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Diffstat (limited to 'src/android/jar/src/org/qtproject/qt/android/QtAccessibilityDelegate.java')
| -rw-r--r-- | src/android/jar/src/org/qtproject/qt/android/QtAccessibilityDelegate.java | 523 |
1 files changed, 523 insertions, 0 deletions
diff --git a/src/android/jar/src/org/qtproject/qt/android/QtAccessibilityDelegate.java b/src/android/jar/src/org/qtproject/qt/android/QtAccessibilityDelegate.java new file mode 100644 index 0000000000..d23c87e792 --- /dev/null +++ b/src/android/jar/src/org/qtproject/qt/android/QtAccessibilityDelegate.java @@ -0,0 +1,523 @@ +// Copyright (C) 2016 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only + + +package org.qtproject.qt.android; + +import android.app.Activity; +import android.content.Context; +import android.graphics.Rect; +import android.os.Build; +import android.os.Bundle; +import android.system.Os; +import android.text.TextUtils; +import android.util.Log; +import android.view.MotionEvent; +import android.view.View; +import android.view.ViewGroup; +import android.view.ViewParent; +import android.view.accessibility.AccessibilityEvent; +import android.view.accessibility.AccessibilityManager; +import android.view.accessibility.AccessibilityNodeInfo; +import android.view.accessibility.AccessibilityNodeInfo.CollectionInfo; +import android.view.accessibility.AccessibilityNodeProvider; + +class QtAccessibilityDelegate extends View.AccessibilityDelegate +{ + private static final String TAG = "Qt A11Y"; + + // Qt uses the upper half of the unsigned 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 View m_view = null; + private final AccessibilityManager m_manager; + private final QtLayout m_layout; + + // 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]; + private int m_oldOffsetX = 0; + private int m_oldOffsetY = 0; + + private class HoverEventListener implements View.OnHoverListener + { + @Override + public boolean onHover(View v, MotionEvent event) + { + return dispatchHoverEvent(event); + } + } + // TODO do we want to have one QtAccessibilityDelegate for the whole app (QtRootLayout) or + // e.g. one per window? + public QtAccessibilityDelegate(QtLayout layout) + { + m_layout = layout; + + m_manager = (AccessibilityManager) m_layout.getContext().getSystemService(Context.ACCESSIBILITY_SERVICE); + if (m_manager != null) { + AccessibilityManagerListener accServiceListener = new AccessibilityManagerListener(); + if (!m_manager.addAccessibilityStateChangeListener(accServiceListener)) + Log.w("Qt A11y", "Could not register a11y state change listener"); + if (m_manager.isEnabled()) + accServiceListener.onAccessibilityStateChanged(true); + } + } + + private class AccessibilityManagerListener implements AccessibilityManager.AccessibilityStateChangeListener + { + @Override + public void onAccessibilityStateChanged(boolean enabled) + { + if (Os.getenv("QT_ANDROID_DISABLE_ACCESSIBILITY") != null) + return; + if (enabled) { + try { + View view = m_view; + if (view == null) { + view = new View(m_layout.getContext()); + view.setId(View.NO_ID); + } + + // ### Keep this for debugging for a while. It allows us to visually see that our View + // ### is on top of the surface(s) + //noinspection CommentedOutCode + { + // ColorDrawable color = new ColorDrawable(0x80ff8080); //0xAARRGGBB + // view.setBackground(color); + } + view.setAccessibilityDelegate(QtAccessibilityDelegate.this); + + // if all is fine, add it to the layout + if (m_view == null) { + //m_layout.addAccessibilityView(view); + m_layout.addView(view, m_layout.getChildCount(), + new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT)); + } + m_view = view; + + m_view.setOnHoverListener(new HoverEventListener()); + } catch (Exception e) { + // Unknown exception means something went wrong. + Log.w("Qt A11y", "Unknown exception: " + e); + } + } else { + if (m_view != null) { + m_layout.removeView(m_view); + m_view = null; + } + } + + QtNativeAccessibility.setActive(enabled); + } + } + + + @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). + private 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: + case MotionEvent.ACTION_HOVER_EXIT: + setHoveredVirtualViewId(virtualViewId); + break; + } + + return true; + } + + public void notifyScrolledEvent(int viewId) + { + QtNative.runAction(() -> sendEventForVirtualViewId(viewId, + AccessibilityEvent.TYPE_VIEW_SCROLLED)); + } + + public void notifyLocationChange(int viewId) + { + QtNative.runAction(() -> { + if (m_focusedVirtualViewId == viewId) + invalidateVirtualViewId(m_focusedVirtualViewId); + }); + } + + public void notifyObjectHide(int viewId, int parentId) + { + QtNative.runAction(() -> { + // If the object had accessibility focus, we need to clear it. + // Note: This code is mostly copied from + // AccessibilityNodeProvider::performAction, but we remove the + // focus only if the focused view id matches the one that was hidden. + if (m_focusedVirtualViewId == viewId) { + m_focusedVirtualViewId = INVALID_ID; + m_view.invalidate(); + sendEventForVirtualViewId(viewId, + AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED); + } + // When the object is hidden, we need to notify its parent about + // content change, not the hidden object itself + invalidateVirtualViewId(parentId); + }); + } + + public void notifyObjectShow(int parentId) + { + QtNative.runAction(() -> { + // When the object is shown, we need to notify its parent about + // content change, not the shown object itself + invalidateVirtualViewId(parentId); + }); + } + + public void notifyObjectFocus(int viewId) + { + QtNative.runAction(() -> { + if (m_view == null) + return; + m_focusedVirtualViewId = viewId; + m_view.invalidate(); + sendEventForVirtualViewId(viewId, + AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED); + }); + } + + public void notifyValueChanged(int viewId, String value) + { + QtNative.runAction(() -> { + // Send a TYPE_ANNOUNCEMENT event with the new value + + if ((viewId == INVALID_ID) || !m_manager.isEnabled()) { + Log.w(TAG, "notifyValueChanged() for invalid view"); + return; + } + + final ViewGroup group = (ViewGroup) m_view.getParent(); + if (group == null) { + Log.w(TAG, "Could not announce value because ViewGroup was null."); + return; + } + + final AccessibilityEvent event = + AccessibilityEvent.obtain(AccessibilityEvent.TYPE_ANNOUNCEMENT); + + event.setEnabled(true); + event.setClassName(m_view.getClass().getName() + DEFAULT_CLASS_NAME); + + event.setContentDescription(value); + + if (event.getText().isEmpty() && TextUtils.isEmpty(event.getContentDescription())) { + Log.w(TAG, "No value to announce for " + event.getClassName()); + return; + } + + event.setPackageName(m_view.getContext().getPackageName()); + event.setSource(m_view, viewId); + + if (!group.requestSendAccessibilityEvent(m_view, event)) + Log.w(TAG, "Failed to send value change announcement for " + event.getClassName()); + }); + } + + public void sendEventForVirtualViewId(int virtualViewId, int eventType) + { + final AccessibilityEvent event = getEventForVirtualViewId(virtualViewId, eventType); + sendAccessibilityEvent(event); + } + + public void sendAccessibilityEvent(AccessibilityEvent event) + { + if (event == null) + return; + + 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; + } + + group.requestSendAccessibilityEvent(m_view, event); + } + + public void invalidateVirtualViewId(int virtualViewId) + { + final AccessibilityEvent event = getEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_WINDOW_CONTENT_CHANGED); + + if (event == null) + return; + + event.setContentChangeTypes(AccessibilityEvent.CONTENT_CHANGE_TYPE_SUBTREE); + sendAccessibilityEvent(event); + } + + 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) + { + if ((virtualViewId == INVALID_ID) || !m_manager.isEnabled()) { + Log.w(TAG, "getEventForVirtualViewId for invalid view"); + return null; + } + + if (m_layout.getChildCount() == 0) + return null; + + 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; + } + + // This can be used for debug by performActionForVirtualViewId() + /** @noinspection unused*/ + 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 id : ids) { + Log.i(TAG, parentId + " has child: " + id); + dumpNodes(id); + } + } + + 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); + + if (m_layout.getChildCount() != 0) { + int[] ids = QtNativeAccessibility.childIdListForAccessibleObject(-1); + for (int id : ids) + result.addChild(m_view, id); + } + + // The offset values have changed, so we need to re-focus the + // currently focused item, otherwise it will have an incorrect + // focus frame + if ((m_oldOffsetX != offsetX) || (m_oldOffsetY != offsetY)) { + m_oldOffsetX = offsetX; + m_oldOffsetY = offsetY; + if (m_focusedVirtualViewId != INVALID_ID) { + m_nodeProvider.performAction(m_focusedVirtualViewId, + AccessibilityNodeInfo.ACTION_CLEAR_ACCESSIBILITY_FOCUS, + new Bundle()); + m_nodeProvider.performAction(m_focusedVirtualViewId, + AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS, + new Bundle()); + } + } + + 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()); + + if (m_layout.getChildCount() == 0 || !QtNativeAccessibility.populateNode(virtualViewId, node)) { + return node; + } + + // set only if valid, otherwise we return a node that is invalid and will crash when accessed + node.setSource(m_view, virtualViewId); + + 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 parentScreenRect = QtNativeAccessibility.screenRect(parentId); + screenRect.offset(-parentScreenRect.left, -parentScreenRect.top); + node.setBoundsInParent(screenRect); + + // Manage internal accessibility focus state. + if (m_focusedVirtualViewId == virtualViewId) { + node.setAccessibilityFocused(true); + node.addAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_CLEAR_ACCESSIBILITY_FOCUS); + } else { + node.setAccessibilityFocused(false); + node.addAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_ACCESSIBILITY_FOCUS); + } + + int[] ids = QtNativeAccessibility.childIdListForAccessibleObject(virtualViewId); + for (int id : ids) + node.addChild(m_view, id); + if (node.isScrollable()) { + if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) { + node.setCollectionInfo(new CollectionInfo(ids.length, 1, false)); + } else { + node.setCollectionInfo(CollectionInfo.obtain(ids.length, 1, false)); + } + } + + return node; + } + + private final AccessibilityNodeProvider m_nodeProvider = new AccessibilityNodeProvider() + { + @Override + public AccessibilityNodeInfo createAccessibilityNodeInfo(int virtualViewId) + { + if (virtualViewId == View.NO_ID || m_layout.getChildCount() == 0) { + 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); + + return handled; + } + }; + + protected boolean performActionForVirtualViewId(int virtualViewId, int action) + { + //noinspection CommentedOutCode + { + // Log.i(TAG, "ACTION " + action + " on " + virtualViewId); + // dumpNodes(virtualViewId); + } + boolean success = false; + switch (action) { + case AccessibilityNodeInfo.ACTION_CLICK: + success = QtNativeAccessibility.clickAction(virtualViewId); + if (success) + sendEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_VIEW_CLICKED); + break; + case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: + success = QtNativeAccessibility.scrollForward(virtualViewId); + if (success) + sendEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_VIEW_SCROLLED); + break; + case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: + success = QtNativeAccessibility.scrollBackward(virtualViewId); + if (success) + sendEventForVirtualViewId(virtualViewId, AccessibilityEvent.TYPE_VIEW_SCROLLED); + break; + } + return success; + } +} |