123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153 |
- /*
- * $Id$
- * Copyright (C) 2002 The Apache Software Foundation. All rights reserved.
- * For details on use and redistribution please refer to the
- * LICENSE file included with these sources.
- */
-
- package org.apache.fop.layoutmgr;
-
- import org.apache.fop.apps.FOPException;
- import org.apache.fop.fo.FObj;
- import org.apache.fop.fo.properties.Constants;
- import org.apache.fop.area.*;
-
- import java.util.ArrayList;
- import java.util.List;
-
- /**
- * LayoutManager for an fo:flow object.
- * Its parent LM is the PageLayoutManager.
- * This LM is responsible for getting columns of the appropriate size
- * and filling them with block-level areas generated by its children.
- */
- public class FlowLayoutManager extends BlockStackingLayoutManager {
-
- ArrayList blockBreaks = new ArrayList();
-
- /** Array of areas currently being filled stored by area class */
- private BlockParent[] currentAreas = new BlockParent[Area.CLASS_MAX];
-
- /**
- * This is the top level layout manager.
- * It is created by the PageSequence FO.
- */
- public FlowLayoutManager(FObj fobj) {
- super(fobj);
- }
-
- public BreakPoss getNextBreakPoss(LayoutContext context) {
-
- LayoutManager curLM ; // currently active LM
- MinOptMax stackSize = new MinOptMax();
-
- while ((curLM = getChildLM()) != null) {
- if (curLM.generatesInlineAreas()) {
- // problem
- curLM.setFinished(true);
- continue;
- }
-
- // Make break positions and return page break
- // Set up a LayoutContext
- MinOptMax bpd = context.getStackLimit();
- BreakPoss bp;
-
- LayoutContext childLC = new LayoutContext(0);
- boolean breakPage = false;
- childLC.setStackLimit(MinOptMax.subtract(bpd, stackSize));
- childLC.setRefIPD(context.getRefIPD());
-
- if (!curLM.isFinished()) {
- if ((bp = curLM.getNextBreakPoss(childLC)) != null) {
- stackSize.add(bp.getStackingSize());
- blockBreaks.add(bp);
- // set stackLimit for remaining space
- childLC.setStackLimit(MinOptMax.subtract(bpd, stackSize));
-
- if (bp.isForcedBreak()) {
- breakPage = true;
- break;
- }
- }
- }
-
- // check the stack bpd and if greater than available
- // height then go to the last best break and return
- // break position
- if (stackSize.opt > context.getStackLimit().opt) {
- breakPage = true;
- }
- if (breakPage) {
- return new BreakPoss(
- new LeafPosition(this, blockBreaks.size() - 1));
- }
- }
- setFinished(true);
- if (blockBreaks.size() > 0) {
- return new BreakPoss(
- new LeafPosition(this, blockBreaks.size() - 1));
- }
- return null;
- }
-
- public void addAreas(PositionIterator parentIter, LayoutContext layoutContext) {
-
- LayoutManager childLM ;
- int iStartPos = 0;
- LayoutContext lc = new LayoutContext(0);
- while (parentIter.hasNext()) {
- LeafPosition lfp = (LeafPosition) parentIter.next();
- // Add the block areas to Area
- PositionIterator breakPosIter =
- new BreakPossPosIter(blockBreaks, iStartPos,
- lfp.getLeafPos() + 1);
- iStartPos = lfp.getLeafPos() + 1;
- while ((childLM = breakPosIter.getNextChildLM()) != null) {
- childLM.addAreas(breakPosIter, lc);
- }
- }
-
- flush();
- // clear the breaks for the page to start for the next page
- blockBreaks.clear();
- }
-
-
- /**
- * Add child area to a the correct container, depending on its
- * area class. A Flow can fill at most one area container of any class
- * at any one time. The actual work is done by BlockStackingLM.
- */
- public boolean addChild(Area childArea) {
- return addChildToArea(childArea,
- this.currentAreas[childArea.getAreaClass()]);
- }
-
- public Area getParentArea(Area childArea) {
- // Get an area from the Page
- BlockParent parentArea =
- (BlockParent) parentLM.getParentArea(childArea);
- this.currentAreas[parentArea.getAreaClass()] = parentArea;
- setCurrentArea(parentArea);
- return parentArea;
- }
-
- public void resetPosition(Position resetPos) {
- if (resetPos == null) {
- reset(null);
- }
- }
-
- /**
- * Retrieve marker is not allowed in the flow so this reports an
- * error and returns null.
- *
- * @see org.apache.fop.layoutmgr.LayoutManager
- */
- public LayoutManager retrieveMarker(String name, int pos, int boundary) {
- // error cannot retrieve markers in flow
- return null;
- }
- }
|