/*
* Copyright 1999-2005 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: ListBlockLayoutManager.java 370494 2006-01-19 15:10:14Z jeremias $ */
package org.apache.fop.layoutmgr.list;
import org.apache.fop.fo.flow.ListBlock;
import org.apache.fop.layoutmgr.BlockLevelLayoutManager;
import org.apache.fop.layoutmgr.BlockStackingLayoutManager;
import org.apache.fop.layoutmgr.ConditionalElementListener;
import org.apache.fop.layoutmgr.LayoutManager;
import org.apache.fop.layoutmgr.LayoutContext;
import org.apache.fop.layoutmgr.PositionIterator;
import org.apache.fop.layoutmgr.Position;
import org.apache.fop.layoutmgr.NonLeafPosition;
import org.apache.fop.layoutmgr.RelSide;
import org.apache.fop.layoutmgr.TraitSetter;
import org.apache.fop.area.Area;
import org.apache.fop.area.Block;
import org.apache.fop.traits.MinOptMax;
import org.apache.fop.traits.SpaceVal;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
/**
* LayoutManager for a list-block FO.
* A list block contains list items which are stacked within
* the list block area..
*/
public class ListBlockLayoutManager extends BlockStackingLayoutManager
implements ConditionalElementListener {
private Block curBlockArea;
private boolean discardBorderBefore;
private boolean discardBorderAfter;
private boolean discardPaddingBefore;
private boolean discardPaddingAfter;
private MinOptMax effSpaceBefore;
private MinOptMax effSpaceAfter;
private static class StackingIter extends PositionIterator {
StackingIter(Iterator parentIter) {
super(parentIter);
}
protected LayoutManager getLM(Object nextObj) {
return ((Position) nextObj).getLM();
}
protected Position getPos(Object nextObj) {
return ((Position) nextObj);
}
}
/*
private class SectionPosition extends LeafPosition {
protected List list;
protected SectionPosition(LayoutManager lm, int pos, List l) {
super(lm, pos);
list = l;
}
}*/
/**
* Create a new list block layout manager.
* @param node list-block to create the layout manager for
*/
public ListBlockLayoutManager(ListBlock node) {
super(node);
}
/**
* Convenience method.
* @return the ListBlock node
*/
protected ListBlock getListBlockFO() {
return (ListBlock)fobj;
}
/** @see org.apache.fop.layoutmgr.LayoutManager#initialize() */
public void initialize() {
foSpaceBefore = new SpaceVal(
getListBlockFO().getCommonMarginBlock().spaceBefore, this).getSpace();
foSpaceAfter = new SpaceVal(
getListBlockFO().getCommonMarginBlock().spaceAfter, this).getSpace();
startIndent = getListBlockFO().getCommonMarginBlock().startIndent.getValue(this);
endIndent = getListBlockFO().getCommonMarginBlock().endIndent.getValue(this);
}
private void resetSpaces() {
this.discardBorderBefore = false;
this.discardBorderAfter = false;
this.discardPaddingBefore = false;
this.discardPaddingAfter = false;
this.effSpaceBefore = null;
this.effSpaceAfter = null;
}
/** @see org.apache.fop.layoutmgr.BlockStackingLayoutManager */
public LinkedList getNextKnuthElements(LayoutContext context, int alignment) {
resetSpaces();
return super.getNextKnuthElements(context, alignment);
}
/** @see org.apache.fop.layoutmgr.LayoutManager#getChangedKnuthElements(java.util.List, int) */
public LinkedList getChangedKnuthElements(List oldList, int alignment) {
//log.debug("LBLM.getChangedKnuthElements>");
return super.getChangedKnuthElements(oldList, alignment);
}
/**
* The table area is a reference area that contains areas for
* columns, bodies, rows and the contents are in cells.
*
* @param parentIter the position iterator
* @param layoutContext the layout context for adding areas
*/
public void addAreas(PositionIterator parentIter,
LayoutContext layoutContext) {
getParentArea(null);
// if this will create the first block area in a page
// and display-align is after or center, add space before
if (layoutContext.getSpaceBefore() > 0) {
addBlockSpacing(0.0, new MinOptMax(layoutContext.getSpaceBefore()));
}
getPSLM().addIDToPage(getListBlockFO().getId());
// the list block contains areas stacked from each list item
LayoutManager childLM = null;
LayoutContext lc = new LayoutContext(0);
LayoutManager firstLM = null;
LayoutManager lastLM = null;
Position firstPos = null;
Position lastPos = null;
// "unwrap" the NonLeafPositions stored in parentIter
// and put them in a new list;
LinkedList positionList = new LinkedList();
Position pos;
while (parentIter.hasNext()) {
pos = (Position)parentIter.next();
if (pos.getIndex() >= 0) {
if (firstPos == null) {
firstPos = pos;
}
lastPos = pos;
}
if (pos instanceof NonLeafPosition
&& (pos.getPosition() != null)
&& ((NonLeafPosition) pos).getPosition().getLM() != this) {
// pos was created by a child of this ListBlockLM
positionList.add(((NonLeafPosition) pos).getPosition());
lastLM = ((NonLeafPosition) pos).getPosition().getLM();
if (firstLM == null) {
firstLM = lastLM;
}
}
}
if (markers != null) {
getCurrentPV().addMarkers(markers, true, isFirst(firstPos), isLast(lastPos));
}
StackingIter childPosIter = new StackingIter(positionList.listIterator());
while ((childLM = childPosIter.getNextChildLM()) != null) {
// Add the block areas to Area
// set the space adjustment ratio
lc.setSpaceAdjust(layoutContext.getSpaceAdjust());
lc.setFlags(LayoutContext.FIRST_AREA, childLM == firstLM);
lc.setFlags(LayoutContext.LAST_AREA, childLM == lastLM);
lc.setStackLimit(layoutContext.getStackLimit());
childLM.addAreas(childPosIter, lc);
}
if (markers != null) {
getCurrentPV().addMarkers(markers, false, isFirst(firstPos), isLast(lastPos));
}
// We are done with this area add the background
TraitSetter.addBackground(curBlockArea,
getListBlockFO().getCommonBorderPaddingBackground(),
this);
TraitSetter.addSpaceBeforeAfter(curBlockArea, layoutContext.getSpaceAdjust(),
effSpaceBefore, effSpaceAfter);
flush();
curBlockArea = null;
resetSpaces();
}
/**
* Return an Area which can contain the passed childArea. The childArea
* may not yet have any content, but it has essential traits set.
* In general, if the LayoutManager already has an Area it simply returns
* it. Otherwise, it makes a new Area of the appropriate class.
* It gets a parent area for its area by calling its parent LM.
* Finally, based on the dimensions of the parent area, it initializes
* its own area. This includes setting the content IPD and the maximum
* BPD.
*
* @param childArea the child area
* @return the parent area of the child
*/
public Area getParentArea(Area childArea) {
if (curBlockArea == null) {
curBlockArea = new Block();
// Set up dimensions
// Must get dimensions from parent area
/*Area parentArea =*/ parentLM.getParentArea(curBlockArea);
// set traits
TraitSetter.setProducerID(curBlockArea, getListBlockFO().getId());
TraitSetter.addBorders(curBlockArea,
getListBlockFO().getCommonBorderPaddingBackground(),
discardBorderBefore, discardBorderAfter, false, false, this);
TraitSetter.addPadding(curBlockArea,
getListBlockFO().getCommonBorderPaddingBackground(),
discardPaddingBefore, discardPaddingAfter, false, false, this);
TraitSetter.addMargins(curBlockArea,
getListBlockFO().getCommonBorderPaddingBackground(),
getListBlockFO().getCommonMarginBlock(),
this);
TraitSetter.addBreaks(curBlockArea,
getListBlockFO().getBreakBefore(),
getListBlockFO().getBreakAfter());
int contentIPD = referenceIPD - getIPIndents();
curBlockArea.setIPD(contentIPD);
setCurrentArea(curBlockArea);
}
return curBlockArea;
}
/**
* Add the child area to this layout manager.
*
* @param childArea the child area to add
*/
public void addChildArea(Area childArea) {
if (curBlockArea != null) {
curBlockArea.addBlock((Block) childArea);
}
}
/**
* Reset the position of this layout manager.
*
* @param resetPos the position to reset to
*/
public void resetPosition(Position resetPos) {
if (resetPos == null) {
reset(null);
} else {
//TODO Something to put here?
}
}
/** @see org.apache.fop.layoutmgr.BlockLevelLayoutManager#mustKeepTogether() */
public boolean mustKeepTogether() {
//TODO Keeps will have to be more sophisticated sooner or later
return ((BlockLevelLayoutManager)getParent()).mustKeepTogether()
|| !getListBlockFO().getKeepTogether().getWithinPage().isAuto()
|| !getListBlockFO().getKeepTogether().getWithinColumn().isAuto();
}
/** @see org.apache.fop.layoutmgr.BlockLevelLayoutManager#mustKeepWithPrevious() */
public boolean mustKeepWithPrevious() {
return !getListBlockFO().getKeepWithPrevious().getWithinPage().isAuto()
|| !getListBlockFO().getKeepWithPrevious().getWithinColumn().isAuto();
}
/** @see org.apache.fop.layoutmgr.BlockLevelLayoutManager#mustKeepWithNext() */
public boolean mustKeepWithNext() {
return !getListBlockFO().getKeepWithNext().getWithinPage().isAuto()
|| !getListBlockFO().getKeepWithNext().getWithinColumn().isAuto();
}
/** @see org.apache.fop.layoutmgr.ConditionalElementListener */
public void notifySpace(RelSide side, MinOptMax effectiveLength) {
if (RelSide.BEFORE == side) {
if (log.isDebugEnabled()) {
log.debug(this + ": Space " + side + ", "
+ this.effSpaceBefore + "-> " + effectiveLength);
}
this.effSpaceBefore = effectiveLength;
} else {
if (log.isDebugEnabled()) {
log.debug(this + ": Space " + side + ", "
+ this.effSpaceAfter + "-> " + effectiveLength);
}
this.effSpaceAfter = effectiveLength;
}
}
/** @see org.apache.fop.layoutmgr.ConditionalElementListener */
public void notifyBorder(RelSide side, MinOptMax effectiveLength) {
if (effectiveLength == null) {
if (RelSide.BEFORE == side) {
this.discardBorderBefore = true;
} else {
this.discardBorderAfter = true;
}
}
if (log.isDebugEnabled()) {
log.debug(this + ": Border " + side + " -> " + effectiveLength);
}
}
/** @see org.apache.fop.layoutmgr.ConditionalElementListener */
public void notifyPadding(RelSide side, MinOptMax effectiveLength) {
if (effectiveLength == null) {
if (RelSide.BEFORE == side) {
this.discardPaddingBefore = true;
} else {
this.discardPaddingAfter = true;
}
}
if (log.isDebugEnabled()) {
log.debug(this + ": Padding " + side + " -> " + effectiveLength);
}
}
}