download_saveimage流程

最新推荐文章于 2025-02-24 00:15:00 发布

wslixb

最新推荐文章于 2025-02-24 00:15:00 发布

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文章标签： chromium

本文链接：https://blog.youkuaiyun.com/wslixb/article/details/53021460

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本文详细解析了Chromium浏览器中从用户点击右键保存链接到完成文件下载的整个过程。涉及核心组件包括ContextMenuHelper、DownloadController及DownloadManagerImpl等。

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Y:\chromium_org\src\chrome\android\java\src\org\chromium\chrome\browser\contextmenu\ChromeContextMenuPopulator.java

public booleanonItemSelected(ContextMenuHelper helper, ContextMenuParams params, int itemId){

……

} else if (itemId == R.id.contextmenu_save_image){

ContextMenuUma.record(params, ContextMenuUma.ACTION_SAVE_IMAGE);

if (mDelegate.startDownload(params.getSrcUrl(), false)) {

helper.startContextMenuDownload(

false,mDelegate.isDataReductionProxyEnabledForURL(params.getSrcUrl()));

}

} else if (itemId == R.id.contextmenu_save_video) {

ContextMenuUma.record(params, ContextMenuUma.ACTION_SAVE_VIDEO);

if (mDelegate.startDownload(params.getSrcUrl(), false)) {

helper.startContextMenuDownload(false,false);

}

} else if (itemId == R.id.contextmenu_save_link_as) {

ContextMenuUma.record(params, ContextMenuUma.ACTION_SAVE_LINK);

String url =params.getUnfilteredLinkUrl();

if (mDelegate.startDownload(url, true)) {

ContextMenuUma.recordSaveLinkTypes(url);

helper.startContextMenuDownload(true,false);

}

…..

}

Y:\chromium_org\src\chrome\android\java\src\org\chromium\chrome\browser\contextmenu\ContextMenuHelper.java

publicvoid startContextMenuDownload(boolean isLink,boolean isDataReductionProxyEnabled) {

privatenative void nativeOnStartDownload(

long nativeContextMenuHelper,boolean isLink, boolean isDataReductionProxyEnabled);

X:\SmartGit_trunk_2.0\chromium_2125\android_packages_apps_Browser_chromium\src\chrome\browser\ui\android\context_menu_helper.cc

voidContextMenuHelper::OnStartDownload(

JNIEnv* env,

const JavaParamRef<jobject>& obj,

jboolean jis_link,

jboolean jis_data_reduction_proxy_enabled)

Y:\chromium_org\src\chrome\browser\android\download\download_controller.cc

voidDownloadController::StartContextMenuDownload(

const ContextMenuParams& params,WebContents* web_contents, bool is_link,

const std::string& extra_headers)

void CreateContextMenuDownload(int render_process_id,

intrender_view_id,

constcontent::ContextMenuParams& params,

bool is_link,

conststd::string& extra_headers,

bool granted)

{

……

if (!is_link &&extra_headers.empty())

dl_params->set_prefer_cache(true);

dl_params->set_prompt(false);

dlm->DownloadUrl(std::move(dl_params));

……

}

/chromium_new/src/content/browser/download/download_manager_impl.cc

voidDownloadManagerImpl::DownloadUrl(

std::unique_ptr<DownloadUrlParameters> params){

……

BrowserThread::PostTaskAndReplyWithResult(

BrowserThread::IO,FROM_HERE,

base::Bind(&BeginDownload, base::Passed(&params),

browser_context_->GetResourceContext(),

content::DownloadItem::kInvalidId, weak_factory_.GetWeakPtr()),

base::Bind(&DownloadManagerImpl::AddUrlDownloader,

weak_factory_.GetWeakPtr()));

……

}

std::unique_ptr<UrlDownloader,BrowserThread::DeleteOnIOThread> BeginDownload(

std::unique_ptr<DownloadUrlParameters>params,

content::ResourceContext* resource_context,

uint32_t download_id,

base::WeakPtr<DownloadManagerImpl> download_manager){

/chromium_new/src/content/browser/loader/resource_dispatcher_host_impl.cc

DownloadInterruptReasonResourceDispatcherHostImpl::BeginDownload(

std::unique_ptr<net::URLRequest>request,

const Referrer& referrer,

bool is_content_initiated,

ResourceContext* context,

int render_process_id,

int render_view_route_id,

int render_frame_route_id,

bool do_not_prompt_for_login)

ResourceDispatcherHostImpl::CreateResourceHandlerForDownload(

net::URLRequest* request,

bool is_content_initiated,

bool must_download)

voidResourceDispatcherHostImpl::BeginRequestInternal(

std::unique_ptr<net::URLRequest>request,

std::unique_ptr<ResourceHandler> handler)

/chromium_2125_2.0/src/content/browser/download/download_resource_handler.cc

boolDownloadResourceHandler::OnResponseStarted(

ResourceResponse* response,

bool* defer)

staticvoid StartOnUIThread(

scoped_ptr<DownloadCreateInfo> info,

DownloadResourceHandler::DownloadTabInfo*tab_info,

scoped_ptr<ByteStreamReader> stream,

const DownloadUrlParameters::OnStartedCallback& started_cb)

/chromium_2125_2.0/src/content/browser/download/download_manager_impl.cc

voidDownloadManagerImpl::StartDownload(

scoped_ptr<DownloadCreateInfo> info,

scoped_ptr<ByteStreamReader> stream,

const DownloadUrlParameters::OnStartedCallback& on_started)

voidDownloadManagerImpl::StartDownloadWithId(

scoped_ptr<DownloadCreateInfo> info,

scoped_ptr<ByteStreamReader> stream,

constDownloadUrlParameters::OnStartedCallback& on_started,

bool new_download,

uint32 id){

……

base::FilePath default_download_directory;

if (delegate_) {

base::FilePath website_save_directory; // Unused

bool skip_dir_check = false; // Unused

delegate_->GetSaveDir(GetBrowserContext(),&website_save_directory,

&default_download_directory,&skip_dir_check);

}

……

download->Start(download_file.Pass(),req_handle.Pass());

……

}

/chromium_2125_2.0/src/content/browser/download/download_item_impl.cc

voidDownloadItemImpl::Start(

scoped_ptr<DownloadFile> file,

scoped_ptr<DownloadRequestHandleInterface> req_handle)

void DownloadItemImpl::OnDownloadFileInitialized(

DownloadInterruptReason result)

voidDownloadItemImpl::OnDownloadTargetDetermined(

const base::FilePath& target_path,

TargetDisposition disposition,

DownloadDangerType danger_type,

const base::FilePath& intermediate_path)

voidDownloadItemImpl::OnDownloadRenamedToIntermediateName(

DownloadInterruptReason reason,

const base::FilePath& full_path)

delegate上层需要设置

/chromium_2125_2.0/src/chrome/browser/download/

chrome_download_manager_delegate.cc