breakView
* method is called to try and carve the view into pieces
* that fit.
*
* @author Timothy Prinzing
* @author Scott Violet
* @author Igor Kushnirskiy
* @see View
*/
public class ParagraphView extends FlowView implements TabExpander {
/**
* Constructs a ParagraphView for the given element.
*
* @param elem the element that this view is responsible for
*/
public ParagraphView(Element elem) {
super(elem, View.Y_AXIS);
setPropertiesFromAttributes();
Document doc = elem.getDocument();
Object i18nFlag = doc.getProperty(AbstractDocument.I18NProperty);
if ((i18nFlag != null) && i18nFlag.equals(Boolean.TRUE)) {
try {
if (i18nStrategy == null) {
// the classname should probably come from a property file.
String classname = "javax.swing.text.TextLayoutStrategy";
ClassLoader loader = getClass().getClassLoader();
if (loader != null) {
i18nStrategy = loader.loadClass(classname);
} else {
i18nStrategy = Class.forName(classname);
}
}
Object o = i18nStrategy.newInstance();
if (o instanceof FlowStrategy) {
strategy = (FlowStrategy) o;
}
} catch (Throwable e) {
throw new StateInvariantError("ParagraphView: Can't create i18n strategy: "
+ e.getMessage());
}
}
}
/**
* Sets the type of justification.
*
* @param j one of the following values:
* StyleConstants.ALIGN_LEFT
* StyleConstants.ALIGN_CENTER
* StyleConstants.ALIGN_RIGHT
* Views
* that represent the child elements. This is the number
* of views that have been tiled in two dimensions,
* and should be equivalent to the number of child elements
* to the element this view is responsible for.
*
* @return the number of views that this ParagraphView
* is responsible for
*/
protected int getLayoutViewCount() {
return layoutPool.getViewCount();
}
/**
* Returns the view at a given index.
* The child views of the paragraph are rows which
* have been used to arrange pieces of the Views
* that represent the child elements. This methods returns
* the view responsible for the child element index
* (prior to breaking). These are the Views that were
* produced from a factory (to represent the child
* elements) and used for layout.
*
* @param index the index of the desired view
* @return the view at index
*/
protected View getLayoutView(int index) {
return layoutPool.getView(index);
}
/**
* Returns the next visual position for the cursor, in
* either the east or west direction.
* Overridden from CompositeView.
* @param pos position into the model
* @param b either Position.Bias.Forward or
* Position.Bias.Backward
* @param a the allocated region to render into
* @param direction either SwingConstants.NORTH
* or SwingConstants.SOUTH
* @param biasRet an array containing the bias that were checked
* in this method
* @return the location in the model that represents the
* next location visual position
*/
protected int getNextNorthSouthVisualPositionFrom(int pos, Position.Bias b,
Shape a, int direction,
Position.Bias[] biasRet)
throws BadLocationException {
int vIndex;
if(pos == -1) {
vIndex = (direction == NORTH) ?
getViewCount() - 1 : 0;
}
else {
if(b == Position.Bias.Backward && pos > 0) {
vIndex = getViewIndexAtPosition(pos - 1);
}
else {
vIndex = getViewIndexAtPosition(pos);
}
if(direction == NORTH) {
if(vIndex == 0) {
return -1;
}
vIndex--;
}
else if(++vIndex >= getViewCount()) {
return -1;
}
}
// vIndex gives index of row to look in.
JTextComponent text = (JTextComponent)getContainer();
Caret c = text.getCaret();
Point magicPoint;
magicPoint = (c != null) ? c.getMagicCaretPosition() : null;
int x;
if(magicPoint == null) {
Shape posBounds;
try {
posBounds = text.getUI().modelToView(text, pos, b);
} catch (BadLocationException exc) {
posBounds = null;
}
if(posBounds == null) {
x = 0;
}
else {
x = posBounds.getBounds().x;
}
}
else {
x = magicPoint.x;
}
return getClosestPositionTo(pos, b, a, direction, biasRet, vIndex, x);
}
/**
* Returns the closest model position to x.
* rowIndex gives the index of the view that corresponds
* that should be looked in.
* @param pos position into the model
* @param a the allocated region to render into
* @param direction one of the following values:
* SwingConstants.NORTH
* SwingConstants.SOUTH
* x
*/
// NOTE: This will not properly work if ParagraphView contains
// other ParagraphViews. It won't raise, but this does not message
// the children views with getNextVisualPositionFrom.
protected int getClosestPositionTo(int pos, Position.Bias b, Shape a,
int direction, Position.Bias[] biasRet,
int rowIndex, int x)
throws BadLocationException {
JTextComponent text = (JTextComponent)getContainer();
Document doc = getDocument();
AbstractDocument aDoc = (doc instanceof AbstractDocument) ?
(AbstractDocument)doc : null;
View row = getView(rowIndex);
int lastPos = -1;
// This could be made better to check backward positions too.
biasRet[0] = Position.Bias.Forward;
for(int vc = 0, numViews = row.getViewCount(); vc < numViews; vc++) {
View v = row.getView(vc);
int start = v.getStartOffset();
boolean ltr = (aDoc != null) ? aDoc.isLeftToRight
(start, start + 1) : true;
if(ltr) {
lastPos = start;
for(int end = v.getEndOffset(); lastPos < end; lastPos++) {
float xx = text.modelToView(lastPos).getBounds().x;
if(xx >= x) {
while (++lastPos < end &&
text.modelToView(lastPos).getBounds().x == xx) {
}
return --lastPos;
}
}
lastPos--;
}
else {
for(lastPos = v.getEndOffset() - 1; lastPos >= start;
lastPos--) {
float xx = text.modelToView(lastPos).getBounds().x;
if(xx >= x) {
while (--lastPos >= start &&
text.modelToView(lastPos).getBounds().x == xx) {
}
return ++lastPos;
}
}
lastPos++;
}
}
if(lastPos == -1) {
return getStartOffset();
}
return lastPos;
}
/**
* Determines in which direction the next view lays.
* Consider the View at index n.
* Typically the Views are layed out
* from left to right, so that the View
* to the EAST will be at index n + 1, and the
* View to the WEST will be at index n - 1.
* In certain situations, such as with bidirectional text,
* it is possible that the View to EAST is not
* at index n + 1, but rather at index n - 1,
* or that the View to the WEST is not at
* index n - 1, but index n + 1. In this case this method
* would return true, indicating the Views are
* layed out in descending order.
*
* This will return true if the text is layed out right
* to left at position, otherwise false.
*
* @param position position into the model
* @param bias either Position.Bias.Forward or
* Position.Bias.Backward
* @return true if the text is layed out right to left at
* position, otherwise false.
*/
protected boolean flipEastAndWestAtEnds(int position,
Position.Bias bias) {
Document doc = getDocument();
if(doc instanceof AbstractDocument &&
!((AbstractDocument)doc).isLeftToRight(getStartOffset(),
getStartOffset() + 1)) {
return true;
}
return false;
}
// --- FlowView methods ---------------------------------------------
/**
* Fetches the constraining span to flow against for
* the given child index.
* @param index the index of the view being queried
* @return the constraining span for the given view at
* index
* @since 1.3
*/
public int getFlowSpan(int index) {
View child = getView(index);
int adjust = 0;
if (child instanceof Row) {
Row row = (Row) child;
adjust = row.getLeftInset() + row.getRightInset();
}
return (layoutSpan == Integer.MAX_VALUE) ? layoutSpan
: (layoutSpan - adjust);
}
/**
* Fetches the location along the flow axis that the
* flow span will start at.
* @param index the index of the view being queried
* @return the location for the given view at
* index
* @since 1.3
*/
public int getFlowStart(int index) {
View child = getView(index);
int adjust = 0;
if (child instanceof Row) {
Row row = (Row) child;
adjust = row.getLeftInset();
}
return tabBase + adjust;
}
/**
* Create a View that should be used to hold a
* a row's worth of children in a flow.
* @return the new View
* @since 1.3
*/
protected View createRow() {
return new Row(getElement());
}
// --- TabExpander methods ------------------------------------------
/**
* Returns the next tab stop position given a reference position.
* This view implements the tab coordinate system, and calls
* getTabbedSpan on the logical children in the process
* of layout to determine the desired span of the children. The
* logical children can delegate their tab expansion upward to
* the paragraph which knows how to expand tabs.
* LabelView is an example of a view that delegates
* its tab expansion needs upward to the paragraph.
*
* This is implemented to try and locate a TabSet
* in the paragraph element's attribute set. If one can be
* found, its settings will be used, otherwise a default expansion
* will be provided. The base location for for tab expansion
* is the left inset from the paragraphs most recent allocation
* (which is what the layout of the children is based upon).
*
* @param x the X reference position
* @param tabOffset the position within the text stream
* that the tab occurred at >= 0
* @return the trailing end of the tab expansion >= 0
* @see TabSet
* @see TabStop
* @see LabelView
*/
public float nextTabStop(float x, int tabOffset) {
// If the text isn't left justified, offset by 10 pixels!
if(justification != StyleConstants.ALIGN_LEFT)
return x + 10.0f;
x -= tabBase;
TabSet tabs = getTabSet();
if(tabs == null) {
// a tab every 72 pixels.
return (float)(tabBase + (((int)x / 72 + 1) * 72));
}
TabStop tab = tabs.getTabAfter(x + .01f);
if(tab == null) {
// no tab, do a default of 5 pixels.
// Should this cause a wrapping of the line?
return tabBase + x + 5.0f;
}
int alignment = tab.getAlignment();
int offset;
switch(alignment) {
default:
case TabStop.ALIGN_LEFT:
// Simple case, left tab.
return tabBase + tab.getPosition();
case TabStop.ALIGN_BAR:
// PENDING: what does this mean?
return tabBase + tab.getPosition();
case TabStop.ALIGN_RIGHT:
case TabStop.ALIGN_CENTER:
offset = findOffsetToCharactersInString(tabChars,
tabOffset + 1);
break;
case TabStop.ALIGN_DECIMAL:
offset = findOffsetToCharactersInString(tabDecimalChars,
tabOffset + 1);
break;
}
if (offset == -1) {
offset = getEndOffset();
}
float charsSize = getPartialSize(tabOffset + 1, offset);
switch(alignment) {
case TabStop.ALIGN_RIGHT:
case TabStop.ALIGN_DECIMAL:
// right and decimal are treated the same way, the new
// position will be the location of the tab less the
// partialSize.
return tabBase + Math.max(x, tab.getPosition() - charsSize);
case TabStop.ALIGN_CENTER:
// Similar to right, but half the partialSize.
return tabBase + Math.max(x, tab.getPosition() - charsSize / 2.0f);
}
// will never get here!
return x;
}
/**
* Gets the Tabset to be used in calculating tabs.
*
* @return the TabSet
*/
protected TabSet getTabSet() {
return StyleConstants.getTabSet(getElement().getAttributes());
}
/**
* Returns the size used by the views between
* startOffset and endOffset.
* This uses getPartialView to calculate the
* size if the child view implements the
* TabableView interface. If a
* size is needed and a View does not implement
* the TabableView interface,
* the preferredSpan will be used.
*
* @param startOffset the starting document offset >= 0
* @param endOffset the ending document offset >= startOffset
* @return the size >= 0
*/
protected float getPartialSize(int startOffset, int endOffset) {
float size = 0.0f;
int viewIndex;
int numViews = getViewCount();
View view;
int viewEnd;
int tempEnd;
// Have to search layoutPool!
// PENDING: when ParagraphView supports breaking location
// into layoutPool will have to change!
viewIndex = getElement().getElementIndex(startOffset);
numViews = layoutPool.getViewCount();
while(startOffset < endOffset && viewIndex < numViews) {
view = layoutPool.getView(viewIndex++);
viewEnd = view.getEndOffset();
tempEnd = Math.min(endOffset, viewEnd);
if(view instanceof TabableView)
size += ((TabableView)view).getPartialSpan(startOffset, tempEnd);
else if(startOffset == view.getStartOffset() &&
tempEnd == view.getEndOffset())
size += view.getPreferredSpan(View.X_AXIS);
else
// PENDING: should we handle this better?
return 0.0f;
startOffset = viewEnd;
}
return size;
}
/**
* Finds the next character in the document with a character in
* string, starting at offset start. If
* there are no characters found, -1 will be returned.
*
* @param string the string of characters
* @param start where to start in the model >= 0
* @return the document offset, or -1 if no characters found
*/
protected int findOffsetToCharactersInString(char[] string,
int start) {
int stringLength = string.length;
int end = getEndOffset();
Segment seg = new Segment();
try {
getDocument().getText(start, end - start, seg);
} catch (BadLocationException ble) {
return -1;
}
for(int counter = seg.offset, maxCounter = seg.offset + seg.count;
counter < maxCounter; counter++) {
char currentChar = seg.array[counter];
for(int subCounter = 0; subCounter < stringLength;
subCounter++) {
if(currentChar == string[subCounter])
return counter - seg.offset + start;
}
}
// No match.
return -1;
}
/**
* Returns where the tabs are calculated from.
* @return where tabs are calculated from
*/
protected float getTabBase() {
return (float)tabBase;
}
// ---- View methods ----------------------------------------------------
/**
* Renders using the given rendering surface and area on that
* surface. This is implemented to delgate to the superclass
* after stashing the base coordinate for tab calculations.
*
* @param g the rendering surface to use
* @param a the allocated region to render into
* @see View#paint
*/
public void paint(Graphics g, Shape a) {
Rectangle alloc = (a instanceof Rectangle) ? (Rectangle)a : a.getBounds();
tabBase = alloc.x + getLeftInset();
super.paint(g, a);
// line with the negative firstLineIndent value needs
// special handling
if (firstLineIndent < 0) {
Shape sh = getChildAllocation(0, a);
if ((sh != null) && sh.intersects(alloc)) {
int x = alloc.x + getLeftInset() + firstLineIndent;
int y = alloc.y + getTopInset();
Rectangle clip = g.getClipBounds();
tempRect.x = x + getOffset(X_AXIS, 0);
tempRect.y = y + getOffset(Y_AXIS, 0);
tempRect.width = getSpan(X_AXIS, 0) - firstLineIndent;
tempRect.height = getSpan(Y_AXIS, 0);
if (tempRect.intersects(clip)) {
tempRect.x = tempRect.x - firstLineIndent;
paintChild(g, tempRect, 0);
}
}
}
}
/**
* Determines the desired alignment for this view along an
* axis. This is implemented to give the alignment to the
* center of the first row along the y axis, and the default
* along the x axis.
*
* @param axis may be either View.X_AXIS or
* View.Y_AXIS
* @return the desired alignment. This should be a value
* between 0.0 and 1.0 inclusive, where 0 indicates alignment at the
* origin and 1.0 indicates alignment to the full span
* away from the origin. An alignment of 0.5 would be the
* center of the view.
*/
public float getAlignment(int axis) {
switch (axis) {
case Y_AXIS:
float a = 0.5f;
if (getViewCount() != 0) {
int paragraphSpan = (int) getPreferredSpan(View.Y_AXIS);
View v = getView(0);
int rowSpan = (int) v.getPreferredSpan(View.Y_AXIS);
a = (paragraphSpan != 0) ? ((float)(rowSpan / 2)) / paragraphSpan : 0;
}
return a;
case X_AXIS:
return 0.5f;
default:
throw new IllegalArgumentException("Invalid axis: " + axis);
}
}
/**
* Breaks this view on the given axis at the given length.
*
* ParagraphView instances are breakable
* along the Y_AXIS only, and only if
* len is after the first line.
*
* @param axis may be either View.X_AXIS
* or View.Y_AXIS
* @param len specifies where a potential break is desired
* along the given axis >= 0
* @param a the current allocation of the view
* @return the fragment of the view that represents the
* given span, if the view can be broken; if the view
* doesn't support breaking behavior, the view itself is
* returned
* @see View#breakView
*/
public View breakView(int axis, float len, Shape a) {
if(axis == View.Y_AXIS) {
if(a != null) {
Rectangle alloc = a.getBounds();
setSize(alloc.width, alloc.height);
}
// Determine what row to break on.
// PENDING(prinz) add break support
return this;
}
return this;
}
/**
* Gets the break weight for a given location.
*
* ParagraphView instances are breakable
* along the Y_AXIS only, and only if
* len is after the first row. If the length
* is less than one row, a value of BadBreakWeight
* is returned.
*
* @param axis may be either View.X_AXIS
* or View.Y_AXIS
* @param len specifies where a potential break is desired >= 0
* @return a value indicating the attractiveness of breaking here;
* either GoodBreakWeight or BadBreakWeight
* @see View#getBreakWeight
*/
public int getBreakWeight(int axis, float len) {
if(axis == View.Y_AXIS) {
// PENDING(prinz) make this return a reasonable value
// when paragraph breaking support is re-implemented.
// If less than one row, bad weight value should be
// returned.
//return GoodBreakWeight;
return BadBreakWeight;
}
return BadBreakWeight;
}
/**
* Calculate the needs for the paragraph along the minor axis.
*
*
This uses size requirements of the superclass, modified to take into * account the non-breakable areas at the adjacent views edges. The minimal * size requirements for such views should be no less than the sum of all * adjacent fragments.
* *If the {@code axis} parameter is neither {@code View.X_AXIS} nor * {@code View.Y_AXIS}, {@link IllegalArgumentException} is thrown. If the * {@code r} parameter is {@code null,} a new {@code SizeRequirements} * object is created, otherwise the supplied {@code SizeRequirements} * object is returned.
* * @param axis the minor axis * @param r the input {@code SizeRequirements} object * @return the new or adjusted {@code SizeRequirements} object * @throws IllegalArgumentException if the {@code axis} parameter is invalid */ @Override protected SizeRequirements calculateMinorAxisRequirements(int axis, SizeRequirements r) { r = super.calculateMinorAxisRequirements(axis, r); float min = 0; float glue = 0; int n = getLayoutViewCount(); for (int i = 0; i < n; i++) { View v = getLayoutView(i); float span = v.getMinimumSpan(axis); if (v.getBreakWeight(axis, 0, v.getMaximumSpan(axis)) > View.BadBreakWeight) { // find the longest non-breakable fragments at the view edges int p0 = v.getStartOffset(); int p1 = v.getEndOffset(); float start = findEdgeSpan(v, axis, p0, p0, p1); float end = findEdgeSpan(v, axis, p1, p0, p1); glue += start; min = Math.max(min, Math.max(span, glue)); glue = end; } else { // non-breakable view glue += span; min = Math.max(min, glue); } } r.minimum = Math.max(r.minimum, (int) min); r.preferred = Math.max(r.minimum, r.preferred); r.maximum = Math.max(r.preferred, r.maximum); return r; } /** * Binary search for the longest non-breakable fragment at the view edge. */ private float findEdgeSpan(View v, int axis, int fp, int p0, int p1) { int len = p1 - p0; if (len <= 1) { // further fragmentation is not possible return v.getMinimumSpan(axis); } else { int mid = p0 + len / 2; boolean startEdge = mid > fp; // initial view is breakable hence must support fragmentation View f = startEdge ? v.createFragment(fp, mid) : v.createFragment(mid, fp); boolean breakable = f.getBreakWeight( axis, 0, f.getMaximumSpan(axis)) > View.BadBreakWeight; if (breakable == startEdge) { p1 = mid; } else { p0 = mid; } return findEdgeSpan(f, axis, fp, p0, p1); } } /** * Gives notification from the document that attributes were changed * in a location that this view is responsible for. * * @param changes the change information from the * associated document * @param a the current allocation of the view * @param f the factory to use to rebuild if the view has children * @see View#changedUpdate */ public void changedUpdate(DocumentEvent changes, Shape a, ViewFactory f) { // update any property settings stored, and layout should be // recomputed setPropertiesFromAttributes(); layoutChanged(X_AXIS); layoutChanged(Y_AXIS); super.changedUpdate(changes, a, f); } // --- variables ----------------------------------------------- private int justification; private float lineSpacing; /** Indentation for the first line, from the left inset. */ protected int firstLineIndent = 0; /** * Used by the TabExpander functionality to determine * where to base the tab calculations. This is basically * the location of the left side of the paragraph. */ private int tabBase; /** * Used to create an i18n-based layout strategy */ static Class i18nStrategy; /** Used for searching for a tab. */ static char[] tabChars; /** Used for searching for a tab or decimal character. */ static char[] tabDecimalChars; static { tabChars = new char[1]; tabChars[0] = '\t'; tabDecimalChars = new char[2]; tabDecimalChars[0] = '\t'; tabDecimalChars[1] = '.'; } /** * Internally created view that has the purpose of holding * the views that represent the children of the paragraph * that have been arranged in rows. */ class Row extends BoxView { Row(Element elem) { super(elem, View.X_AXIS); } /** * This is reimplemented to do nothing since the * paragraph fills in the row with its needed * children. */ protected void loadChildren(ViewFactory f) { } /** * Fetches the attributes to use when rendering. This view * isn't directly responsible for an element so it returns * the outer classes attributes. */ public AttributeSet getAttributes() { View p = getParent(); return (p != null) ? p.getAttributes() : null; } public float getAlignment(int axis) { if (axis == View.X_AXIS) { switch (justification) { case StyleConstants.ALIGN_LEFT: return 0; case StyleConstants.ALIGN_RIGHT: return 1; case StyleConstants.ALIGN_CENTER: return 0.5f; case StyleConstants.ALIGN_JUSTIFIED: float rv = 0.5f; //if we can justifiy the content always align to //the left. if (isJustifiableDocument()) { rv = 0f; } return rv; } } return super.getAlignment(axis); } /** * Provides a mapping from the document model coordinate space * to the coordinate space of the view mapped to it. This is * implemented to let the superclass find the position along * the major axis and the allocation of the row is used * along the minor axis, so that even though the children * are different heights they all get the same caret height. * * @param pos the position to convert * @param a the allocated region to render into * @return the bounding box of the given position * @exception BadLocationException if the given position does not represent a * valid location in the associated document * @see View#modelToView */ public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException { Rectangle r = a.getBounds(); View v = getViewAtPosition(pos, r); if ((v != null) && (!v.getElement().isLeaf())) { // Don't adjust the height if the view represents a branch. return super.modelToView(pos, a, b); } r = a.getBounds(); int height = r.height; int y = r.y; Shape loc = super.modelToView(pos, a, b); r = loc.getBounds(); r.height = height; r.y = y; return r; } /** * Range represented by a row in the paragraph is only * a subset of the total range of the paragraph element. * @see View#getRange */ public int getStartOffset() { int offs = Integer.MAX_VALUE; int n = getViewCount(); for (int i = 0; i < n; i++) { View v = getView(i); offs = Math.min(offs, v.getStartOffset()); } return offs; } public int getEndOffset() { int offs = 0; int n = getViewCount(); for (int i = 0; i < n; i++) { View v = getView(i); offs = Math.max(offs, v.getEndOffset()); } return offs; } /** * Perform layout for the minor axis of the box (i.e. the * axis orthoginal to the axis that it represents). The results * of the layout should be placed in the given arrays which represent * the allocations to the children along the minor axis. ** This is implemented to do a baseline layout of the children * by calling BoxView.baselineLayout. * * @param targetSpan the total span given to the view, which * whould be used to layout the children. * @param axis the axis being layed out. * @param offsets the offsets from the origin of the view for * each of the child views. This is a return value and is * filled in by the implementation of this method. * @param spans the span of each child view. This is a return * value and is filled in by the implementation of this method. * @return the offset and span for each child view in the * offsets and spans parameters */ protected void layoutMinorAxis(int targetSpan, int axis, int[] offsets, int[] spans) { baselineLayout(targetSpan, axis, offsets, spans); } protected SizeRequirements calculateMinorAxisRequirements(int axis, SizeRequirements r) { return baselineRequirements(axis, r); } private boolean isLastRow() { View parent; return ((parent = getParent()) == null || this == parent.getView(parent.getViewCount() - 1)); } private boolean isBrokenRow() { boolean rv = false; int viewsCount = getViewCount(); if (viewsCount > 0) { View lastView = getView(viewsCount - 1); if (lastView.getBreakWeight(X_AXIS, 0, 0) >= ForcedBreakWeight) { rv = true; } } return rv; } private boolean isJustifiableDocument() { return (! Boolean.TRUE.equals(getDocument().getProperty( AbstractDocument.I18NProperty))); } /** * Whether we need to justify this {@code Row}. * At this time (jdk1.6) we support justification on for non * 18n text. * * @return {@code true} if this {@code Row} should be justified. */ private boolean isJustifyEnabled() { boolean ret = (justification == StyleConstants.ALIGN_JUSTIFIED); //no justification for i18n documents ret = ret && isJustifiableDocument(); //no justification for the last row ret = ret && ! isLastRow(); //no justification for the broken rows ret = ret && ! isBrokenRow(); return ret; } //Calls super method after setting spaceAddon to 0. //Justification should not affect MajorAxisRequirements @Override protected SizeRequirements calculateMajorAxisRequirements(int axis, SizeRequirements r) { int oldJustficationData[] = justificationData; justificationData = null; SizeRequirements ret = super.calculateMajorAxisRequirements(axis, r); if (isJustifyEnabled()) { justificationData = oldJustficationData; } return ret; } @Override protected void layoutMajorAxis(int targetSpan, int axis, int[] offsets, int[] spans) { int oldJustficationData[] = justificationData; justificationData = null; super.layoutMajorAxis(targetSpan, axis, offsets, spans); if (! isJustifyEnabled()) { return; } int currentSpan = 0; for (int span : spans) { currentSpan += span; } if (currentSpan == targetSpan) { //no need to justify return; } // we justify text by enlarging spaces by the {@code spaceAddon}. // justification is started to the right of the rightmost TAB. // leading and trailing spaces are not extendable. // // GlyphPainter1 uses // justificationData // for all painting and measurement. int extendableSpaces = 0; int startJustifiableContent = -1; int endJustifiableContent = -1; int lastLeadingSpaces = 0; int rowStartOffset = getStartOffset(); int rowEndOffset = getEndOffset(); int spaceMap[] = new int[rowEndOffset - rowStartOffset]; Arrays.fill(spaceMap, 0); for (int i = getViewCount() - 1; i >= 0 ; i--) { View view = getView(i); if (view instanceof GlyphView) { GlyphView.JustificationInfo justificationInfo = ((GlyphView) view).getJustificationInfo(rowStartOffset); final int viewStartOffset = view.getStartOffset(); final int offset = viewStartOffset - rowStartOffset; for (int j = 0; j < justificationInfo.spaceMap.length(); j++) { if (justificationInfo.spaceMap.get(j)) { spaceMap[j + offset] = 1; } } if (startJustifiableContent > 0) { if (justificationInfo.end >= 0) { extendableSpaces += justificationInfo.trailingSpaces; } else { lastLeadingSpaces += justificationInfo.trailingSpaces; } } if (justificationInfo.start >= 0) { startJustifiableContent = justificationInfo.start + viewStartOffset; extendableSpaces += lastLeadingSpaces; } if (justificationInfo.end >= 0 && endJustifiableContent < 0) { endJustifiableContent = justificationInfo.end + viewStartOffset; } extendableSpaces += justificationInfo.contentSpaces; lastLeadingSpaces = justificationInfo.leadingSpaces; if (justificationInfo.hasTab) { break; } } } if (extendableSpaces <= 0) { //there is nothing we can do to justify return; } int adjustment = (targetSpan - currentSpan); int spaceAddon = (extendableSpaces > 0) ? adjustment / extendableSpaces : 0; int spaceAddonLeftoverEnd = -1; for (int i = startJustifiableContent - rowStartOffset, leftover = adjustment - spaceAddon * extendableSpaces; leftover > 0; leftover -= spaceMap[i], i++) { spaceAddonLeftoverEnd = i; } if (spaceAddon > 0 || spaceAddonLeftoverEnd >= 0) { justificationData = (oldJustficationData != null) ? oldJustficationData : new int[END_JUSTIFIABLE + 1]; justificationData[SPACE_ADDON] = spaceAddon; justificationData[SPACE_ADDON_LEFTOVER_END] = spaceAddonLeftoverEnd; justificationData[START_JUSTIFIABLE] = startJustifiableContent - rowStartOffset; justificationData[END_JUSTIFIABLE] = endJustifiableContent - rowStartOffset; super.layoutMajorAxis(targetSpan, axis, offsets, spans); } } //for justified row we assume the maximum horizontal span //is MAX_VALUE. @Override public float getMaximumSpan(int axis) { float ret; if (View.X_AXIS == axis && isJustifyEnabled()) { ret = Float.MAX_VALUE; } else { ret = super.getMaximumSpan(axis); } return ret; } /** * Fetches the child view index representing the given position in * the model. * * @param pos the position >= 0 * @return index of the view representing the given position, or * -1 if no view represents that position */ protected int getViewIndexAtPosition(int pos) { // This is expensive, but are views are not necessarily layed // out in model order. if(pos < getStartOffset() || pos >= getEndOffset()) return -1; for(int counter = getViewCount() - 1; counter >= 0; counter--) { View v = getView(counter); if(pos >= v.getStartOffset() && pos < v.getEndOffset()) { return counter; } } return -1; } /** * Gets the left inset. * * @return the inset */ protected short getLeftInset() { View parentView; int adjustment = 0; if ((parentView = getParent()) != null) { //use firstLineIdent for the first row if (this == parentView.getView(0)) { adjustment = firstLineIndent; } } return (short)(super.getLeftInset() + adjustment); } protected short getBottomInset() { return (short)(super.getBottomInset() + ((minorRequest != null) ? minorRequest.preferred : 0) * lineSpacing); } final static int SPACE_ADDON = 0; final static int SPACE_ADDON_LEFTOVER_END = 1; final static int START_JUSTIFIABLE = 2; //this should be the last index in justificationData final static int END_JUSTIFIABLE = 3; int justificationData[] = null; } }