);
+
+        // Get the actual position on screen, taking the status bar into account.
+        m_view.getLocationOnScreen(m_globalOffset);
+        final int offsetX = m_globalOffset[0];
+        final int offsetY = m_globalOffset[1];
+
+        // Copy over parent and screen bounds.
+        final Rect m_tempParentRect = new Rect();
+        source.getBoundsInParent(m_tempParentRect);
+        result.setBoundsInParent(m_tempParentRect);
+
+        final Rect m_tempScreenRect = new Rect();
+        source.getBoundsInScreen(m_tempScreenRect);
+        m_tempScreenRect.offset(offsetX, offsetY);
+        result.setBoundsInScreen(m_tempScreenRect);
+
+        // Set up the parent view, if applicable.
+        final ViewParent parent = m_view.getParent();
+        if (parent instanceof View) {
+            result.setParent((View) parent);
+        }
+
+        result.setVisibleToUser(source.isVisibleToUser());
+        result.setPackageName(source.getPackageName());
+        result.setClassName(source.getClassName());
+
+// Spit out the entire hierarchy for debugging purposes
+//        dumpNodes(-1);
+
+        int[] ids = QtNativeAccessibility.childIdListForAccessibleObject(-1);
+        for (int i = 0; i < ids.length; ++i)
+            result.addChild(m_view, ids[i]);
+
+        return result;
+    }
+
+    private AccessibilityNodeInfo getNodeForVirtualViewId(int virtualViewId)
+    {
+        final AccessibilityNodeInfo node = AccessibilityNodeInfo.obtain();
+
+        node.setClassName(m_view.getClass().getName() + DEFAULT_CLASS_NAME);
+        node.setPackageName(m_view.getContext().getPackageName());
+
+        node.setSource(m_view, virtualViewId);
+        QtNativeAccessibility.populateNode(virtualViewId, node);
+        if (TextUtils.isEmpty(node.getText()) && TextUtils.isEmpty(node.getContentDescription()))
+            Log.w(TAG, "AccessibilityNodeInfo with empty contentDescription: " + virtualViewId);
+
+        int parentId = QtNativeAccessibility.parentId(virtualViewId);
+        node.setParent(m_view, parentId);
+
+        Rect screenRect = QtNativeAccessibility.screenRect(virtualViewId);
+        final int offsetX = m_globalOffset[0];
+        final int offsetY = m_globalOffset[1];
+        screenRect.offset(offsetX, offsetY);
+        node.setBoundsInScreen(screenRect);
+
+        Rect rectInParent = screenRect;
+        Rect parentScreenRect = QtNativeAccessibility.screenRect(parentId);
+        rectInParent.offset(-parentScreenRect.left, -parentScreenRect.top);
+        node.setBoundsInParent(rectInParent);
+
+        // Manage internal accessibility focus state.
+        if (m_focusedVirtualViewId == virtualViewId) {
+            node.setAccessibilityFocused(true);
+            node.addAction(AccessibilityNodeInfo.ACTION_CLEAR_ACCESSIBILITY_FOCUS);
+        } else {
+            node.setAccessibilityFocused(false);
+            node.addAction(AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS);
+        }
+
+        int[] ids = QtNativeAccessibility.childIdListForAccessibleObject(virtualViewId);
+        for (int i = 0; i < ids.length; ++i)
+            node.addChild(m_view, ids[i]);
+        return node;
+    }
+
+    private AccessibilityNodeProvider m_nodeProvider = new AccessibilityNodeProvider()
+    {
+        @Override
+        public AccessibilityNodeInfo createAccessibilityNodeInfo(int virtualViewId)
+        {
+            if (virtualViewId == View.NO_ID) {
+                return getNodeForView();
+            }
+            return getNodeForVirtualViewId(virtualViewId);
+        }
+
+        @Override
+        public boolean performAction(int virtualViewId, int action, Bundle arguments)
+        {
+            boolean handled = false;
+            //Log.i(TAG, "PERFORM ACTION: " + action + " on " + virtualViewId);
+            switch (action) {
+                case AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS:
+                    // Only handle the FOCUS action if it's placing focus on
+                    // a different view that was previously focused.
+                    if (m_focusedVirtualViewId != virtualViewId) {
+                        m_focusedVirtualViewId = virtualViewId;
+                        m_view.invalidate();
+                        sendEventForVirtualViewId(virtualViewId,
+                                AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED);
+                        handled = true;
+                    }
+                    break;
+                case AccessibilityNodeInfo.ACTION_CLEAR_ACCESSIBILITY_FOCUS:
+                    if (m_focusedVirtualViewId == virtualViewId) {
+                        m_focusedVirtualViewId = INVALID_ID;
+                    }
+                    // Since we're managing focus at the parent level, we are
+                    // likely to receive a FOCUS action before a CLEAR_FOCUS
+                    // action. We'll give the benefit of the doubt to the
+                    // framework and always handle FOCUS_CLEARED.
+                    m_view.invalidate();
+                    sendEventForVirtualViewId(virtualViewId,
+                            AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED);
+                    handled = true;
+                    break;
+                default:
+                    // Let the node provider handle focus for the view node.
+                    if (virtualViewId == View.NO_ID) {
+                        return m_view.performAccessibilityAction(action, arguments);
+                    }
+            }
+            handled |= performActionForVirtualViewId(virtualViewId, action, arguments);
+
+            return handled;
+        }
+    };
+
+    protected boolean performActionForVirtualViewId(int virtualViewId, int action, Bundle arguments)
+    {
+//        Log.i(TAG, "ACTION " + action + " on " + virtualViewId);
+//        dumpNodes(virtualViewId);
+        switch (action) {
+        case AccessibilityNodeInfo.ACTION_CLICK:
+            boolean success = QtNativeAccessibility.clickAction(virtualViewId);
+            if (success)
+                sendEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_VIEW_CLICKED);
+            return success;
+        }
+        return false;
+    }
+}
diff --git a/src/android/accessibility/jar/src/org/qtproject/qt5/android/accessibility/QtNativeAccessibility.java b/src/android/accessibility/jar/src/org/qtproject/qt5/android/accessibility/QtNativeAccessibility.java
new file mode 100644
index 0000000000..b1cc82c065
--- /dev/null
+++ b/src/android/accessibility/jar/src/org/qtproject/qt5/android/accessibility/QtNativeAccessibility.java
@@ -0,0 +1,58 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the Android port of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+package org.qtproject.qt5.android.accessibility;
+
+import android.graphics.Rect;
+import android.view.accessibility.AccessibilityNodeInfo;
+
+class QtNativeAccessibility
+{
+    static native void setActive(boolean enable);
+    static native int[] childIdListForAccessibleObject(int objectId);
+    static native int parentId(int objectId);
+    static native String descriptionForAccessibleObject(int objectId);
+    static native Rect screenRect(int objectId);
+    static native int hitTest(float x, float y);
+    static native boolean clickAction(int objectId);
+
+    static native void populateNode(int objectId, AccessibilityNodeInfo node);
+}