/** Calculate the minimum and preferred size for every row and column. */
private void calculateSizes() {
Dimension dim[] = new Dimension[child.size()];
for (int i = 0; i < dim.length; i++) dim[i] = child.get(i).widget.getMinimumSize();
minRowSize = calculateRequiredSizes(dim, true);
minColSize = calculateRequiredSizes(dim, false);
for (int i = 0; i < dim.length; i++) {
ChildInfo info = child.get(i);
LayoutInfo layout = (info.layout == null ? defaultLayout : info.layout);
dim[i] = layout.getPreferredSize(info.widget);
}
prefRowSize = calculateRequiredSizes(dim, true);
prefColSize = calculateRequiredSizes(dim, false);
}
/**
* Remove a child Widget from this container.
*
* @param index the index of the Widget to remove
*/
public void remove(int index) {
Widget w = child.get(index).widget;
getComponent().remove(w.getComponent());
child.remove(index);
removeAsParent(w);
invalidateSize();
}
/**
* Set the range of cells occupied by a Widget.
*
* @param index the index of the Widget for which to set the cells
* @param cells a Rectangle specifying the range of rows and columns to be occupied by the Widget
*/
public void setChildCells(int index, Rectangle cells) {
ChildInfo info = child.get(index);
info.x = cells.x;
info.y = cells.y;
info.width = cells.width;
info.height = cells.height;
invalidateSize();
}
/**
* Calculate the minimum or preferred size of every row or column.
*
* @param dim the minimum or preferred size of every child
* @param row true if row sizes should be calculated, false if column sizes should be calculated
* @return the size required for every row or column
*/
private int[] calculateRequiredSizes(Dimension dim[], boolean row) {
// Build a linked list of size requirements of every child.
LinkedList<int[]> requiredList = new LinkedList<int[]>();
for (int i = 0; i < dim.length; i++) {
ChildInfo info = child.get(i);
if (row) requiredList.addLast(new int[] {info.y, info.height, dim[i].height});
else requiredList.addLast(new int[] {info.x, info.width, dim[i].width});
}
// Find the required size for each row or column.
int width[] = new int[row ? rowWeight.length : colWeight.length];
double weight[] = (row ? rowWeight : colWeight);
for (int currentWidth = 1; requiredList.size() > 0; currentWidth++) {
// Apply constraints for all children which occupy currentWidth rows or columns.
Iterator<int[]> iter = requiredList.iterator();
while (iter.hasNext()) {
int req[] = iter.next();
if (req[1] != currentWidth) continue;
iter.remove();
if (currentWidth == 1) {
width[req[0]] = Math.max(width[req[0]], req[2]);
continue;
}
// Find how much space is currently available.
int total = 0;
for (int i = 0; i < currentWidth; i++) total += width[req[0] + i];
if (total >= req[2]) continue; // It is already wide enough.
// Allocate additional space to the rows or columns, based on their weights.
double totalWeight = 0.0;
for (int i = 0; i < currentWidth; i++) totalWeight += weight[req[0] + i];
int extra[] = new int[currentWidth];
int totalExtra = 0;
for (int i = 0; i < currentWidth - 1; i++) {
double w = (totalWeight > 0.0 ? weight[req[0] + i] / totalWeight : 1.0 / currentWidth);
extra[i] += w * (req[2] - total);
totalExtra += extra[i];
}
extra[extra.length - 1] = req[2] - total - totalExtra;
for (int i = 0; i < currentWidth; i++) width[req[0] + i] += extra[i];
}
}
return width;
}
/**
* Set the number of columns in this FormContainer. If this increases the number of columns, the
* new columns will have weights of 1.0 by default. If this decreases the number of columns, any
* child Widgets that extend beyond the last column will be removed.
*/
public void setColumnCount(int columns) {
double newWeight[] = new double[columns];
if (columns > colWeight.length) {
for (int i = 0; i < colWeight.length; i++) newWeight[i] = colWeight[i];
for (int i = colWeight.length; i < newWeight.length; i++) newWeight[i] = 1.0;
} else {
for (int i = child.size() - 1; i >= 0; i--) {
ChildInfo info = child.get(i);
if (info.x + info.width > columns) remove(i);
}
for (int i = 0; i < newWeight.length; i++) newWeight[i] = colWeight[i];
}
colWeight = newWeight;
}
/**
* Set the number of rows in this FormContainer. If this increases the number of rows, the new
* rows will have weights of 1.0 by default. If this decreases the number of rows, any child
* Widgets that extend beyond the last row will be removed.
*/
public void setRowCount(int rows) {
double newWeight[] = new double[rows];
if (rows > rowWeight.length) {
for (int i = 0; i < rowWeight.length; i++) newWeight[i] = rowWeight[i];
for (int i = rowWeight.length; i < newWeight.length; i++) newWeight[i] = 1.0;
} else {
for (int i = child.size() - 1; i >= 0; i--) {
ChildInfo info = child.get(i);
if (info.y + info.height > rows) remove(i);
}
for (int i = 0; i < newWeight.length; i++) newWeight[i] = rowWeight[i];
}
rowWeight = newWeight;
}
/**
* Layout the child Widgets. This may be invoked whenever something has changed (the size of this
* WidgetContainer, the preferred size of one of its children, etc.) that causes the layout to no
* longer be correct. If a child is itself a WidgetContainer, its layoutChildren() method will be
* called in turn.
*/
public void layoutChildren() {
if (minColSize == null) calculateSizes();
Dimension size = getComponent().getSize();
int rowPos[] = calculatePositions(minRowSize, prefRowSize, rowWeight, size.height);
int colPos[] = calculatePositions(minColSize, prefColSize, colWeight, size.width);
Rectangle cell = new Rectangle();
for (int i = 0; i < child.size(); i++) {
ChildInfo info = child.get(i);
LayoutInfo layout = (info.layout == null ? defaultLayout : info.layout);
cell.x = (info.x == 0 ? 0 : colPos[info.x - 1]);
cell.y = (info.y == 0 ? 0 : rowPos[info.y - 1]);
cell.width = colPos[info.x + info.width - 1] - cell.x;
cell.height = rowPos[info.y + info.height - 1] - cell.y;
info.widget.getComponent().setBounds(layout.getWidgetLayout(info.widget, cell));
if (info.widget instanceof WidgetContainer) ((WidgetContainer) info.widget).layoutChildren();
}
}
/** Get a Collection containing all child Widgets of this container. */
public Collection<Widget> getChildren() {
ArrayList<Widget> list = new ArrayList<Widget>(child.size());
for (int i = 0; i < child.size(); i++) list.add(child.get(i).widget);
return list;
}
/** Get the i'th child of this container. */
public Widget getChild(int i) {
return child.get(i).widget;
}
/**
* Get the index of a particular Widget.
*
* @param widget the Widget to locate
* @return the position of the Widget within this container
*/
public int getWidgetIndex(Widget widget) {
for (int i = 0; i < child.size(); i++) if (child.get(i).widget == widget) return i;
return -1;
}
/** Remove all child Widgets from this container. */
public void removeAll() {
getComponent().removeAll();
for (int i = 0; i < child.size(); i++) removeAsParent(child.get(i).widget);
child.clear();
invalidateSize();
}
/**
* Get the range of cells occupied by a Widget.
*
* @param index the index of the Widget for which to get the cells
* @return a Rectangle specifying the range of rows and columns occupied by the Widget
*/
public Rectangle getChildCells(int index) {
ChildInfo info = child.get(index);
return new Rectangle(info.x, info.y, info.width, info.height);
}
/**
* Set the LayoutInfo for a particular Widget.
*
* @param widget the Widget for which to set the LayoutInfo
* @param layout the new LayoutInfo. If null, the default LayoutInfo will be used
*/
public void setChildLayout(Widget widget, LayoutInfo layout) {
int index = getWidgetIndex(widget);
if (index == -1) return;
child.get(index).layout = layout;
invalidateSize();
}
/**
* Get the LayoutInfo for a particular Widget.
*
* @param widget the Widget for which to get the LayoutInfo
* @return the LayoutInfo being used for that Widget. This may return null, which indicates that
* the default LayoutInfo is being used. It will also return null if the specified Widget is
* not a child of this container.
*/
public LayoutInfo getChildLayout(Widget widget) {
int index = getWidgetIndex(widget);
if (index == -1) return null;
return child.get(index).layout;
}
/**
* Set the LayoutInfo for a particular Widget.
*
* @param index the index of the Widget for which to set the LayoutInfo
* @param layout the new LayoutInfo. If null, the default LayoutInfo will be used
*/
public void setChildLayout(int index, LayoutInfo layout) {
child.get(index).layout = layout;
invalidateSize();
}
/**
* Get the LayoutInfo for a particular Widget.
*
* @param index the index of the Widget for which to get the LayoutInfo
* @return the LayoutInfo being used for that Widget. This may return null, which indicates that
* the default LayoutInfo is being used.
*/
public LayoutInfo getChildLayout(int index) {
return child.get(index).layout;
}