//********************************************************************** // Package //********************************************************************* package org.freixas.tablelayout; //********************************************************************** // Import list //********************************************************************** import java.awt.*; import java.util.Arrays; import java.util.HashMap; import java.util.Iterator; /** * This layout was inspired by the HTML table: it lays out components * much like the HTML table lays out table data. It is as capable as * the GridBagLayout, but much easier to use. *

Attributes

*

* When you create a TableLayout, you pass in a String which defines a * set of attributes for the table. The TableLayout is then assigned * to a Container. As you add each Component to the Container, you can * also associate the Component with its own set of attributes. *

* The format of the attributes is similar to HTML attributes. The * attributes are case insensitive and can be separated with * any whitespace. Attributes which take a value are followed by an * '=' and then an integer. Here's an example: "cols=6 rgap=2 cgap=5 * w". *

* Attributes are evaluated from left to right. If you duplicate an * attribute, the right-most one wins. *

All attributes can be specified for both the table and the * individual Components. Some attributes are only used by the table, * some are only used by the Components and some are used by both: the * table instance is the default which each Component can override. *

Rows and Columns

*

* When you create a table, you will almost always specify the number * of columns in it. The default is 1. Columns are filled from left to * right. When all columns are filled, a new row is automatically * created. *

* You can override the default Component placement somewhat with "col" * and "skip". col takes as a value, the column number in which the * Component should be placed. Column numbers begin with 0. The * default is to place the Component in the next available table cell. * One caveat when using col is that if you have already passed the * given column, the layout adds another row and places the Component * in the column on that new row. *

* "skip" allows you to skip a number of cells. The default is 0. If * the layout reaches the end of the row, skipping continues on the * next row. *

* You can make a Component span multiple rows or columns with rspan * and cspan. The default value for these is 1. Later components will * skip over any occupied cells, which is particularly important to * note for row spanning. *

Spacing

* The space the TableLayout works with is inside the Container's * insets. Some Containers have insets of 0 (e.g. JPanel) and most * don't allow you to alter the insets. Since you will often want to * control the space between the table and the edges of the Container, * an "extra" table inset can be given: titop, tibottom, tileft and * tiright. Each of these takes a value, the pixel offset from the top, * bottom, etc. The default value of each is 0. *

* You can create some space between cells in the table. This space is * only placed between cells; never along the edges of the * table. This allows you to nest table layouts and keep consistent * cell spacing. The attributes used are rgap and cgap and their * default value is 0. *

* Within a cell, you can also create some space between the cells * edges and the Component in the cell. The attributes are itop, * ibottom, ileft and iright. Their default value is 0. *

Placement and Filling

*

* Given that you have something to draw and a space to draw it in, * you have some choices as to where to place it and how to fill it, * particularly when the drawing area is bigger than required. *

* Placement attributes allow you to place the item in one of eight * compass directions or centered. The entire table can be placed * within the container using tn, tne, te, tse, ts, tsw, tw, tnw and * tc. Components can be placed within their cell using n, ne, e, se, * s, sw, w, nw and c. *

* Fill attributes allow you to fill the item to cover all available * space. Horizontal and vertical filling are handled separately. For * tables, the attributes are tfh, tfv and tf. "tf" fills in both * directions. For Components, use fh, fv and f. *

* Placement attributes turn off all filling. Fill attributes turn off * placement, but only in the fill direction. So "n fh" will stretch a * Component horizontally, but will place it at the "north" position * (at the top of the cell). *

* The default value for both the table and the individual Components * is to fill in both directions. You will almost always want to * specify your own values. *

Weighting

*

* When a table is filled, if the available space exceeds the space * required, we stretch the table to fill the space. This implies that * we have to stretch each cell. How much each cell should be filled * is what weighting is all about. The attributes are rweight and * cweight which take an integer weight factor. The default is 0. *

* Note that stretching a cell is not the same as stretching the * Component inside the cell unless the component uses filling. *

* If you'd like some simple rules of thumbs, use these: *

*

* Ok, here are the dirty details. *

* If the available size is greater than the table's preferred size * and table filling is enabled, weighting is used (they are otherwise * ignored). *

* Weights are obtained by looking at each row and column and locating * the largest weight; this becomes the row or column weight. If all * weights are 0, we treat them as though they are all 1. We create * a sum for all row weights and one for all column weights. This * number defines the number of units into which the excess space will * be divided. *

* For example, with three column weights of 1, 1, and 1, the space is * divided into 3 units. If the excess space is 30 pixels, each unit * is 10 pixels, which is the extra space each column receives. If the * column weights were 0, 2, and 1, the space is still divided into 3 * units. But the column weights specify how many units each column * receives. So, column 0 will receive nothing, column 1, 20 pixels * and column 2, 10 pixels. *

* Keep in mind that rows and columns are handled separately. One may * need filling and the other not. *

* When we don't have enough space for the preferred row or column * sizes, we ignore the user-defined weights and treat each row or * column as having equal weight. The approach then, is as above * except that we are reducing cell sizes. Another difference is that * no cell will be made smaller than its minimum size. *

Special Spanning Issues

* There are some special issues with row and column spanning. When * determining minimum or preferred sizes, we need to know what * portion of the Component's size to assign to each row and column * that it spans. We solve this by doing two passes. In the first, we * ignore spanning cells and determine row and column sizes without * them. In the second pass, we look to see if the spanning Component * will fit within the row and column sizes we determined. If not, we * currently distribute the extra space based on the row or column * weights of the rows or columns spanned. Someday, we may need to add * attributes to provide more control. *

* The row and column weights given are applied to the row or column * in which the Component begins. *

*

Summary

*

* This table summarizes the attribute information: *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
NameDescriptionHas Value?DefaultScope
colsNumber of columnsYes1Table
colPlace Component in this columnYesNext empty columnComponent
skipSkip a number of columnsYes0Component
rspan, cspanRow and column spanningYes1Component
titop, tibottom, tileft, tirightTable insetsYes0Table
rgap, cgapRow and column gapsYes0Table
itop, ibottom, ileft, irightComponent insetsYes0Table/Component
tn, tne, te, tse, ts, tsw, tw, tnw, tc, tf, tfh, tfvTable placement and fillNotfTable
n, ne, e, se, s, sw, w, nw, c, f, fh, fvComponent placement and fillNofTable/Component
rweight, cweightRow and column weightsYes0Table/Component
* * @author Antonio Freixas */ // Copyright © 2000-2004 Credence Systems Corporation. // All Rights Reserved. public class TableLayout implements LayoutManager2 { //********************************************************************** // Private Members //********************************************************************** // This is the set of attributes applied to the table. Some attributes // are used as cell defaults. Cell-only attributes are ignored private Attributes tableAttributes; // Attributes for each component can be found in these hash tables private HashMap compAttributes = new HashMap(); // These variables store information about the row/col arrangement of // the components. These are set by placeComponents() private int nRows = 0; private int nCols = 0; private Component[][] components = null; // We cache measureComponents() information so that it is recalculated // after invalidateLayout() is called private boolean useCacheMeasureResults = false; // These variables store sizing information set by measureComponents() private int[] minWidth; private int[] prefWidth; private int[] maxWidth; private int[] adjWidth; private int[] colWeight; private int[] minHeight; private int[] prefHeight; private int[] maxHeight; private int[] adjHeight; private int[] rowWeight; // These sizes are the minimum width for the table, not including // either the container's insets or the table's insets private int MinWidth = 0; private int MinHeight = 0; private int PrefWidth = 0; private int PrefHeight = 0; private int MaxWidth = 0; private int MaxHeight = 0; private int ColWeight = 0; private int RowWeight = 0; static private int classCount = 0; private int instanceCount = classCount++; //********************************************************************** // Constructors //********************************************************************** /** * Construct a new TableLayout. */ public TableLayout() { this(null); } /** * Construct a new TableLayout with the given attributes. * * @param attributes A list of attributes for the table. The list is * described in the class documentation above. Cell-only * attributes are ignored. */ public TableLayout( String attributes) { tableAttributes = new Attributes(attributes); } //********************************************************************** // Public //********************************************************************** /** * Reset the table attributes for the layout. * * @param attributes The new table attributes. */ public void setTableAttributes( String attributes) { // Set the attributes for the table tableAttributes = new Attributes(attributes); // Since the component attributes "inherit" from the table // attributes, any change to the table attributes causes us to // reprocess all existing component attributes Iterator iter = compAttributes.keySet().iterator(); while (iter.hasNext()) { Component comp = (Component)iter.next(); Attributes a = (Attributes)compAttributes.get(comp); a.parse(); // Re-parse } components = null; useCacheMeasureResults = false; } /** * Reset the attributes for a component in the layout. The component * must already have been added to the container or else this call has * no effect. * * @param comp The component to alter. * @param attributes The new attributes for the component. */ public void setAttributes( Component comp, String attributes) { if (compAttributes.get(comp) != null) { Attributes a = new Attributes(attributes, false); compAttributes.put(comp, a); components = null; useCacheMeasureResults = false; } } /** * Adds the component with the specified attributes to the layout. * * @param attributes A list of attributes for the component. The list * is described in the class documentation above. Table-only * attributes are ignored. * @param comp The component to be added. */ public void addLayoutComponent( String attributes, Component comp) { Attributes a = new Attributes(attributes, false); compAttributes.put(comp, a); components = null; useCacheMeasureResults = false; // DEBUG // if ("DEBUG".equals(comp.getName())) { // System.out.println( // "Adding comp " + comp.getClass().getName() + " " + a); // } } /** * Adds the specified component to the layout, using the specified * constraint object (which we expect to be a String of attributes). * * @param comp The component to be added. * @param constraints A list of attributes for the component. The list * is described in the class documentation above. Table-only * attributes are ignored. */ public void addLayoutComponent( Component comp, Object constraints) { String attributes = ""; if (constraints instanceof String) { attributes = (String)constraints; } addLayoutComponent(attributes, comp); } /** * Removes the specified component from the layout. * @param comp The component to be removed. */ public void removeLayoutComponent( Component comp) { compAttributes.remove(comp); components = null; } /** * Calculates the minimum size dimensions for the layout given the * components in the a parent container. * * @param parent The container to be laid out. * @return The minimum layout size. * @see #preferredLayoutSize(Container) * @see #maximumLayoutSize(Container) */ public Dimension minimumLayoutSize( Container parent) { Insets insets = parent.getInsets(); measureComponents(parent); int w = insets.left + insets.right + tableAttributes.tableInsets.left + tableAttributes.tableInsets.right + MinWidth; int h = insets.top + insets.bottom + tableAttributes.tableInsets.top + tableAttributes.tableInsets.bottom + MinHeight; if (w > Short.MAX_VALUE) w = Short.MAX_VALUE; if (h > Short.MAX_VALUE) h = Short.MAX_VALUE; return new Dimension(w, h); } /** * Calculates the preferred size dimensions for the layout given the * components in a parent container. * * @param parent The container to be laid out. * @return The preferred layout size. * @see #minimumLayoutSize(Container) * @see #maximumLayoutSize(Container) */ public Dimension preferredLayoutSize( Container parent) { Insets insets = parent.getInsets(); measureComponents(parent); int w = insets.left + insets.right + tableAttributes.tableInsets.left + tableAttributes.tableInsets.right + PrefWidth; int h = insets.top + insets.bottom + tableAttributes.tableInsets.top + tableAttributes.tableInsets.bottom + PrefHeight; if (w > Short.MAX_VALUE) w = Short.MAX_VALUE; if (h > Short.MAX_VALUE) h = Short.MAX_VALUE; return new Dimension(w, h); } /** * Calculates the maximum size dimensions for the layout given the * components in a parent container. * * @param parent The container parent. * @return The maximum layout size. * @see #minimumLayoutSize(Container) * @see #preferredLayoutSize(Container) */ public Dimension maximumLayoutSize( Container parent) { Insets insets = parent.getInsets(); measureComponents(parent); // Note that the maximum size of the container is not the maximum // size of the table if the fill options are not used int w = Short.MAX_VALUE; if (tableAttributes.tableHorizontal != Attributes.FILL) { w = insets.left + insets.right + tableAttributes.tableInsets.left + tableAttributes.tableInsets.right + MaxWidth; if (w > Short.MAX_VALUE) w = Short.MAX_VALUE; } int h = Short.MAX_VALUE; if (tableAttributes.tableVertical != Attributes.FILL) { h = insets.top + insets.bottom + tableAttributes.tableInsets.top + tableAttributes.tableInsets.bottom + MaxHeight; if (h > Short.MAX_VALUE) h = Short.MAX_VALUE; } return new Dimension(w, h); } /** * Returns the alignment along the x axis. This always returns 0.5. * * @param parent The container whose alignment we want. * @return The alignment along the x axis. */ public float getLayoutAlignmentX( Container parent) { return 0.5f; } /** * Returns the alignment along the y axis. This always returns 0.5. * * @param parent The container whose alignment we want. * @return The alignment along the y axis. */ public float getLayoutAlignmentY( Container parent) { return 0.5f; } /** * Invalidates the layout. Cached information will be discarded. * * @param parent The container whose alignment we want. */ public void invalidateLayout( Container parent) { useCacheMeasureResults = false; } /** * Lays out the components in the given container. * * @param parent The container which needs to be laid out. */ public void layoutContainer( Container parent) { // Get the row and column measurements measureComponents(parent); // Get the parent insets and determine the full amount of space we // have available Insets insets = parent.getInsets(); int fullWidth = parent.getSize().width - (insets.left + insets.right) - (tableAttributes.tableInsets.left + tableAttributes.tableInsets.right); int fullHeight = parent.getSize().height - (insets.top + insets.bottom) - (tableAttributes.tableInsets.top + tableAttributes.tableInsets.bottom); // We normally draw each row and column in its preferred size. If // we have more space, we grow the cells. If less, we shrink the // cells boolean shrinkWidth = fullWidth < PrefWidth; boolean shrinkHeight = fullHeight < PrefHeight; // Get the position and size of the table. There are three // possibilities for the table size: // // * The available space equals or exceeds the preferred size // and the table is filled - use the full space available. We // will expand the cells in a later step. // // * The available space equals or exceeds the preferred size // and the table is not filled - use the preferred size. // // * The available space is less than the preferred size - use // the available space. We will shrink the cells in a later // step. int tableX = insets.left + tableAttributes.tableInsets.left; int tableY = insets.top + tableAttributes.tableInsets.top; int tableWidth = PrefWidth; if (shrinkWidth || tableAttributes.tableHorizontal == Attributes.FILL) { tableWidth = fullWidth; } int tableHeight = PrefHeight; if (shrinkHeight || tableAttributes.tableVertical == Attributes.FILL) { tableHeight = fullHeight; } if (tableAttributes.tableHorizontal == Attributes.CENTER || tableAttributes.tableHorizontal == Attributes.FILL) { tableX += (fullWidth - tableWidth) / 2; } else if (tableAttributes.tableHorizontal == Attributes.RIGHT) { tableX += fullWidth - tableWidth; } if (tableAttributes.tableVertical == Attributes.CENTER || tableAttributes.tableVertical == Attributes.FILL) { tableY += (fullHeight - tableHeight) / 2; } else if (tableAttributes.tableVertical == Attributes.BOTTOM) { tableY += fullHeight - tableHeight; } // Now adjust the column and row cell sizes adjustCellSizes( nCols, (tableAttributes.tableHorizontal == Attributes.FILL), shrinkWidth, minWidth, PrefWidth, prefWidth, fullWidth, ColWeight, colWeight, adjWidth, parent); adjustCellSizes( nRows, (tableAttributes.tableVertical == Attributes.FILL), shrinkHeight, minHeight, PrefHeight, prefHeight, fullHeight, RowWeight, rowWeight, adjHeight, parent); // Begin the component layout loop for (int r = 0; r < nRows; r++) { for (int c = 0; c < nCols; c++) { Component comp = components[r][c]; if (comp == null) continue; Attributes attributes = (Attributes)compAttributes.get(comp); Dimension compMinSize = comp.getMinimumSize(); Dimension compPrefSize = comp.getPreferredSize(); Dimension compMaxSize = comp.getMaximumSize(); // Base position int compX = tableX + (tableAttributes.cGap * c) + attributes.cellInsets.left; for (int i = 0; i < c; i++) compX += adjWidth[i]; int compY = tableY + (tableAttributes.rGap * r) + attributes.cellInsets.top; for (int i = 0; i < r; i++) compY += adjHeight[i]; // Get the cell size. This has to take into account row // and column spanning int cellWidth = adjWidth[c]; for (int i = 1; i < attributes.cSpan; i++) { cellWidth += tableAttributes.cGap + adjWidth[c + i]; } int cellHeight = adjHeight[r]; for (int i = 1; i < attributes.rSpan; i++) { cellHeight += tableAttributes.rGap + adjHeight[r + i]; } int insetCellWidth = cellWidth - attributes.cellInsets.left - attributes.cellInsets.right; int insetCellHeight = cellHeight - attributes.cellInsets.top - attributes.cellInsets.bottom; // Get the component size. Use the preferred size, if // possible. If not use the cell size minus insets int compWidth = compPrefSize.width; int compHeight = compPrefSize.height; if (compWidth > insetCellWidth) compWidth = insetCellWidth; if (compHeight > insetCellHeight) compHeight = insetCellHeight; // Adjust for fill if (attributes.horizontal == Attributes.FILL) { compWidth = insetCellWidth; compWidth = Math.max(compWidth, compMinSize.width); // Some components (like JButton) can exceed their max size // compWidth = Math.min(compWidth, compMaxSize.width); } if (attributes.vertical == Attributes.FILL) { compHeight = insetCellHeight; compHeight = Math.max(compHeight, compMinSize.height); // Some components (like JButton) can exceed their max size // compHeight = Math.min(compHeight, compMaxSize.height); } // Position properly. We treat FILL like CENTER since // the min/max limits may have prevented us from really // filling if (attributes.horizontal == Attributes.CENTER || attributes.horizontal == Attributes.FILL) { compX += (cellWidth - (attributes.cellInsets.left + attributes.cellInsets.right) - compWidth) / 2; } else if (attributes.horizontal == Attributes.RIGHT) { compX += (cellWidth - (attributes.cellInsets.left + attributes.cellInsets.right) - compWidth); } if (attributes.vertical == Attributes.CENTER || attributes.vertical == Attributes.FILL) { compY += (cellHeight - (attributes.cellInsets.top + attributes.cellInsets.bottom) - compHeight) / 2; } else if (attributes.vertical == Attributes.BOTTOM) { compY += (cellHeight - (attributes.cellInsets.top + attributes.cellInsets.bottom) - compHeight); } // Place the component comp.setBounds(compX, compY, compWidth, compHeight); // DEBUG // if ("DEBUG".equals(parent.getName())) { // System.out.println("Placing component " + // comp.getClass().getName() + // " (" + compX + ", " + compY + ") " + // compWidth + " x " + compHeight); // } } } } // The inherited toString() method is acceptable. //********************************************************************** // Private //********************************************************************** /** * The row or column sizes need to be adjusted. We may want to grow * or shrink the sizes, based on whether the available space is larger * or smaller than the preferred size. *

* If we grow the table, we pay attention to the user's weighting * factors. If we shrink the table, we assign all cells a weight * factor of 1. * * @param nCells The number of cells in the row or column. * @param fill True if the table rows or columns should fill the * available space. * @param shrink True if the available size is less than the preferred * size. * @param minSize The minimum sizes of each row or column. * @param PrefSize The sum of the preferred sizes of all cells in the * row or column plus any cell gaps. * @param prefSize The preferred sizes of each row or column. * @param CellWeight The sum of all cell weights in the row or column. * @param cellWeight The weight of each row or column. * @param adjSize The adjusted size of each row or column. The * contents of this array are set and returned. */ private void adjustCellSizes( int nCells, boolean fill, boolean shrink, int[] minSize, int PrefSize, int[] prefSize, int fullSize, int CellWeight, int[] cellWeight, int[] adjSize, Container parent) { // The sum of the weights (CellWeight) determines how many units // any excess (or reduced) space should be divided into. The // unitOfSpace variable is the size of each unit. // // We use weighting under two conditions: // // * We are shrinking the table. // // * We have more space than we need and the user asked us to // fill the available space // // When we have more than enough space for the preferred row and // column sizes, we follow the user's weighting. There is a // special case if all weights are 0: the weights are treated as // thought they were all 1. // // When do not have enough space, we weight everything the same. double unitOfSpace = 0.0; if (shrink || fill) { unitOfSpace = (double)(fullSize - PrefSize) / (double)((shrink || CellWeight == 0) ? nCells : CellWeight); } else { // No adjustment needed: use the preferred sizes for (int i = 0; i < nCells; i++) { adjSize[i] = prefSize[i]; } return; } double extraSpace; int iExtraSpace; double error = 0.0; int iError = -999999; int adjWeight; for (int i = 0; i < nCells; i++) { // Initialize the adjusted size to the preferred size adjSize[i] = prefSize[i]; // Get the cell weight based on various conditions adjWeight = (shrink || CellWeight == 0) ? 1 : cellWeight[i]; // Determine how much extra space to give each cell. The space // is the weight (number of units) times the unit size. We can // only assign an integer number of pixels, which creates a // fractional error extraSpace = unitOfSpace * adjWeight; iExtraSpace = (int)extraSpace; adjSize[i] += iExtraSpace; error += extraSpace - iExtraSpace; iError = (int)error; // Increment/decrement this cell by the accumulated integer // error, if it's not 0 if (shrink) { if (iError < 0) { adjSize[i] += iError; } } else { if (iError > 0) { adjSize[i] += iError; } } error -= iError; // If we're shrinking, we need to prevent any cell from // shrinking below its minimum size. The error is adjusted to // include the space added to the cell if (shrink && (adjSize[i] < minSize[i])) { error -= minSize[i] - adjSize[i]; adjSize[i] = minSize[i]; } iError = (int)error; } // If we are growing, the error should be less than 1 pixel. If we // are shrinking, we limit each cell to its minimum size, so we // can accumulate larger errors as cells refuse to shrink. So we // distribute the error to cells that can still shrink. We repeat // this until we've reduced the error to 0 or we're unable to // shrink the error anymore. // // Remember that iError is a negative number if (shrink || iError < 0) { int lastIError; do { lastIError = iError; for (int i = 0; i < nCells; i++) { // If the cell is already at its minimum size, skip it if (adjSize[i] > minSize[i]) { adjSize[i]--; iError++; } } } while (iError < 0 && iError > lastIError); } // DEBUG // if ("DEBUG".equals(parent.getName())) { // System.out.println(" iError " + iError); // for (int i = 0; i < nCells; i++) { // System.out.println(" " + i + ") Adjusted size = " + adjSize[i]); // } // } } /** * For each component, determine its row/col position and place it in * an array for easy access later. Elements spanning multiple rows * and/or columns are placed in the NW row/col slot in the array. * Results are placed in class fields. * * @param parent The parent container. */ private void placeComponents( Container parent) { // If we haven't added or removed a component since the last time // placeComponents() was called, we assume the current results are // OK if (components != null) return; int compCount = parent.getComponentCount(); // Get the number of columns specified by the user nCols = tableAttributes.columns; // Create the array of components CompArray compArray = new CompArray(tableAttributes.columns, compCount); // Fill the array with components, taking row/column spanning // into account int row = 0; int col = 0; for (int i = 0; i < compCount; i++) { // Get the next component and its options Component comp = parent.getComponent(i); Attributes attributes = (Attributes)compAttributes.get(comp); // If the column span is greater than the column size, // truncate it to the column size attributes.cSpan = attributes.originalCSpan; if (attributes.cSpan > tableAttributes.columns) { attributes.cSpan = tableAttributes.columns; } // Handle options to force us to column 0 or to skip columns if (attributes.column != Attributes.NEXT_COLUMN) { if (col > attributes.column) row++; col = attributes.column; } col += attributes.skip; if (col >= nCols) { row++; col = 0; } // Skip over any cells that are already occupied while (compArray.get(row, col) != null) { col++; if (col >= nCols) { row++; col = 0; } } // If spanning multiple columns, will we fit on this row? if (col + attributes.cSpan > nCols) { row++; col = 0; } // For now, fill all the cells that are occupied by this // component for (int c = 0; c < attributes.cSpan; c++) { for (int r = 0; r < attributes.rSpan; r++) { compArray.set(row + r, col + c, comp); } } // Advance to the next cell, ready for the next component col += attributes.cSpan; if (col >= nCols) { row++; col = 0; } } // Now we know how many rows there are. We can use a normal, // properly sized array from now on. The array returned includes // the maximum row into which anything was entered, including any // row spans components = compArray.getArray(); nRows = components.length; // Now we've positioned our components we can thin out the cells so // we only remember the top left corner of each component for (row = 0; row < nRows; row++) { for (col = 0; col < nCols; col++) { Component comp = components[row][col]; for (int r = row; r < nRows && components[r][col] == comp; r++) { for (int c = col; c < nCols && components[r][c] == comp; c++) { if (r > row || c > col) { components[r][c] = null; } } } } } // DEBUG // if ("DEBUG".equals(parent.getName())) { // System.out.println("placeComponents finished: rows = " + // nRows + " cols = " + nCols); // for (int r = 0; r < nRows; r++) { // System.out.println("Row " + r + ":"); // for (int c = 0; c < nCols; c++) { // System.out.println(" Col " + c + " Comp " + // ((components[r][c] == null) ? // "none" : // components[r][c].getClass().getName())); // } // } // } } /** * In this method, we will determine the minimum, preferred and * maximum sizes of the components as layed out by the table layout * manager * * @param parent The parent container. */ private void measureComponents( Container parent) { if (useCacheMeasureResults) return; // Determine the row/col positions for the components placeComponents(parent); // Allocate new arrays to store row and column preferred and min // sizes, but only if the old arrays aren't big enough if (minWidth == null || minWidth.length < nCols) { minWidth = new int[nCols]; prefWidth = new int[nCols]; maxWidth = new int[nCols]; adjWidth = new int[nCols]; colWeight = new int[nCols]; } if (minHeight == null || minHeight.length < nRows) { minHeight = new int[nRows]; prefHeight = new int[nRows]; maxHeight = new int[nRows]; adjHeight = new int[nRows]; rowWeight = new int[nRows]; } for (int i = 0; i < nCols; i++) { minWidth[i] = 0; prefWidth[i] = 0; maxWidth[i] = 0; colWeight[i] = 0; } for (int i = 0; i < nRows; i++) { minHeight[i] = 0; prefHeight[i] = 0; maxHeight[i] = 0; rowWeight[i] = 0; } // Measure the minimum and preferred size of each row and column for (int row = 0; row < nRows; row++) { for (int col = 0; col < nCols; col++) { Component comp = components[row][col]; if (comp != null) { Attributes attributes = (Attributes)compAttributes.get(comp); Dimension minSize = new Dimension(comp.getMinimumSize()); Dimension prefSize = new Dimension(comp.getPreferredSize()); Dimension maxSize = new Dimension(comp.getMaximumSize()); // Add the cell insets minSize.width += attributes.cellInsets.left + attributes.cellInsets.right; minSize.height += attributes.cellInsets.top + attributes.cellInsets.bottom; prefSize.width += attributes.cellInsets.left + attributes.cellInsets.right; prefSize.height += attributes.cellInsets.top + attributes.cellInsets.bottom; maxSize.width += attributes.cellInsets.left + attributes.cellInsets.right; maxSize.height += attributes.cellInsets.right + attributes.cellInsets.bottom; // Make sure that 0 <= minSize <= prefSize <= maxSize limitDimension(minSize, new Dimension(0, 0)); limitDimension(prefSize, minSize); limitDimension(maxSize, prefSize); // First pass, we determine the sizes while ignoring // components which span columns or rows if (attributes.cSpan == 1) { minWidth[col] = Math.max(minSize.width, minWidth[col]); prefWidth[col] = Math.max(prefSize.width, prefWidth[col]); maxWidth[col] = Math.max(maxSize.width, maxWidth[col]); } if (attributes.rSpan == 1) { minHeight[row] = Math.max(minSize.height, minHeight[row]); prefHeight[row] = Math.max(prefSize.height, prefHeight[row]); maxHeight[row] = Math.max(maxSize.height, maxHeight[row]); } // Get the row and column weights. The weight is the // maximum value for the row or column if (attributes.cWeight > colWeight[col]) { colWeight[col] = attributes.cWeight; } if (attributes.rWeight > rowWeight[row]) { rowWeight[row] = attributes.rWeight; } } } } // Do it again, but just for components which span multiple cells. // for (int row = 0; row < nRows; row++) { for (int col = 0; col < nCols; col++) { Component comp = components[row][col]; if (comp != null) { Attributes attributes = (Attributes)compAttributes.get(comp); if (attributes.rSpan == 1 && attributes.cSpan == 1) continue; Dimension minSize = new Dimension(comp.getMinimumSize()); Dimension prefSize = new Dimension(comp.getPreferredSize()); Dimension maxSize = new Dimension(comp.getMaximumSize()); // Add the cell insets minSize.width += attributes.cellInsets.top + attributes.cellInsets.bottom; minSize.height += attributes.cellInsets.left + attributes.cellInsets.right; prefSize.width += attributes.cellInsets.top + attributes.cellInsets.bottom; prefSize.height += attributes.cellInsets.left + attributes.cellInsets.right; maxSize.width += attributes.cellInsets.top + attributes.cellInsets.bottom; maxSize.height += attributes.cellInsets.left + attributes.cellInsets.right; // Make sure that 0 <= minSize <= prefSize <= maxSize limitDimension(minSize, new Dimension(0, 0)); limitDimension(prefSize, minSize); limitDimension(maxSize, prefSize); if (attributes.cSpan > 1) { adjustForSpans(col, minSize.width, minWidth, colWeight, attributes.cSpan, tableAttributes.cGap); adjustForSpans(col, prefSize.width, prefWidth, colWeight, attributes.cSpan, tableAttributes.cGap); adjustForSpans(col, maxSize.width, maxWidth, colWeight, attributes.cSpan, tableAttributes.cGap); } if (attributes.rSpan > 1) { adjustForSpans(row, minSize.height, minHeight, rowWeight, attributes.rSpan, tableAttributes.rGap); adjustForSpans(row, prefSize.height, prefHeight, rowWeight, attributes.rSpan, tableAttributes.rGap); adjustForSpans(row, maxSize.height, maxHeight, rowWeight, attributes.rSpan, tableAttributes.rGap); } } } } // Add up all the individual values MinWidth = 0; MinHeight = 0; PrefWidth = 0; PrefHeight = 0; MaxWidth = 0; MaxHeight = 0; ColWeight = 0; RowWeight = 0; // Sum up everything for (int i = 0; i < nCols; i++) { MinWidth += minWidth[i]; PrefWidth += prefWidth[i]; MaxWidth += maxWidth[i]; ColWeight += colWeight[i]; } for (int i = 0; i < nRows; i++) { MinHeight += minHeight[i]; PrefHeight += prefHeight[i]; MaxHeight += maxHeight[i]; RowWeight += rowWeight[i]; } // Add in the table gaps int cExtra = tableAttributes.cGap * (nCols - 1); int rExtra = tableAttributes.rGap * (nRows - 1); MinWidth += cExtra; PrefWidth += cExtra; MaxWidth += cExtra; MinHeight += rExtra; PrefHeight += rExtra; MaxHeight += rExtra; // DEBUG // if ("DEBUG".equals(parent.getName())) { // System.out.println("MeasureComponents:"); // System.out.println(" Min " + MinWidth + ", " + MinHeight); // System.out.println(" Pref " + PrefWidth + ", " + PrefHeight); // System.out.println(" Max " + MaxWidth + ", " + MaxHeight); // System.out.println(" Weight " + ColWeight + ", " + RowWeight ); // for (int c = 0; c < nCols; c++) { // System.out.println(" Col " + c + // " min " + minWidth[c] + // " pref " + prefWidth[c] + // " max " + maxWidth[c] + // " wgt " + colWeight[c]); // } // for (int r = 0; r < nRows; r++) { // System.out.println(" Row " + r + // " min " + minHeight[r] + // " pref " + prefHeight[r] + // " max " + maxHeight[r] + // " wgt " + rowWeight[r]); // } // } // We keep using these results until the layout is invalidated useCacheMeasureResults = true; } /** * Make sure the first dimension is greater than or equal to the * second. Also make sure the first dimension is less than an absolute * maximum. * * @param d1 The first dimension (may be modified). * @param d2 The second dimension (will not be modified). */ private void limitDimension( Dimension d1, Dimension d2) { if (d1.width < d2.width) d1.width = d2.width; if (d1.height < d2.height) d1.height = d2.height; if (d1.width > Short.MAX_VALUE) d1.width = Short.MAX_VALUE; if (d1.height > Short.MAX_VALUE) d1.height = Short.MAX_VALUE; } /** * If a component spans multiple rows or columns, we need to * distribute portions of its size to the individual rows and columns. * * @param pos Row or column position where the span component starts. * @param compSize The height or width of the component * @param sizes The array of widths or heights to adjust. * @param span The number of cells spanned by the component. * @param gap The row or column gap. */ private void adjustForSpans( int pos, int compSize, int[] sizes, int[] weight, int span, int gap) { // The total size is the size of the rows or columns plus all the // space in between int totalSize = 0; for (int i = 0; i < span; i++) { totalSize += sizes[pos + i]; } totalSize += gap * (span - 1); // If the spanned component is bigger than the the rows or columns // it spans, we divide the extra space based on the weights of the // spanned rows or columns if (compSize > totalSize) { int extra = compSize - totalSize; int totalWeight = 0; for (int i = 0; i < span; i++) { totalWeight += weight[pos + i]; } if (totalWeight == 0) totalWeight = span; int remainder = extra; for (int i = 0; i < span; i++) { int portion = (extra * weight[pos + i]) / totalWeight; sizes[pos + i] += portion; remainder -= portion; } // Because of truncation, we may have a little left over which // we give to the last row or column if (remainder > 0) { sizes[pos + span - 1] += remainder; } } } //********************************************************************** // Inner Classes //********************************************************************** //********************************************************************** // // Attributes // // This class converts a string attribute into a data structure. // //********************************************************************** // Attributes not needing assigment static String[] attr = { "tn", "tne", "tnw", "ts", "tse", "tsw", "te", "tw", "tc", "tfh", "tfv", "tf", "n", "ne", "nw", "s", "se", "sw", "e", "w", "c", "fh", "fv", "f", }; // Attributes needing assigment static String[] assgn = { "cols", "rgap", "cgap", "titop", "tibottom", "tileft", "tiright", "itop", "ibottom", "ileft", "iright", "rweight", "cweight", "rspan", "cspan", "col", "skip" }; private class Attributes { // Constants used for fill and placement operations static final int CENTER = 0; static final int LEFT = 1; static final int RIGHT = 2; static final int TOP = 3; static final int BOTTOM = 4; static final int FILL = 5; // Constants for column placement static final int NEXT_COLUMN = -1; // The attributes in their original string form String attrString; // Table-only options int columns = 1; int tableHorizontal = FILL; int tableVertical = FILL; int rGap = 0; int cGap = 0; Insets tableInsets = new Insets(0, 0, 0, 0); // Table/cell options int horizontal = FILL; int vertical = FILL; Insets cellInsets = new Insets(0, 0, 0, 0); int rWeight = 0; int cWeight = 0; // Cell-only options int rSpan = 1; int cSpan = 1; int originalCSpan = cSpan; int column = NEXT_COLUMN; int skip = 0; int tkPos = 0; boolean isTableAttributes = false; Attributes( String attrString) { this(attrString, true); } Attributes( String attrString, boolean isTableAttributes) { // Save the string for later access this.attrString = attrString; this.isTableAttributes = isTableAttributes; parse(); } public String toString() { String sep = System.getProperty("line.separator"); return "TableLayout Attributes:" + sep + "isTableAttributes = " + isTableAttributes + sep + "columns = " + columns + sep + "tableHorizontal = " + tableHorizontal + " " + "tableVertical = " + tableVertical + sep + "rGap = " + rGap + " " + "cGap = " + cGap + sep + "tableInsets = " + tableInsets + sep + "horizontal = " + horizontal + " " + "vertical = " + vertical + sep + "cellInsets = " + cellInsets + sep + "rWeight = " + rWeight + " " + "cWeight = " + cWeight + sep + "rSpan = " + rSpan + " " + "cSpan = " + cSpan + sep + "originalCSpan = " + originalCSpan + sep + "column = " + column + sep + "skip = " + skip; } String getStringAttributes() { return attrString; } private char getTokenChar() { if (tkPos >= attrString.length()) return 0; return Character.toLowerCase(attrString.charAt(tkPos++)); } private String getToken() { StringBuffer token = new StringBuffer(); char c = getTokenChar(); // Skip whitespace if (Character.isWhitespace(c)) { do { c = getTokenChar(); } while (Character.isWhitespace(c)); } // Attributes if (Character.isLetter(c)) { do { token.append(c); c = getTokenChar(); } while (Character.isLetter(c)); if (c != 0) tkPos--; } // Integers else if (Character.isDigit(c)) { do { token.append(c); c = getTokenChar(); } while (Character.isDigit(c)); if (c != 0) tkPos--; } // End of string else if (c == 0) { return null; } // Everything else is a single-character token else { token.append(c); } return new String(token); } void parse() { // Initialize this set of attributes so it starts out as a copy of // the given default, at least for those options where the cell // can override a table default if (!isTableAttributes) { horizontal = tableAttributes.horizontal; vertical = tableAttributes.vertical; cellInsets = (Insets)tableAttributes.cellInsets.clone(); rWeight = tableAttributes.rWeight; cWeight = tableAttributes.cWeight; } if (attrString == null) return; tkPos = 0; while (tkPos < attrString.length()) { parseOption(); } // We have checked the syntax, now check the semantics if (isTableAttributes) { if (columns == 0) { reportSemanticError("cols=0"); } } else { if (rSpan == 0) { reportSemanticError("rspan=0"); } if (cSpan == 0) { reportSemanticError("cspan=0"); } if (column >= tableAttributes.columns) { reportSemanticError("col=" + column + " (max is " + (tableAttributes.columns - 1) + ")"); } } } private void parseOption() { // Get the next token String token = getToken(); if (token == null) return; boolean attributeFound = false; for (int i = 0; i < attr.length; i++) { if (token.equals(attr[i])) { parseAttribute(token); return; } } for (int i = 0; i < assgn.length; i++) { if (token.equals(assgn[i])) { parseAssignment(token); return; } } reportError(token, "Unrecognized attribute"); } private void parseAttribute( String token) { // Table placement and fill if ("tnw".equals(token) || "tw".equals(token) || "tsw".equals(token)) { tableHorizontal = LEFT; } if ("tne".equals(token) || "te".equals(token) || "tse".equals(token)) { tableHorizontal = RIGHT; } if ("tn".equals(token) || "tc".equals(token) || "ts".equals(token)) { tableHorizontal = CENTER; } if ("tf".equals(token) || "tfh".equals(token)) { tableHorizontal = FILL; } if ("tn".equals(token) || "tnw".equals(token) || "tne".equals(token)) { tableVertical = TOP; } if ("ts".equals(token) || "tsw".equals(token) || "tse".equals(token)) { tableVertical = BOTTOM; } if ("tw".equals(token) || "tc".equals(token) || "te".equals(token)) { tableVertical = CENTER; } if ("tf".equals(token) || "tfv".equals(token)) { tableVertical = FILL; } // Cell placement and fill if ("nw".equals(token) || "w".equals(token) || "sw".equals(token)) { horizontal = LEFT; } if ("ne".equals(token) || "e".equals(token) || "se".equals(token)) { horizontal = RIGHT; } if ("n".equals(token) || "c".equals(token) || "s".equals(token)) { horizontal = CENTER; } if ("f".equals(token) || "fh".equals(token)) { horizontal = FILL; } if ("n".equals(token) || "nw".equals(token) || "ne".equals(token)) { vertical = TOP; } if ("s".equals(token) || "sw".equals(token) || "se".equals(token)) { vertical = BOTTOM; } if ("w".equals(token) || "c".equals(token) || "e".equals(token)) { vertical = CENTER; } if ("f".equals(token) || "fv".equals(token)) { vertical = FILL; } } private void parseAssignment( String token) { String attr = token; token = getToken(); if (token != null) { if ("=".equals(token)) { token = getToken(); if (token != null) { int value = 0; try { value = Integer.parseInt(token); } catch (NumberFormatException e) { reportError(token, "Expected an integer"); } if ("cols".equals(attr)) columns = value; else if ("rgap".equals(attr)) rGap = value; else if ("cgap".equals(attr)) cGap = value; else if ("titop".equals(attr)) tableInsets.top = value; else if ("tibottom".equals(attr)) tableInsets.bottom = value; else if ("tileft".equals(attr)) tableInsets.left = value; else if ("tiright".equals(attr)) tableInsets.right = value; else if ("itop".equals(attr)) cellInsets.top = value; else if ("ibottom".equals(attr)) cellInsets.bottom = value; else if ("ileft".equals(attr)) cellInsets.left = value; else if ("iright".equals(attr)) cellInsets.right = value; else if ("rweight".equals(attr)) rWeight = value; else if ("cweight".equals(attr)) cWeight = value; else if ("rspan".equals(attr)) rSpan = value; else if ("cspan".equals(attr)) originalCSpan = cSpan = value; else if ("col".equals(attr)) column = value; else if ("skip".equals(attr)) skip = value; return; } } reportError(token, "Expected an '='"); } reportError(token, "Expected an '='"); } private void reportError( String token, String message) { throw new IllegalArgumentException( "TableLayout: " + message + "; near '" + token + "' at position " + tkPos + " in '" + attrString + "'"); } private void reportSemanticError( String message) { throw new IllegalArgumentException( "TableLayout: Invalid value: " + message); } } //********************************************************************** // // CompArray // // We'd like to use a 2-dimensional array to help us sort out the // layout of the various components. But in order to create the array, // we need to know the number of rows. In order to get the number of // rows, we need to lay out the components. So we have problem. // // It is not obvious how to determine the number of rows from the // component count, due to row and column spans. So we've created the // CompArray class to help out. It makes its best guess at the size of // the array. If we need additional rows, it expands the array as // efficiently as it can. When we're done, we can ask it to create a // correctly sized array to hold our data. // //********************************************************************** private class CompArray { private int nCols; private int nRows; private int maxRow = 0; Component[][] compArray = null; CompArray( int nCols, int compCount) { this.nRows = (compCount + (nCols - 1)) / nCols; this.nRows = Math.max(this.nRows, 1); this.nCols = nCols; compArray = new Component[nRows][]; for (int i = 0; i < nRows; i++) { compArray[i] = new Component[nCols]; Arrays.fill(compArray[i], null); } } Component get( int row, int col) { if (row >= nRows) resize(row + 1); return compArray[row][col]; } void set( int row, int col, Component comp) { if (row >= nRows) resize(row + 1); compArray[row][col] = comp; maxRow = Math.max(row, maxRow); } Component[][] getArray() { int maxRows = maxRow + 1; Component[][] array = new Component[maxRows][]; for (int r = 0; r < maxRows; r++) { array[r] = new Component[nCols]; System.arraycopy(compArray[r], 0, array[r], 0, nCols); } return array; } private void resize( int newRows) { // When we exceed a threshold, bump up the size by at least 10 if (newRows - nRows < 10) newRows = nRows + 10; // Create the new row array and copy the old one into it Component[][] newArray = new Component[newRows][]; System.arraycopy(compArray, 0, newArray, 0, nRows); // Initialize each new row to nulls for (int i = nRows; i < newRows; i++) { newArray[i] = new Component[nCols]; Arrays.fill(newArray[i], null); } compArray = newArray; nRows = newRows; } } //********************************************************************** // End Inner Classes //********************************************************************** }