Drag-and-drop: DragEnter, DragOver, DragLeave, DragDrop

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index ff7dcb2760822be29d33c2a1151b37a967770fed..b0c64d288fd2fb44abe06b9cbd3d5939199154f5 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -38,6 +38,7 @@
 #include "content/public/common/content_features.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/context_menu_params.h"
+#include "content/public/common/drop_data.h"
 #include "content/renderer/cursor_utils.h"
 #include "content/renderer/devtools/render_widget_screen_metrics_emulator.h"
 #include "content/renderer/drop_data_builder.h"
@@ -60,6 +61,8 @@
 #include "ipc/ipc_sync_message.h"
 #include "skia/ext/platform_canvas.h"
 #include "third_party/WebKit/public/platform/WebCursorInfo.h"
+#include "third_party/WebKit/public/platform/WebDragData.h"
+#include "third_party/WebKit/public/platform/WebDragOperation.h"

[dcheng, 2016/11/09 20:23:17]

Can we clean up the corresponding forward declares / using / etc in
render_view_impl.cc?

[paulmeyer, 2016/11/09 23:19:11]

Done.

 #include "third_party/WebKit/public/platform/WebPoint.h"
 #include "third_party/WebKit/public/platform/WebRect.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
@@ -77,6 +80,7 @@
 #include "third_party/WebKit/public/web/WebView.h"
 #include "third_party/WebKit/public/web/WebWidget.h"
 #include "third_party/skia/include/core/SkShader.h"
+#include "ui/base/clipboard/clipboard.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/gfx/geometry/point_conversions.h"
 #include "ui/gfx/geometry/rect_conversions.h"
@@ -107,8 +111,10 @@
 using blink::WebCompositionUnderline;
 using blink::WebCursorInfo;
 using blink::WebDeviceEmulationParams;
+using blink::WebDragOperation;
 using blink::WebDragOperationsMask;
 using blink::WebDragData;
+using blink::WebFrameWidget;
 using blink::WebGestureEvent;
 using blink::WebImage;
 using blink::WebInputEvent;
@@ -125,12 +131,15 @@ using blink::WebPopupType;
 using blink::WebRange;
 using blink::WebRect;
 using blink::WebSize;
+using blink::WebString;
 using blink::WebTextDirection;
 using blink::WebTouchEvent;
 using blink::WebTouchPoint;
 using blink::WebVector;
 using blink::WebWidget;
 
+namespace content {
+
 namespace {
 
 typedef std::map<std::string, ui::TextInputMode> TextInputModeMap;
@@ -182,6 +191,128 @@ content::RenderWidgetInputHandlerDelegate* GetRenderWidgetInputHandlerDelegate(
   return widget;
 }
 
+WebDragData DropMetaDataToWebDragData(
+    const std::vector<DropData::Metadata>& drop_meta_data) {
+  std::vector<WebDragData::Item> item_list;
+  for (const auto& meta_data_item : drop_meta_data) {
+    if (meta_data_item.kind == DropData::Kind::STRING) {
+      WebDragData::Item item;
+      item.storageType = WebDragData::Item::StorageTypeString;
+      item.stringType = meta_data_item.mime_type;
+      // Have to pass a dummy URL here instead of an empty URL because the
+      // DropData received by browser_plugins goes through a round trip:
+      // DropData::MetaData --> WebDragData-->DropData. In the end, DropData
+      // will contain an empty URL (which means no URL is dragged) if the URL in
+      // WebDragData is empty.
+      if (base::EqualsASCII(meta_data_item.mime_type,
+                            ui::Clipboard::kMimeTypeURIList)) {
+        item.stringData = WebString::fromUTF8("about:dragdrop-placeholder");
+      }
+      item_list.push_back(item);
+      continue;
+    }
+
+    // TODO(hush): crbug.com/584789. Blink needs to support creating a file with
+    // just the mimetype. This is needed to drag files to WebView on Android
+    // platform.
+    if ((meta_data_item.kind == DropData::Kind::FILENAME) &&
+        !meta_data_item.filename.empty()) {
+      WebDragData::Item item;
+      item.storageType = WebDragData::Item::StorageTypeFilename;
+      item.filenameData = meta_data_item.filename.AsUTF16Unsafe();
+      item_list.push_back(item);
+      continue;
+    }
+
+    if (meta_data_item.kind == DropData::Kind::FILESYSTEMFILE) {
+      WebDragData::Item item;
+      item.storageType = WebDragData::Item::StorageTypeFileSystemFile;
+      item.fileSystemURL = meta_data_item.file_system_url;
+      item_list.push_back(item);
+      continue;
+    }
+  }
+
+  WebDragData result;
+  result.initialize();
+  result.setItems(item_list);
+  return result;
+}
+
+WebDragData DropDataToWebDragData(const DropData& drop_data) {
+  std::vector<WebDragData::Item> item_list;
+
+  // These fields are currently unused when dragging into WebKit.
+  DCHECK(drop_data.download_metadata.empty());
+  DCHECK(drop_data.file_contents.empty());
+  DCHECK(drop_data.file_description_filename.empty());
+
+  if (!drop_data.text.is_null()) {
+    WebDragData::Item item;
+    item.storageType = WebDragData::Item::StorageTypeString;
+    item.stringType = WebString::fromUTF8(ui::Clipboard::kMimeTypeText);
+    item.stringData = drop_data.text.string();
+    item_list.push_back(item);
+  }
+
+  if (!drop_data.url.is_empty()) {
+    WebDragData::Item item;
+    item.storageType = WebDragData::Item::StorageTypeString;
+    item.stringType = WebString::fromUTF8(ui::Clipboard::kMimeTypeURIList);
+    item.stringData = WebString::fromUTF8(drop_data.url.spec());
+    item.title = drop_data.url_title;
+    item_list.push_back(item);
+  }
+
+  if (!drop_data.html.is_null()) {
+    WebDragData::Item item;
+    item.storageType = WebDragData::Item::StorageTypeString;
+    item.stringType = WebString::fromUTF8(ui::Clipboard::kMimeTypeHTML);
+    item.stringData = drop_data.html.string();
+    item.baseURL = drop_data.html_base_url;
+    item_list.push_back(item);
+  }
+
+  for (std::vector<ui::FileInfo>::const_iterator it =
+           drop_data.filenames.begin();
+       it != drop_data.filenames.end();
+       ++it) {
+    WebDragData::Item item;
+    item.storageType = WebDragData::Item::StorageTypeFilename;
+    item.filenameData = it->path.AsUTF16Unsafe();
+    item.displayNameData = it->display_name.AsUTF16Unsafe();
+    item_list.push_back(item);
+  }
+
+  for (std::vector<DropData::FileSystemFileInfo>::const_iterator it =
+           drop_data.file_system_files.begin();
+       it != drop_data.file_system_files.end();
+       ++it) {
+    WebDragData::Item item;
+    item.storageType = WebDragData::Item::StorageTypeFileSystemFile;
+    item.fileSystemURL = it->url;
+    item.fileSystemFileSize = it->size;
+    item_list.push_back(item);
+  }
+
+  for (std::map<base::string16, base::string16>::const_iterator it =
+           drop_data.custom_data.begin();
+       it != drop_data.custom_data.end();
+       ++it) {
+    WebDragData::Item item;
+    item.storageType = WebDragData::Item::StorageTypeString;
+    item.stringType = it->first;
+    item.stringData = it->second;
+    item_list.push_back(item);
+  }
+
+  WebDragData result;
+  result.initialize();
+  result.setItems(item_list);
+  result.setFilesystemId(drop_data.filesystem_id);
+  return result;
+}
+
 content::RenderWidget::CreateRenderWidgetFunction g_create_render_widget =
     nullptr;
 
@@ -204,8 +335,6 @@ ui::TextInputMode ConvertWebTextInputMode(blink::WebTextInputMode mode) {
 
 }  // namespace
 
-namespace content {
-
 // RenderWidget ---------------------------------------------------------------
 
 RenderWidget::RenderWidget(CompositorDependencies* compositor_deps,
@@ -520,12 +649,16 @@ bool RenderWidget::OnMessageReceived(const IPC::Message& message) {
                         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)
 #if defined(OS_ANDROID)
     IPC_MESSAGE_HANDLER(InputMsg_ImeEventAck, OnImeEventAck)
     IPC_MESSAGE_HANDLER(InputMsg_RequestTextInputStateUpdate,
                         OnRequestTextInputStateUpdate)
 #endif
-    IPC_MESSAGE_HANDLER(ViewMsg_HandleCompositorProto, OnHandleCompositorProto)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -1530,6 +1663,60 @@ void RenderWidget::OnHandleCompositorProto(const std::vector<uint8_t>& proto) {
     compositor_->OnHandleCompositorProto(proto);
 }
 
+void RenderWidget::OnDragTargetDragEnter(
+    const std::vector<DropData::Metadata>& drop_meta_data,
+    const gfx::Point& client_point,
+    const gfx::Point& screen_point,
+    WebDragOperationsMask ops,
+    int key_modifiers) {
+  if (!GetWebWidget())

[dcheng, 2016/11/09 20:23:17]

How come this needs to do null checks, but RenderView didn't need to?

[paulmeyer, 2016/11/09 23:19:11]

It seems to be possible for this message to come during shutdown, and should be
ignored in that case.

+    return;
+
+  DCHECK(GetWebWidget()->isWebFrameWidget());
+  WebDragOperation operation = static_cast<WebFrameWidget*>(GetWebWidget())->
+      dragTargetDragEnter(DropMetaDataToWebDragData(drop_meta_data),
+                          client_point, screen_point, ops, key_modifiers);
+
+  Send(new DragHostMsg_UpdateDragCursor(routing_id(), operation));
+}
+
+void RenderWidget::OnDragTargetDragOver(const gfx::Point& client_point,
+                                        const gfx::Point& screen_point,
+                                        WebDragOperationsMask ops,
+                                        int key_modifiers) {
+  if (!GetWebWidget())
+    return;
+
+  DCHECK(GetWebWidget()->isWebFrameWidget());
+  WebDragOperation operation =
+      static_cast<WebFrameWidget*>(GetWebWidget())->dragTargetDragOver(
+          ConvertWindowPointToViewport(client_point),
+          screen_point, ops, key_modifiers);
+
+  Send(new DragHostMsg_UpdateDragCursor(routing_id(), operation));
+}
+
+void RenderWidget::OnDragTargetDragLeave() {
+  if (!GetWebWidget())
+    return;
+  DCHECK(GetWebWidget()->isWebFrameWidget());
+  static_cast<WebFrameWidget*>(GetWebWidget())->dragTargetDragLeave();
+}
+
+void RenderWidget::OnDragTargetDrop(const DropData& drop_data,
+                                    const gfx::Point& client_point,
+                                    const gfx::Point& screen_point,
+                                    int key_modifiers) {
+  if (!GetWebWidget())
+    return;
+
+  DCHECK(GetWebWidget()->isWebFrameWidget());
+  static_cast<WebFrameWidget*>(GetWebWidget())->dragTargetDrop(
+      DropDataToWebDragData(drop_data),
+      ConvertWindowPointToViewport(client_point),
+      screen_point, key_modifiers);
+}
+
 void RenderWidget::showImeIfNeeded() {
 #if defined(OS_ANDROID) || defined(USE_AURA)
   UpdateTextInputState(ShowIme::IF_NEEDED, ChangeSource::FROM_NON_IME);
@@ -2067,6 +2254,13 @@ float RenderWidget::GetOriginalDeviceScaleFactor() const {
       device_scale_factor_;
 }
 
+gfx::Point RenderWidget::ConvertWindowPointToViewport(
+    const gfx::Point& point) {
+  blink::WebFloatRect point_in_viewport(point.x(), point.y(), 0, 0);
+  convertWindowToViewport(&point_in_viewport);
+  return gfx::Point(point_in_viewport.x, point_in_viewport.y);
+}
+
 bool RenderWidget::requestPointerLock() {
   return mouse_lock_dispatcher_->LockMouse(webwidget_mouse_lock_target_.get());
 }
@@ -2090,7 +2284,7 @@ void RenderWidget::startDragging(blink::WebReferrerPolicy policy,
   DropData drop_data(DropDataBuilder::Build(data));
   drop_data.referrer_policy = policy;
   gfx::Vector2d imageOffset(offset_in_window.x, offset_in_window.y);
-  Send(new DragHostMsg_StartDragging(routing_id_, drop_data, mask,
+  Send(new DragHostMsg_StartDragging(routing_id(), drop_data, mask,
                                      image.getSkBitmap(), imageOffset,
                                      possible_drag_event_info_));
 }