cef/libcef/renderer/extensions/print_render_frame_helper_delegate.cc
Ananyo Maiti 1669c0afbd Add print preview support (see issue #123)
Pass the `--enable-print-preview` command-line flag to enable. Currently only
supported on Windows and Linux.
2019-07-19 21:55:30 -04:00

82 lines
2.9 KiB
C++

// Copyright 2015 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 "libcef/renderer/extensions/print_render_frame_helper_delegate.h"
#include <vector>
#include "libcef/common/extensions/extensions_util.h"
#include "base/command_line.h"
#include "base/strings/string_util.h"
#include "chrome/common/chrome_switches.h"
#include "chrome/common/extensions/extension_constants.h"
#include "chrome/common/url_constants.h"
#include "content/public/renderer/render_frame.h"
#include "extensions/common/constants.h"
#include "extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.h"
#include "services/service_manager/public/cpp/interface_provider.h"
#include "third_party/blink/public/web/web_document.h"
#include "third_party/blink/public/web/web_element.h"
#include "third_party/blink/public/web/web_local_frame.h"
namespace extensions {
CefPrintRenderFrameHelperDelegate::CefPrintRenderFrameHelperDelegate(
bool is_windowless)
: is_windowless_(is_windowless) {}
CefPrintRenderFrameHelperDelegate::~CefPrintRenderFrameHelperDelegate() {}
bool CefPrintRenderFrameHelperDelegate::CancelPrerender(
content::RenderFrame* render_frame) {
return false;
}
// Return the PDF object element if |frame| is the out of process PDF extension.
blink::WebElement CefPrintRenderFrameHelperDelegate::GetPdfElement(
blink::WebLocalFrame* frame) {
GURL url = frame->GetDocument().Url();
bool inside_print_preview = url.GetOrigin() == chrome::kChromeUIPrintURL;
bool inside_pdf_extension =
url.SchemeIs(extensions::kExtensionScheme) &&
url.host_piece() == extension_misc::kPdfExtensionId;
if (inside_print_preview || inside_pdf_extension) {
// <object> with id="plugin" is created in
// chrome/browser/resources/pdf/pdf.js.
auto plugin_element = frame->GetDocument().GetElementById("plugin");
if (!plugin_element.IsNull()) {
return plugin_element;
}
NOTREACHED();
}
return blink::WebElement();
}
bool CefPrintRenderFrameHelperDelegate::IsPrintPreviewEnabled() {
return !is_windowless_ && PrintPreviewEnabled();
}
bool CefPrintRenderFrameHelperDelegate::OverridePrint(
blink::WebLocalFrame* frame) {
if (!frame->GetDocument().IsPluginDocument())
return false;
auto* post_message_support =
extensions::PostMessageSupport::FromWebLocalFrame(frame);
if (post_message_support) {
// This message is handled in chrome/browser/resources/pdf/pdf.js and
// instructs the PDF plugin to print. This is to make window.print() on a
// PDF plugin document correctly print the PDF. See
// https://crbug.com/448720.
base::DictionaryValue message;
message.SetString("type", "print");
post_message_support->PostMessageFromValue(message);
return true;
}
return false;
}
} // namespace extensions