org.eclipse.swt.layout.GridLayout Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2000, 2008 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.layout;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Layout;
import org.eclipse.swt.widgets.Scrollable;
/**
* Instances of this class lay out the control children of a
* Composite in a grid.
*
* GridLayout has a number of configuration fields, and the
* controls it lays out can have an associated layout data object, called
* GridData. The power of GridLayout lies in the
* ability to configure GridData for each control in the layout.
*
*
* The following code creates a shell managed by a GridLayout
* with 3 columns:
*
* Display display = new Display();
* Shell shell = new Shell(display);
* GridLayout gridLayout = new GridLayout();
* gridLayout.numColumns = 3;
* shell.setLayout(gridLayout);
*
* The numColumns field is the most important field in a
* GridLayout. Widgets are laid out in columns from left
* to right, and a new row is created when numColumns + 1
* controls are added to the Composite.
*
*
* @see GridData
* @see GridLayout snippets
* @see SWT Example: LayoutExample
* @see Sample code and further information
* @since 1.0
*/
public final class GridLayout extends Layout {
/**
* numColumns specifies the number of cell columns in the layout.
* If numColumns has a value less than 1, the layout will not
* set the size and position of any controls.
*
* The default value is 1.
*/
public int numColumns = 1;
/**
* makeColumnsEqualWidth specifies whether all columns in the layout
* will be forced to have the same width.
*
* The default value is false.
*/
public boolean makeColumnsEqualWidth = false;
/**
* marginWidth specifies the number of pixels of horizontal margin
* that will be placed along the left and right edges of the layout.
*
* The default value is 5.
*/
public int marginWidth = 5;
/**
* marginHeight specifies the number of pixels of vertical margin
* that will be placed along the top and bottom edges of the layout.
*
* The default value is 5.
*/
public int marginHeight = 5;
/**
* marginLeft specifies the number of pixels of horizontal margin
* that will be placed along the left edge of the layout.
*
* The default value is 0.
*/
public int marginLeft = 0;
/**
* marginTop specifies the number of pixels of vertical margin
* that will be placed along the top edge of the layout.
*
* The default value is 0.
*/
public int marginTop = 0;
/**
* marginRight specifies the number of pixels of horizontal margin
* that will be placed along the right edge of the layout.
*
* The default value is 0.
*/
public int marginRight = 0;
/**
* marginBottom specifies the number of pixels of vertical margin
* that will be placed along the bottom edge of the layout.
*
* The default value is 0.
*/
public int marginBottom = 0;
/**
* horizontalSpacing specifies the number of pixels between the right
* edge of one cell and the left edge of its neighbouring cell to
* the right.
*
* The default value is 5.
*/
public int horizontalSpacing = 5;
/**
* verticalSpacing specifies the number of pixels between the bottom
* edge of one cell and the top edge of its neighbouring cell underneath.
*
* The default value is 5.
*/
public int verticalSpacing = 5;
/**
* Constructs a new instance of this class
* with a single column.
*/
public GridLayout () {}
/**
* Constructs a new instance of this class given the
* number of columns, and whether or not the columns
* should be forced to have the same width.
* If numColumns has a value less than 1, the layout will not
* set the size and position of any controls.
*
* @param numColumns the number of columns in the grid
* @param makeColumnsEqualWidth whether or not the columns will have equal width
*/
public GridLayout (int numColumns, boolean makeColumnsEqualWidth) {
this.numColumns = numColumns;
this.makeColumnsEqualWidth = makeColumnsEqualWidth;
}
protected Point computeSize (Composite composite, int wHint, int hHint, boolean flushCache) {
Point size = layout (composite, false, 0, 0, wHint, hHint, flushCache);
if (wHint != SWT.DEFAULT) size.x = wHint;
if (hHint != SWT.DEFAULT) size.y = hHint;
return size;
}
protected boolean flushCache (Control control) {
Object data = control.getLayoutData ();
if (data != null) ((GridData) data).flushCache ();
return true;
}
GridData getData (Control [][] grid, int row, int column, int rowCount, int columnCount, boolean first) {
Control control = grid [row] [column];
if (control != null) {
GridData data = (GridData) control.getLayoutData ();
int hSpan = Math.max (1, Math.min (data.horizontalSpan, columnCount));
int vSpan = Math.max (1, data.verticalSpan);
int i = first ? row + vSpan - 1 : row - vSpan + 1;
int j = first ? column + hSpan - 1 : column - hSpan + 1;
if (0 <= i && i < rowCount) {
if (0 <= j && j < columnCount) {
if (control == grid [i][j]) return data;
}
}
}
return null;
}
protected void layout (Composite composite, boolean flushCache) {
Rectangle rect = composite.getClientArea ();
layout (composite, true, rect.x, rect.y, rect.width, rect.height, flushCache);
}
Point layout (Composite composite, boolean move, int x, int y, int width, int height, boolean flushCache) {
if (numColumns < 1) {
return new Point (marginLeft + marginWidth * 2 + marginRight, marginTop + marginHeight * 2 + marginBottom);
}
Control [] children = composite.getChildren ();
int count = 0;
for (int i=0; i 0) {
if (data.cacheWidth < data.minimumWidth) {
int trim = 0;
//TEMPORARY CODE
if (child instanceof Scrollable) {
Rectangle rect = ((Scrollable) child).computeTrim (0, 0, 0, 0);
trim = rect.width;
} else {
trim = child.getBorderWidth () * 2;
}
data.cacheWidth = data.cacheHeight = SWT.DEFAULT;
data.computeSize (child, Math.max (0, data.minimumWidth - trim), data.heightHint, false);
}
}
if (data.grabExcessVerticalSpace && data.minimumHeight > 0) {
data.cacheHeight = Math.max (data.cacheHeight, data.minimumHeight);
}
}
/* Build the grid */
int row = 0, column = 0, rowCount = 0, columnCount = numColumns;
Control [][] grid = new Control [4] [columnCount];
for (int i=0; i= grid.length) {
Control [][] newGrid = new Control [lastRow + 4] [columnCount];
System.arraycopy (grid, 0, newGrid, 0, grid.length);
grid = newGrid;
}
if (grid [row] == null) {
grid [row] = new Control [columnCount];
}
while (column < columnCount && grid [row] [column] != null) {
column++;
}
int endCount = column + hSpan;
if (endCount <= columnCount) {
int index = column;
while (index < endCount && grid [row] [index] == null) {
index++;
}
if (index == endCount) break;
column = index;
}
if (column + hSpan >= columnCount) {
column = 0;
row++;
}
}
for (int j=0; j 1) {
int spanWidth = 0, spanMinWidth = 0, spanExpandCount = 0;
for (int k=0; k 0) {
if (makeColumnsEqualWidth) {
int equalWidth = (w + spanWidth) / hSpan;
int remainder = (w + spanWidth) % hSpan, last = -1;
for (int k = 0; k < hSpan; k++) {
widths [last=j-k] = Math.max (equalWidth, widths [j-k]);
}
if (last > -1) widths [last] += remainder;
} else {
if (spanExpandCount == 0) {
widths [j] += w;
} else {
int delta = w / spanExpandCount;
int remainder = w % spanExpandCount, last = -1;
for (int k = 0; k < hSpan; k++) {
if (expandColumn [j-k]) {
widths [last=j-k] += delta;
}
}
if (last > -1) widths [last] += remainder;
}
}
}
if (!data.grabExcessHorizontalSpace || data.minimumWidth != 0) {
w = !data.grabExcessHorizontalSpace || data.minimumWidth == SWT.DEFAULT ? data.cacheWidth : data.minimumWidth;
w += data.horizontalIndent - spanMinWidth - (hSpan - 1) * horizontalSpacing;
if (w > 0) {
if (spanExpandCount == 0) {
minWidths [j] += w;
} else {
int delta = w / spanExpandCount;
int remainder = w % spanExpandCount, last = -1;
for (int k = 0; k < hSpan; k++) {
if (expandColumn [j-k]) {
minWidths [last=j-k] += delta;
}
}
if (last > -1) minWidths [last] += remainder;
}
}
}
}
}
}
}
if (makeColumnsEqualWidth) {
int minColumnWidth = 0;
int columnWidth = 0;
for (int i=0; i 0;
widths [i] = columnWidth;
}
} else {
if (width != SWT.DEFAULT && expandCount > 0) {
int totalWidth = 0;
for (int i=0; i minWidths [j]) {
widths [last = j] = widths [j] + delta;
} else {
widths [j] = minWidths [j];
expandColumn [j] = false;
c--;
}
}
}
if (last > -1) widths [last] += remainder;
for (int j=0; j 1) {
if (!data.grabExcessHorizontalSpace || data.minimumWidth != 0) {
int spanWidth = 0, spanExpandCount = 0;
for (int k=0; k 0) {
if (spanExpandCount == 0) {
widths [j] += w;
} else {
int delta2 = w / spanExpandCount;
int remainder2 = w % spanExpandCount, last2 = -1;
for (int k = 0; k < hSpan; k++) {
if (expandColumn [j-k]) {
widths [last2=j-k] += delta2;
}
}
if (last2 > -1) widths [last2] += remainder2;
}
}
}
}
}
}
}
if (c == 0) break;
totalWidth = 0;
for (int i=0; i currentWidth)) {
int trim = 0;
if (child instanceof Scrollable) {
Rectangle rect = ((Scrollable) child).computeTrim (0, 0, 0, 0);
trim = rect.width;
} else {
trim = child.getBorderWidth () * 2;
}
data.cacheWidth = data.cacheHeight = SWT.DEFAULT;
data.computeSize (child, Math.max (0, currentWidth - trim), data.heightHint, false);
if (data.grabExcessVerticalSpace && data.minimumHeight > 0) {
data.cacheHeight = Math.max (data.cacheHeight, data.minimumHeight);
}
if (flush == null) flush = new GridData [count];
flush [flushLength++] = data;
}
}
}
}
}
}
/* Row heights */
int availableHeight = height - verticalSpacing * (rowCount - 1) - (marginTop + marginHeight * 2 + marginBottom);
expandCount = 0;
int [] heights = new int [rowCount];
int [] minHeights = new int [rowCount];
boolean [] expandRow = new boolean [rowCount];
for (int i=0; i 1) {
int spanHeight = 0, spanMinHeight = 0, spanExpandCount = 0;
for (int k=0; k 0) {
if (spanExpandCount == 0) {
heights [i] += h;
} else {
int delta = h / spanExpandCount;
int remainder = h % spanExpandCount, last = -1;
for (int k = 0; k < vSpan; k++) {
if (expandRow [i-k]) {
heights [last=i-k] += delta;
}
}
if (last > -1) heights [last] += remainder;
}
}
if (!data.grabExcessVerticalSpace || data.minimumHeight != 0) {
h = !data.grabExcessVerticalSpace || data.minimumHeight == SWT.DEFAULT ? data.cacheHeight : data.minimumHeight;
h += data.verticalIndent - spanMinHeight - (vSpan - 1) * verticalSpacing;
if (h > 0) {
if (spanExpandCount == 0) {
minHeights [i] += h;
} else {
int delta = h / spanExpandCount;
int remainder = h % spanExpandCount, last = -1;
for (int k = 0; k < vSpan; k++) {
if (expandRow [i-k]) {
minHeights [last=i-k] += delta;
}
}
if (last > -1) minHeights [last] += remainder;
}
}
}
}
}
}
}
if (height != SWT.DEFAULT && expandCount > 0) {
int totalHeight = 0;
for (int i=0; i minHeights [i]) {
heights [last = i] = heights [i] + delta;
} else {
heights [i] = minHeights [i];
expandRow [i] = false;
c--;
}
}
}
if (last > -1) heights [last] += remainder;
for (int i=0; i 1) {
if (!data.grabExcessVerticalSpace || data.minimumHeight != 0) {
int spanHeight = 0, spanExpandCount = 0;
for (int k=0; k 0) {
if (spanExpandCount == 0) {
heights [i] += h;
} else {
int delta2 = h / spanExpandCount;
int remainder2 = h % spanExpandCount, last2 = -1;
for (int k = 0; k < vSpan; k++) {
if (expandRow [i-k]) {
heights [last2=i-k] += delta2;
}
}
if (last2 > -1) heights [last2] += remainder2;
}
}
}
}
}
}
}
if (c == 0) break;
totalHeight = 0;
for (int i=0; i