gecko/layout/base/nsImageLoader.h
2012-07-30 17:20:58 +03:00

83 lines
2.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* class to notify frames of background and border image loads */
#include "nsStubImageDecoderObserver.h"
class nsIFrame;
class nsIURI;
#include "imgIRequest.h"
#include "nsCOMPtr.h"
#include "nsAutoPtr.h"
/**
* Image loaders pass notifications for background and border image
* loading and animation on to the frames.
*
* Each frame's image loaders form a linked list.
*/
class nsImageLoader : public nsStubImageDecoderObserver
{
private:
nsImageLoader(nsIFrame *aFrame, PRUint32 aActions,
nsImageLoader *aNextLoader);
virtual ~nsImageLoader();
public:
/*
* Flags to specify actions that can be taken for the image at various
* times. Reflows always occur before redraws. "Decode" refers to one
* frame being available, whereas "load" refers to all the data being loaded
* from the network.
*/
enum {
ACTION_REDRAW_ON_DECODE = 0x01,
ACTION_REDRAW_ON_LOAD = 0x02,
};
static already_AddRefed<nsImageLoader>
Create(nsIFrame *aFrame, imgIRequest *aRequest,
PRUint32 aActions, nsImageLoader *aNextLoader);
NS_DECL_ISUPPORTS
// imgIDecoderObserver (override nsStubImageDecoderObserver)
NS_IMETHOD OnStartContainer(imgIRequest *aRequest, imgIContainer *aImage);
NS_IMETHOD OnStopFrame(imgIRequest *aRequest, PRUint32 aFrame);
NS_IMETHOD OnStopRequest(imgIRequest *aRequest, bool aLastPart);
NS_IMETHOD OnImageIsAnimated(imgIRequest *aRequest);
// Do not override OnDataAvailable since background images are not
// displayed incrementally; they are displayed after the entire image
// has been loaded.
// Note: Images referenced by the <img> element are displayed
// incrementally in nsImageFrame.cpp.
// imgIContainerObserver (override nsStubImageDecoderObserver)
NS_IMETHOD FrameChanged(imgIRequest *aRequest,
imgIContainer *aContainer,
const nsIntRect *aDirtyRect);
void Destroy();
imgIRequest *GetRequest() { return mRequest; }
nsImageLoader *GetNextLoader() { return mNextLoader; }
private:
nsresult Load(imgIRequest *aImage);
/* if aDamageRect is nullptr, the whole frame is redrawn. */
void DoRedraw(const nsRect* aDamageRect);
nsIFrame *mFrame;
nsCOMPtr<imgIRequest> mRequest;
PRUint32 mActions;
nsRefPtr<nsImageLoader> mNextLoader;
// This is a boolean flag indicating whether or not the current image request
// has been registered with the refresh driver.
bool mRequestRegistered;
};