gecko-dev/layout/base/public/nsIReflowCommand.h
1998-06-09 04:51:44 +00:00

117 lines
3.8 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#ifndef nsIReflowCommand_h___
#define nsIReflowCommand_h___
#include "nsISupports.h"
class nsIFrame;
class nsIPresContext;
struct nsReflowMetrics;
struct nsSize;
// IID for the nsIReflowCommand interface {C3658E40-FF20-11d1-85BC-00A02468FAB6}
#define NS_IREFLOWCOMMAND_IID \
{ 0xc3658e40, 0xff20, 0x11d1, \
{0x85, 0xbc, 0x0, 0xa0, 0x24, 0x68, 0xfa, 0xb6}}
/**
* A reflow command is an object that is generated in response to a content
* model change notification. The reflow command is given to a presentation
* shell where it is queued and then dispatched by invoking the reflow
* commands's Dispatch() member function.
*
* Reflow command processing follows a path from the root frame down to the
* target frame (the frame for which the reflow command is destined). Reflow
* commands are processed by invoking the frame's Reflow() member function.
*
* @see nsIFrame#ContentAppended()
* @see nsIFrame#ContentChanged()
* @see nsIFrame#ContentDeleted()
* @see nsIFrame#ContentInserted()
* @see nsIFrame#ContentReplaced()
* @see nsIPresShell#AppendReflowCommand()
* @see nsIPresShell#ProcessReflowCommands()
*/
class nsIReflowCommand : public nsISupports {
public:
enum ReflowType {
// Reflow commands generated in response to a content insert/delete/append
// notification. The target of the reflow command is the container frame
// itself
FrameAppended,
FrameInserted,
FrameDeleted,
// This reflow command is used when a leaf node's content changes (e.g. some
// text in a text run, an image's source, etc.). The target of the reflow
// command is the frame that changed (see nsIFrame#ContentChanged() for how
// the target frame is determined).
ContentChanged,
// When an incremental reflow operation affects a next-in-flow,
// these commands are used to get the next-in-flow to update
// itself.
PullupReflow,
PushReflow,
// This command is used to see if a prev-in-flow wants to pullup
// some children from a next-in-flow that has changed because of
// an incremental reflow.
CheckPullupReflow,
// Trap door for extensions
UserDefined
};
/**
* Dispatch the reflow command.
*
* Builds a path from the target frame back to the root frame, and then
* invokes the root frame's Reflow() member function.
*
* @see nsIFrame#Reflow()
*/
NS_IMETHOD Dispatch(nsIPresContext& aPresContext,
nsReflowMetrics& aDesiredSize,
const nsSize& aMaxSize) = 0;
/**
* Get the next frame in the command processing path. Note that this removes
* the frame from the path so you must only call it once.
*/
NS_IMETHOD GetNext(nsIFrame*& aNextFrame) = 0;
/**
* Get the target of the reflow command.
*/
NS_IMETHOD GetTarget(nsIFrame*& aTargetFrame) const = 0;
/**
* Get the type of reflow command.
*/
NS_IMETHOD GetType(ReflowType& aReflowType) const = 0;
/**
* Get the child frame associated with the reflow command.
*/
NS_IMETHOD GetChildFrame(nsIFrame*& aChildFrame) const = 0;
};
#endif /* nsIReflowCommand_h___ */