- Add CefDragHandler to support examination of drag data and cancellation of drag requests (issue #297).

- Mac: Fix dragging of URLs by providing a default image if no drag image is supplied.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@279 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef/browser_webkit_glue.h

@@ -15,6 +15,10 @@ class WebFrame;
 class WebView;
 }
 
+#if defined(OS_MACOSX)
+class FilePath;
+#endif
+
 namespace webkit_glue {
 
 #if defined(OS_WIN)
@@ -28,6 +32,7 @@ BOOL SaveBitmapToFile(HBITMAP hBmp, HDC hDC, LPCTSTR file, LPBYTE lpBits);
   
 #if defined(OS_MACOSX)
 void InitializeDataPak();
+FilePath GetResourcesFilePath();
 #endif
 
 // Text encoding objects must be initialized on the main thread.

libcef/browser_webview_delegate_mac.mm

@@ -5,6 +5,7 @@
 #include "browser_webview_delegate.h"
 #import "browser_webview_mac.h"
 #include "browser_impl.h"
+#include "drag_data_impl.h"
 #import "include/cef_application_mac.h"
 
 #import <Cocoa/Cocoa.h>
@@ -138,6 +139,21 @@ void BrowserWebViewDelegate::startDragging(const WebDragData& data,
   if (!view)
     return;
   
+  WebDropData drop_data(data);
+
+  CefRefPtr<CefClient> client = browser_->GetClient();
+  if (client.get()) {
+    CefRefPtr<CefDragHandler> handler = client->GetDragHandler();
+    if (handler.get()) {
+      CefRefPtr<CefDragData> data(new CefDragDataImpl(drop_data));
+      if (handler->OnDragStart(browser_, data,
+              static_cast<CefDragHandler::DragOperationsMask>(mask))) {
+        browser_->UIT_GetWebView()->dragSourceSystemDragEnded();
+        return;
+      }
+    }
+  }
+
   // By allowing nested tasks, the code below also allows Close(),
   // which would deallocate |this|.  The same problem can occur while
   // processing -sendEvent:, so Close() is deferred in that case.
@@ -148,13 +164,16 @@ void BrowserWebViewDelegate::startDragging(const WebDragData& data,
   // The drag invokes a nested event loop, arrange to continue
   // processing events.
   MessageLoop::ScopedNestableTaskAllower allow(MessageLoop::current());
-  NSDragOperation op_mask = static_cast<NSDragOperation>(mask);
-  const SkBitmap& bitmap = gfx::CGImageToSkBitmap(image.getCGImageRef());
-  CGColorSpaceRef color_space = base::mac::GetSystemColorSpace();
-  NSImage* ns_image = gfx::SkBitmapToNSImageWithColorSpace(bitmap, color_space);
+  
+  NSImage* ns_image = nil;
+  if (!image.isNull()) {
+    const SkBitmap& bitmap = gfx::CGImageToSkBitmap(image.getCGImageRef());
+    CGColorSpaceRef color_space = base::mac::GetSystemColorSpace();
+    ns_image = gfx::SkBitmapToNSImageWithColorSpace(bitmap, color_space);
+  }
   NSPoint offset = NSPointFromCGPoint(gfx::Point(image_offset).ToCGPoint());
-  [view startDragWithDropData:WebDropData(data)
-            dragOperationMask:op_mask
+  [view startDragWithDropData:drop_data
+            dragOperationMask:static_cast<NSDragOperation>(mask)
                         image:ns_image
                        offset:offset];
 }

libcef/browser_webview_delegate_win.cc

@@ -12,6 +12,7 @@
 #include "browser_impl.h"
 #include "browser_webview_delegate.h"
 #include "cef_context.h"
+#include "drag_data_impl.h"
 #include "web_drop_target_win.h"
 
 #include <objidl.h>
@@ -190,8 +191,23 @@ void BrowserWebViewDelegate::startDragging(
     return;
   }
 
+  WebDropData drop_data(data);
+
+  CefRefPtr<CefClient> client = browser_->GetClient();
+  if (client.get()) {
+    CefRefPtr<CefDragHandler> handler = client->GetDragHandler();
+    if (handler.get()) {
+      CefRefPtr<CefDragData> data(new CefDragDataImpl(drop_data));
+      if (handler->OnDragStart(browser_, data,
+              static_cast<CefDragHandler::DragOperationsMask>(mask))) {
+        EndDragging();
+        return;
+      }
+    }
+  }
+
   drag_delegate_ = new BrowserDragDelegate(this);
-  drag_delegate_->StartDragging(WebDropData(data), mask, image.getSkBitmap(),
+  drag_delegate_->StartDragging(drop_data, mask, image.getSkBitmap(),
                                 image_offset);
 }
 
@@ -563,8 +579,7 @@ end:
 
 void BrowserWebViewDelegate::RegisterDragDrop() {
   DCHECK(!drop_target_);
-  drop_target_ = new WebDropTarget(browser_->UIT_GetWebViewWndHandle(),
-                                   browser_->UIT_GetWebView());
+  drop_target_ = new WebDropTarget(browser_);
 }
 
 void BrowserWebViewDelegate::RevokeDragDrop() {

libcef/drag_data_impl.cc

@@ -0,0 +1,78 @@
+// Copyright (c) 2011 The Chromium Embedded Framework 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 "drag_data_impl.h"
+
+CefDragDataImpl::CefDragDataImpl(const WebDropData& data)
+  : data_(data)
+{
+}
+  
+bool CefDragDataImpl::IsLink()
+{
+  return (data_.url.is_valid() && data_.file_extension.empty());
+}
+
+bool CefDragDataImpl::IsFragment()
+{
+  return (!data_.url.is_valid() && data_.file_extension.empty() &&
+          data_.filenames.empty());
+}
+
+bool CefDragDataImpl::IsFile()
+{
+  return (!data_.file_extension.empty() || !data_.filenames.empty());
+}
+
+CefString CefDragDataImpl::GetLinkURL()
+{
+  return data_.url.spec();
+}
+
+CefString CefDragDataImpl::GetLinkTitle()
+{
+  return data_.url_title;
+}
+
+CefString CefDragDataImpl::GetLinkMetadata()
+{
+  return data_.download_metadata;
+}
+
+CefString CefDragDataImpl::GetFragmentText()
+{
+  return data_.plain_text;
+}
+
+CefString CefDragDataImpl::GetFragmentHtml()
+{
+  return data_.text_html;
+}
+
+CefString CefDragDataImpl::GetFragmentBaseURL()
+{
+  return data_.html_base_url.spec();
+}
+
+CefString CefDragDataImpl::GetFileExtension()
+{
+  return data_.file_extension;
+}
+
+CefString CefDragDataImpl::GetFileName()
+{
+  return data_.file_description_filename;
+}
+
+bool CefDragDataImpl::GetFileNames(std::vector<CefString>& names)
+{
+  if (data_.filenames.empty())
+    return false;
+
+  std::vector<string16>::const_iterator it = data_.filenames.begin();
+  for (; it != data_.filenames.end(); ++it)
+    names.push_back(*it);
+
+  return true;
+}

libcef/drag_data_impl.h

@@ -0,0 +1,36 @@
+// Copyright (c) 2011 The Chromium Embedded Framework Authors. All rights
+// reserved. Use of this source code is governed by a BSD-style license that
+// can be found in the LICENSE file.
+
+#ifndef _DRAG_DATA_IMPL_H
+#define _DRAG_DATA_IMPL_H
+
+#include "../include/cef.h"
+#include "webkit/glue/webdropdata.h"
+
+// Implementation of CefDragData.
+class CefDragDataImpl : public CefDragData
+{
+public:
+  explicit CefDragDataImpl(const WebDropData& data);
+
+  virtual bool IsLink();
+  virtual bool IsFragment();
+  virtual bool IsFile();
+  virtual CefString GetLinkURL();
+  virtual CefString GetLinkTitle();
+  virtual CefString GetLinkMetadata();
+  virtual CefString GetFragmentText();
+  virtual CefString GetFragmentHtml();
+  virtual CefString GetFragmentBaseURL();
+  virtual CefString GetFileExtension();
+  virtual CefString GetFileName();
+  virtual bool GetFileNames(std::vector<CefString>& names);
+
+protected:
+  WebDropData data_;
+
+  IMPLEMENT_REFCOUNTING(CefDragDataImpl);
+};
+
+#endif // _DRAG_DATA_IMPL_H

libcef/web_drag_source_mac.mm

@@ -4,6 +4,7 @@
 // found in the LICENSE file.
 
 #include "browser_impl.h"
+#include "browser_webkit_glue.h"
 #import "browser_webview_mac.h"
 #include "drag_download_util.h"
 #include "download_util.h"
@@ -140,6 +141,14 @@ void PromiseWriterTask::Run() {
     dropData_.reset(new WebDropData(*dropData));
     DCHECK(dropData_.get());
 
+    if (image == nil) {
+      // No drag image was provided so create one.
+      FilePath path = webkit_glue::GetResourcesFilePath();
+      path = path.AppendASCII("urlIcon.png");
+      image = [[NSImage alloc]
+               initWithContentsOfFile:SysUTF8ToNSString(path.value())];
+    }
+
     dragImage_.reset([image retain]);
     imageOffset_ = offset;
 

libcef/web_drop_target_mac.mm

@@ -6,6 +6,7 @@
 #include "browser_impl.h"
 #import "browser_webview_mac.h"
 #include "cef_context.h"
+#include "drag_data_impl.h"
 #import "web_drop_target_mac.h"
 #import "web_drag_utils_mac.h"
 
@@ -30,8 +31,10 @@ using WebKit::WebView;
 // drag&drop messages to WebCore and handle navigation on a successful drop
 // (if necessary).
 - (id)initWithWebView:(BrowserWebView*)view {
-  if ((self = [super init]))
+  if ((self = [super init])) {
     view_ = view;
+    canceled_ = false;
+  }
   return self;
 }
 
@@ -86,17 +89,34 @@ using WebKit::WebView;
   WebView* webview = view_.browser->UIT_GetWebView();
 
   // Fill out a WebDropData from pasteboard.
-  WebDropData data;
-  [self populateWebDropData:&data fromPasteboard:[info draggingPasteboard]];
+  WebDropData drop_data;
+  [self populateWebDropData:&drop_data
+             fromPasteboard:[info draggingPasteboard]];
+  
+  NSDragOperation mask = [info draggingSourceOperationMask];
+  
+  canceled_ = false;
+  
+  CefRefPtr<CefClient> client = view_.browser->GetClient();
+  if (client.get()) {
+    CefRefPtr<CefDragHandler> handler = client->GetDragHandler();
+    if (handler.get()) {
+      CefRefPtr<CefDragData> data(new CefDragDataImpl(drop_data));
+      if (handler->OnDragEnter(view_.browser, data,
+              static_cast<CefDragHandler::DragOperationsMask>(mask))) {
+        canceled_ = true;
+        return NSDragOperationNone;
+      }
+    }
+  }
 
   // Create the appropriate mouse locations for WebCore. The draggingLocation
   // is in window coordinates. Both need to be flipped.
   NSPoint windowPoint = [info draggingLocation];
   NSPoint viewPoint = [self flipWindowPointToView:windowPoint view:view];
   NSPoint screenPoint = [self flipWindowPointToScreen:windowPoint view:view];
-  NSDragOperation mask = [info draggingSourceOperationMask];
   WebDragOperation op =
-      webview->dragTargetDragEnter(data.ToDragData(),
+      webview->dragTargetDragEnter(drop_data.ToDragData(),
                                    WebPoint(viewPoint.x, viewPoint.y),
                                    WebPoint(screenPoint.x, screenPoint.y),
                                    static_cast<WebDragOperationsMask>(mask));
@@ -108,6 +128,9 @@ using WebKit::WebView;
   if (current_wvh_ != _Context->current_webviewhost())
     return;
 
+  if (canceled_)
+    return;
+
   WebView* webview = view_.browser->UIT_GetWebView();
   
   // Nothing to do in the interstitial case.
@@ -127,6 +150,9 @@ using WebKit::WebView;
     return NSDragOperationNone;
   }
 
+  if (canceled_)
+    return NSDragOperationNone;
+
   WebView* webview = view_.browser->UIT_GetWebView();
   
   // Create the appropriate mouse locations for WebCore. The draggingLocation

libcef/web_drop_target_win.cc

@@ -3,9 +3,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "web_drop_target_win.h"
+#include "browser_impl.h"
 #include "cef_context.h"
+#include "drag_data_impl.h"
 #include "web_drag_utils_win.h"
+#include "web_drop_target_win.h"
 
 #include <windows.h>
 #include <shlobj.h>
@@ -28,6 +30,7 @@ using WebKit::WebDragOperationLink;
 using WebKit::WebDragOperationMove;
 using WebKit::WebDragOperationGeneric;
 using WebKit::WebPoint;
+using WebKit::WebView;
 
 namespace {
 
@@ -44,11 +47,12 @@ DWORD GetPreferredDropEffect(DWORD effect) {
 
 }  // namespace
 
-WebDropTarget::WebDropTarget(HWND source_hwnd, WebKit::WebView* view)
-    : ui::DropTarget(source_hwnd),
-      view_(view),
+WebDropTarget::WebDropTarget(CefBrowserImpl* browser)
+    : ui::DropTarget(browser->UIT_GetWebViewWndHandle()),
+      browser_(browser),
       current_wvh_(NULL),
-      drag_cursor_(WebDragOperationNone) {
+      drag_cursor_(WebDragOperationNone),
+      canceled_(false) {
 }
 
 WebDropTarget::~WebDropTarget() {
@@ -69,15 +73,33 @@ DWORD WebDropTarget::OnDragEnter(IDataObject* data_object,
   if (drop_data.url.is_empty())
     ui::OSExchangeDataProviderWin::GetPlainTextURL(data_object, &drop_data.url);
 
+  WebKit::WebDragOperationsMask mask =
+      web_drag_utils_win::WinDragOpMaskToWebDragOpMask(effects);
+
+  canceled_ = false;
+
+  CefRefPtr<CefClient> client = browser_->GetClient();
+  if (client.get()) {
+    CefRefPtr<CefDragHandler> handler = client->GetDragHandler();
+    if (handler.get()) {
+      CefRefPtr<CefDragData> data(new CefDragDataImpl(drop_data));
+      if (handler->OnDragEnter(browser_, data,
+              static_cast<CefDragHandler::DragOperationsMask>(mask))) {
+        canceled_ = true;
+        return DROPEFFECT_NONE;
+      }
+    }
+  }
+
   drag_cursor_ = WebDragOperationNone;
 
   POINT client_pt = cursor_position;
   ScreenToClient(GetHWND(), &client_pt);
-  WebDragOperation operation = view_->dragTargetDragEnter(
+  WebDragOperation operation = browser_->UIT_GetWebView()->dragTargetDragEnter(
       drop_data.ToDragData(),
       WebPoint(client_pt.x, client_pt.y),
       WebPoint(cursor_position.x, cursor_position.y),
-      web_drag_utils_win::WinDragOpMaskToWebDragOpMask(effects));
+      mask);
 
   return web_drag_utils_win::WebDragOpToWinDragOp(operation);
 }
@@ -90,9 +112,12 @@ DWORD WebDropTarget::OnDragOver(IDataObject* data_object,
   if (current_wvh_ != _Context->current_webviewhost())
     OnDragEnter(data_object, key_state, cursor_position, effects);
 
+  if (canceled_)
+    return DROPEFFECT_NONE;
+
   POINT client_pt = cursor_position;
   ScreenToClient(GetHWND(), &client_pt);
-  WebDragOperation operation = view_->dragTargetDragOver(
+  WebDragOperation operation = browser_->UIT_GetWebView()->dragTargetDragOver(
       WebPoint(client_pt.x, client_pt.y),
       WebPoint(cursor_position.x, cursor_position.y),
       web_drag_utils_win::WinDragOpMaskToWebDragOpMask(effects));
@@ -105,7 +130,10 @@ void WebDropTarget::OnDragLeave(IDataObject* data_object) {
   if (current_wvh_ != _Context->current_webviewhost())
     return;
 
-  view_->dragTargetDragLeave();
+  if (canceled_)
+    return;
+
+  browser_->UIT_GetWebView()->dragTargetDragLeave();
 }
 
 DWORD WebDropTarget::OnDrop(IDataObject* data_object,
@@ -118,7 +146,7 @@ DWORD WebDropTarget::OnDrop(IDataObject* data_object,
 
   POINT client_pt = cursor_position;
   ScreenToClient(GetHWND(), &client_pt);
-  view_->dragTargetDrop(
+  browser_->UIT_GetWebView()->dragTargetDrop(
       WebPoint(client_pt.x, client_pt.y),
       WebPoint(cursor_position.x, cursor_position.y));
 

libcef/web_drop_target_win.h

@@ -11,9 +11,7 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDragOperation.h"
 #include "ui/base/dragdrop/drop_target.h"
 
-namespace WebKit {
-class WebView;
-};
+class CefBrowserImpl;
 class WebViewHost;
 
 // A helper object that provides drop capabilities to a WebView. The
@@ -23,7 +21,7 @@ class WebDropTarget : public ui::DropTarget {
  public:
   // Create a new WebDropTarget associating it with the given HWND and
   // WebView.
-  WebDropTarget(HWND source_hwnd, WebKit::WebView* view);
+  WebDropTarget(CefBrowserImpl* browser);
   virtual ~WebDropTarget();
 
   void set_drag_cursor(WebKit::WebDragOperation op) {
@@ -49,8 +47,8 @@ class WebDropTarget : public ui::DropTarget {
                        DWORD effect);
 
  private:
-  // Our associated WebView.
-  WebKit::WebView* view_;
+  // Our associated CefBrowserImpl.
+  CefBrowserImpl* browser_;
 
   // We keep track of the web view host we're dragging over.  If it changes
   // during a drag, we need to re-send the DragEnter message.  WARNING:
@@ -62,6 +60,9 @@ class WebDropTarget : public ui::DropTarget {
   // content area.  This can be updated async during a drag operation.
   WebKit::WebDragOperation drag_cursor_;
 
+  // True if the drag has been canceled.
+  bool canceled_;
+
   DISALLOW_COPY_AND_ASSIGN(WebDropTarget);
 };