Drag-and-drop: dragSourceEndedAt, dragSourceSystemDragEnded

content/renderer/render_widget.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/render_widget.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/auto_reset.h"
@@ skipping 613 matching lines @@
     IPC_MESSAGE_HANDLER(ViewMsg_UpdateScreenRects, OnUpdateScreenRects)
     IPC_MESSAGE_HANDLER(ViewMsg_WaitForNextFrameForTests,
                         OnWaitNextFrameForTests)
     IPC_MESSAGE_HANDLER(InputMsg_RequestCompositionUpdate,
                         OnRequestCompositionUpdate)
     IPC_MESSAGE_HANDLER(ViewMsg_HandleCompositorProto, OnHandleCompositorProto)
     IPC_MESSAGE_HANDLER(DragMsg_TargetDragEnter, OnDragTargetDragEnter)
     IPC_MESSAGE_HANDLER(DragMsg_TargetDragOver, OnDragTargetDragOver)
     IPC_MESSAGE_HANDLER(DragMsg_TargetDragLeave, OnDragTargetDragLeave)
     IPC_MESSAGE_HANDLER(DragMsg_TargetDrop, OnDragTargetDrop)
+    IPC_MESSAGE_HANDLER(DragMsg_SourceEnded, OnDragSourceEnded)
+    IPC_MESSAGE_HANDLER(DragMsg_SourceSystemDragEnded,
+                        OnDragSourceSystemDragEnded)
 #if defined(OS_ANDROID)
     IPC_MESSAGE_HANDLER(InputMsg_ImeEventAck, OnImeEventAck)
     IPC_MESSAGE_HANDLER(InputMsg_RequestTextInputStateUpdate,
                         OnRequestTextInputStateUpdate)
 #endif
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
@@ skipping 1055 matching lines @@
   if (!GetWebWidget())
     return;
 
   DCHECK(GetWebWidget()->isWebFrameWidget());
   static_cast<WebFrameWidget*>(GetWebWidget())->dragTargetDrop(
       DropDataToWebDragData(drop_data),
       ConvertWindowPointToViewport(client_point),
       screen_point, key_modifiers);
 }
 
+void RenderWidget::OnDragSourceEnded(const gfx::Point& client_point,
+                                     const gfx::Point& screen_point,
+                                     WebDragOperation op) {

[ncarter (slow), 2016/11/14 23:21:37]

RenderWidget::OnDragTargetDrop seems to defend against the !GetWebWidget() case.
Do you know why, and if so, do we need to do that here?

From looking at the code we probably don't need it -- during normal operation,
GetWebWidget() ought to be a valid pointer between Init and Close(). Init is
also where the widget becomes added to the routing map, and the widget is
removed from the routing map before Close() happens.

[paulmeyer, 2016/11/15 01:20:31]

Good catch. I believe it is actually needed. If you look at other functions (not
written by me) in this file, it seems to be possible for these messages to come
through when GetWebWdiget() is null. I will add the check. dcheng@ noticed this
as well and said that something should be fixed about this in the future, but to
leave the checks in for now.

+  static_cast<WebFrameWidget*>(GetWebWidget())->dragSourceEndedAt(
+      ConvertWindowPointToViewport(client_point), screen_point, op);
+}
+
+void RenderWidget::OnDragSourceSystemDragEnded() {
+  static_cast<WebFrameWidget*>(GetWebWidget())->dragSourceSystemDragEnded();
+}
+
 void RenderWidget::showImeIfNeeded() {
 #if defined(OS_ANDROID) || defined(USE_AURA)
   UpdateTextInputState(ShowIme::IF_NEEDED, ChangeSource::FROM_NON_IME);
 #endif
 
 // TODO(rouslan): Fix ChromeOS and Windows 8 behavior of autofill popup with
 // virtual keyboard.
 #if !defined(OS_ANDROID)
   FocusChangeComplete();
 #endif
@@ skipping 567 matching lines @@
 blink::WebInputMethodController* RenderWidget::GetInputMethodController()
     const {
   // TODO(ekaramad): Remove this CHECK when GetWebWidget() is
   // always a WebFrameWidget.
   CHECK(GetWebWidget()->isWebFrameWidget());
   return static_cast<blink::WebFrameWidget*>(GetWebWidget())
       ->getActiveWebInputMethodController();
 }
 
 }  // namespace content