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yaakovschectmanyaakovschectman
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Announce alerts through SemanticsService on Windows (flutter#37173)
* Corresponds to changes by reverted PR flutter/engine#36966. * Changes on top of original reverted PR that add IServiceProvider and COM_INTERFACE_ENTRY's to the new node classes. * self_com_ unused
1 parent 224b401 commit 74f0219

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+1008
-3
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‎ci/licenses_golden/licenses_flutter‎

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@@ -3073,9 +3073,13 @@ FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_texture_regi
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FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_value.h
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FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/fl_view.h
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FILE: ../../../flutter/shell/platform/linux/public/flutter_linux/flutter_linux.h
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FILE: ../../../flutter/shell/platform/windows/accessibility_alert.cc
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FILE: ../../../flutter/shell/platform/windows/accessibility_alert.h
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FILE: ../../../flutter/shell/platform/windows/accessibility_bridge_delegate_windows.cc
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FILE: ../../../flutter/shell/platform/windows/accessibility_bridge_delegate_windows.h
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FILE: ../../../flutter/shell/platform/windows/accessibility_bridge_delegate_windows_unittests.cc
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FILE: ../../../flutter/shell/platform/windows/accessibility_root_node.cc
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FILE: ../../../flutter/shell/platform/windows/accessibility_root_node.h
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FILE: ../../../flutter/shell/platform/windows/angle_surface_manager.cc
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FILE: ../../../flutter/shell/platform/windows/angle_surface_manager.h
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FILE: ../../../flutter/shell/platform/windows/client_wrapper/dart_project_unittests.cc

‎shell/platform/windows/BUILD.gn‎

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@@ -38,8 +38,12 @@ source_set("flutter_windows_headers") {
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source_set("flutter_windows_source") {
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# Common Windows sources.
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sources = [
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"accessibility_alert.cc",
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"accessibility_alert.h",
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"accessibility_bridge_delegate_windows.cc",
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"accessibility_bridge_delegate_windows.h",
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"accessibility_root_node.cc",
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"accessibility_root_node.h",
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"angle_surface_manager.cc",
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"angle_surface_manager.h",
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"cursor_handler.cc",

‎shell/platform/windows/accessibility_alert.cc‎

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// Copyright 2013 The Flutter Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#include "flutter/shell/platform/windows/accessibility_alert.h"
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#include "flutter/shell/platform/windows/accessibility_root_node.h"
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namespace flutter {
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AccessibilityAlert::AccessibilityAlert() : text_(L""), parent_(nullptr) {}
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// IAccessible methods.
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IFACEMETHODIMP AccessibilityAlert::accHitTest(LONG screen_physical_pixel_x,
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LONG screen_physical_pixel_y,
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VARIANT* child) {
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child->vt = VT_EMPTY;
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return S_FALSE;
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}
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// Performs the object's default action.
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IFACEMETHODIMP AccessibilityAlert::accDoDefaultAction(VARIANT var_id) {
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return E_FAIL;
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}
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// Retrieves an IDispatch interface pointer for the specified child.
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IFACEMETHODIMP AccessibilityAlert::get_accChild(VARIANT var_child,
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IDispatch** disp_child) {
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if (V_VT(&var_child) == VT_I4 && V_I4(&var_child) == CHILDID_SELF) {
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*disp_child = this;
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AddRef();
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return S_OK;
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}
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*disp_child = nullptr;
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return E_FAIL;
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}
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// Retrieves the number of accessible children.
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IFACEMETHODIMP AccessibilityAlert::get_accChildCount(LONG* child_count) {
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*child_count = 0;
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return S_OK;
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}
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// Retrieves the tooltip description.
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IFACEMETHODIMP AccessibilityAlert::get_accDescription(VARIANT var_id,
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BSTR* desc) {
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*desc = SysAllocString(text_.c_str());
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return S_OK;
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}
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// Retrieves the name of the specified object.
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IFACEMETHODIMP AccessibilityAlert::get_accName(VARIANT var_id, BSTR* name) {
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*name = SysAllocString(text_.c_str());
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return S_OK;
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}
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// Retrieves the IDispatch interface of the object's parent.
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IFACEMETHODIMP AccessibilityAlert::get_accParent(IDispatch** disp_parent) {
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*disp_parent = parent_;
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if (*disp_parent) {
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(*disp_parent)->AddRef();
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return S_OK;
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}
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return S_FALSE;
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}
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// Retrieves information describing the role of the specified object.
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IFACEMETHODIMP AccessibilityAlert::get_accRole(VARIANT var_id, VARIANT* role) {
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*role = {.vt = VT_I4, .lVal = ROLE_SYSTEM_ALERT};
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return S_OK;
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}
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// Retrieves the current state of the specified object.
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IFACEMETHODIMP AccessibilityAlert::get_accState(VARIANT var_id,
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VARIANT* state) {
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*state = {.vt = VT_I4, .lVal = STATE_SYSTEM_DEFAULT};
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return S_OK;
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}
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// Gets the help string for the specified object.
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IFACEMETHODIMP AccessibilityAlert::get_accHelp(VARIANT var_id, BSTR* help) {
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*help = SysAllocString(L"");
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return S_OK;
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}
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// Retrieve or set the string value associated with the specified object.
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// Setting the value is not typically used by screen readers, but it's
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// used frequently by automation software.
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IFACEMETHODIMP AccessibilityAlert::get_accValue(VARIANT var_id, BSTR* value) {
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*value = SysAllocString(text_.c_str());
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return S_OK;
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}
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// IAccessible methods not implemented.
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IFACEMETHODIMP AccessibilityAlert::get_accSelection(VARIANT* selected) {
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selected->vt = VT_EMPTY;
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::accSelect(LONG flags_sel, VARIANT var_id) {
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::put_accValue(VARIANT var_id,
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BSTR new_value) {
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::get_accFocus(VARIANT* focus_child) {
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focus_child->vt = VT_EMPTY;
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::get_accHelpTopic(BSTR* help_file,
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VARIANT var_id,
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LONG* topic_id) {
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if (help_file) {
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*help_file = nullptr;
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}
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if (topic_id) {
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*topic_id = 0;
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}
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::put_accName(VARIANT var_id, BSTR put_name) {
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::get_accKeyboardShortcut(VARIANT var_id,
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BSTR* access_key) {
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*access_key = nullptr;
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::accLocation(LONG* physical_pixel_left,
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LONG* physical_pixel_top,
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LONG* width,
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LONG* height,
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VARIANT var_id) {
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::accNavigate(LONG nav_dir,
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VARIANT start,
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VARIANT* end) {
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end->vt = VT_EMPTY;
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return E_NOTIMPL;
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}
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IFACEMETHODIMP AccessibilityAlert::get_accDefaultAction(VARIANT var_id,
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BSTR* default_action) {
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*default_action = nullptr;
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return E_NOTIMPL;
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}
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// End of IAccessible methods.
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//
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// IServiceProvider implementation.
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//
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IFACEMETHODIMP AccessibilityAlert::QueryService(REFGUID guidService,
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REFIID riid,
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void** object) {
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if (!object) {
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return E_INVALIDARG;
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}
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if (guidService == IID_IAccessible) {
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return QueryInterface(riid, object);
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}
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*object = nullptr;
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return E_FAIL;
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}
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void AccessibilityAlert::SetText(const std::wstring& text) {
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text_ = text;
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}
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void AccessibilityAlert::SetParent(AccessibilityRootNode* parent) {
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parent_ = parent;
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}
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} // namespace flutter

‎shell/platform/windows/accessibility_alert.h‎

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// Copyright 2013 The Flutter Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_ACCESSIBILITY_ALERT_H_
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#define FLUTTER_SHELL_PLATFORM_WINDOWS_ACCESSIBILITY_ALERT_H_
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#include <atlbase.h>
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#include <atlcom.h>
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#include <oleacc.h>
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#include <string>
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namespace flutter {
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class AccessibilityRootNode;
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// An IAccessible node representing an alert read to the screen reader.
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// When an announcement is requested by the framework, an instance of
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// this class, if none exists already, is created and made a child of
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// the root AccessibilityRootNode node, and is therefore also a sibling
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// of the window's root node.
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// This node is not interactable to the user.
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class __declspec(uuid("778c1bd8-383f-4d49-b6be-8937e12b6a32"))
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AccessibilityAlert : public CComObjectRootEx<CComMultiThreadModel>,
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public IDispatchImpl<IAccessible>,
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public IServiceProvider {
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public:
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BEGIN_COM_MAP(AccessibilityAlert)
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COM_INTERFACE_ENTRY(AccessibilityAlert)
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COM_INTERFACE_ENTRY(IAccessible)
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COM_INTERFACE_ENTRY(IDispatch)
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COM_INTERFACE_ENTRY(IServiceProvider)
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END_COM_MAP()
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//
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// IAccessible methods.
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//
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// Retrieves the child element or child object at a given point on the screen.
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IFACEMETHODIMP accHitTest(LONG screen_physical_pixel_x,
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LONG screen_physical_pixel_y,
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VARIANT* child) override;
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// Retrieves an IDispatch interface pointer for the specified child.
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IFACEMETHODIMP get_accChild(VARIANT var_child,
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IDispatch** disp_child) override;
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// Retrieves the number of accessible children.
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IFACEMETHODIMP get_accChildCount(LONG* child_count) override;
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// Retrieves a string that describes the object's default action.
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IFACEMETHODIMP get_accDefaultAction(VARIANT var_id,
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BSTR* default_action) override;
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// Retrieves the tooltip description.
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IFACEMETHODIMP get_accDescription(VARIANT var_id, BSTR* desc) override;
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// Retrieves the name of the specified object.
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IFACEMETHODIMP get_accName(VARIANT var_id, BSTR* name) override;
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// Retrieves the IDispatch interface of the object's parent.
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IFACEMETHODIMP get_accParent(IDispatch** disp_parent) override;
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// Retrieves information describing the role of the specified object.
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IFACEMETHODIMP get_accRole(VARIANT var_id, VARIANT* role) override;
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// Retrieves the current state of the specified object.
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IFACEMETHODIMP get_accState(VARIANT var_id, VARIANT* state) override;
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// Gets the help string for the specified object.
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IFACEMETHODIMP get_accHelp(VARIANT var_id, BSTR* help) override;
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// Retrieve the string value associated with the specified object.
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IFACEMETHODIMP get_accValue(VARIANT var_id, BSTR* value) override;
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// IAccessible methods not implemented.
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IFACEMETHODIMP accLocation(LONG* physical_pixel_left,
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LONG* physical_pixel_top,
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LONG* width,
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LONG* height,
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VARIANT var_id) override;
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IFACEMETHODIMP accNavigate(LONG nav_dir,
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VARIANT start,
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VARIANT* end) override;
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IFACEMETHODIMP accDoDefaultAction(VARIANT var_id) override;
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IFACEMETHODIMP get_accFocus(VARIANT* focus_child) override;
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IFACEMETHODIMP get_accKeyboardShortcut(VARIANT var_id,
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BSTR* access_key) override;
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IFACEMETHODIMP get_accSelection(VARIANT* selected) override;
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IFACEMETHODIMP accSelect(LONG flags_sel, VARIANT var_id) override;
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IFACEMETHODIMP get_accHelpTopic(BSTR* help_file,
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VARIANT var_id,
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LONG* topic_id) override;
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IFACEMETHODIMP put_accName(VARIANT var_id, BSTR put_name) override;
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IFACEMETHODIMP put_accValue(VARIANT var_id, BSTR new_value) override;
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// End of IAccessible methods.
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//
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// IServiceProvider method.
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//
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IFACEMETHODIMP QueryService(REFGUID guidService,
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REFIID riid,
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void** object) override;
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AccessibilityAlert();
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~AccessibilityAlert() = default;
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// Sets the text of this alert to the provided message.
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void SetText(const std::wstring& text);
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void SetParent(AccessibilityRootNode* parent);
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private:
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std::wstring text_;
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AccessibilityRootNode* parent_;
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};
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} // namespace flutter
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#endif // FLUTTER_SHELL_PLATFORM_WINDOWS_ACCESSIBILITY_ALERT_H_

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