Fix WebView compositor input handling

android_webview/browser/in_process_renderer/in_process_view_renderer.cc

 // Copyright (c) 2013 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 "android_webview/browser/in_process_renderer/in_process_view_renderer.h"
 
 #include <android/bitmap.h>
 
 #include "android_webview/public/browser/draw_gl.h"
 #include "android_webview/public/browser/draw_sw.h"
 #include "base/android/jni_android.h"
 #include "base/logging.h"
 #include "content/public/browser/android/content_view_core.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/renderer/android/synchronous_compositor.h"
+#include "content/public/renderer/android/synchronous_input_event_handler.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkDevice.h"
 #include "third_party/skia/include/core/SkGraphics.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "ui/gfx/size_conversions.h"
 #include "ui/gfx/transform.h"
 #include "ui/gfx/vector2d_f.h"
 #include "ui/gl/gl_bindings.h"
 
@@ skipping 76 matching lines @@
   return true;
 }
 
 }  // namespace
 
 InProcessViewRenderer::InProcessViewRenderer(
     BrowserViewRenderer::Client* client,
     JavaHelper* java_helper)
     : client_(client),
       java_helper_(java_helper),
+      content_view_core_(NULL),
       web_contents_(NULL),
       compositor_(NULL),
+      input_event_handler_(NULL),
       view_visible_(false),
       continuous_invalidate_(false),
       continuous_invalidate_task_pending_(false),
       width_(0),
       height_(0),
       attached_to_window_(false),
       hardware_initialized_(false),
       hardware_failed_(false),
       egl_context_at_init_(NULL),
       weak_factory_(this) {
@@ skipping 28 matching lines @@
     compositor_->SetClient(NULL);
   compositor_ = compositor;
   hardware_initialized_ = false;
   hardware_failed_ = false;
   compositor_->SetClient(this);
 
   if (attached_to_window_)
     client_->RequestProcessMode();
 }
 
+void InProcessViewRenderer::BindSynchronousInputEventHandler(
+    content::SynchronousInputEventHandler* input_event_handler) {
+  input_event_handler_ = input_event_handler;
+}
+
 void InProcessViewRenderer::SetContents(
     content::ContentViewCore* content_view_core) {
   // First remove association from the prior ContentViewCore / WebContents.
+  if (content_view_core_) {
+    content_view_core_->SetInputEventFilterCallback(
+        ContentViewCore::InputEventFilterCallback());
+  }
+
   if (web_contents_) {
     web_contents_->SetUserData(kUserDataKey, NULL);
     DCHECK(!web_contents_);  // WebContentsGone should have been called.
   }
 
-  if (!content_view_core)
+  content_view_core_ = content_view_core;
+  if (!content_view_core_)
     return;
 
+  content_view_core_->SetInputEventFilterCallback(
+      base::Bind(&InProcessViewRenderer::HandleInputEvent,
+                 base::Unretained(this)));

[jamesr, 2013/05/24 23:46:16]

what prevents this callback from being invoked after |this| has gone away?

[jdduke (slow), 2013/05/25 01:22:11]

The assumption (which I should probably specify in the ContentViewCore method
contract) is that a call to ContentViewCore::SetInputEventFilterCallback() with
a null callback will clear any that have been previously supplied.  When |this|
is destroyed, we call SetContents(NULL), which should clear any outstanding
callback on a valid content_view_core_.  Of course, this assumes
content_view_core_ is a valid handle by such time.  

+
   web_contents_ = content_view_core->GetWebContents();
   web_contents_->SetUserData(kUserDataKey, new UserData(this));
 }
 
 void InProcessViewRenderer::WebContentsGone() {
   web_contents_ = NULL;
 }
 
 bool InProcessViewRenderer::PrepareDrawGL(int x, int y) {
   // No harm in updating |hw_rendering_scroll_| even if we return false.
@@ skipping 238 matching lines @@
 bool InProcessViewRenderer::RenderSW(SkCanvas* canvas) {
   // TODO(joth): BrowserViewRendererImpl had a bunch of logic for dpi and page
   // scale here. Determine what if any needs bringing over to this class.
   return CompositeSW(canvas);
 }
 
 bool InProcessViewRenderer::CompositeSW(SkCanvas* canvas) {
   return compositor_ && compositor_->DemandDrawSw(canvas);
 }
 
+content::InputEventAckState InProcessViewRenderer::HandleInputEvent(
+    int routing_id,
+    const WebKit::WebInputEvent& input_event) {
+  if (!input_event_handler_)
+    return content::INPUT_EVENT_ACK_STATE_NOT_CONSUMED;
+
+  return input_event_handler_->HandleInputEvent(routing_id, &input_event);
+}
+
+
 }  // namespace android_webview