RCP中一个Tableviewer特有的的Layout （TableLayout）的扩展
?? 为了使TableViewer中各列间距相等编写的类，继承自Tablelayout，实现ControlListener 接口。
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package com.unutrip.plugin.dev.commons;import java.util.ArrayList;import java.util.List;import org.eclipse.jface.viewers.ColumnLayoutData;import org.eclipse.jface.viewers.ColumnPixelData;import org.eclipse.jface.viewers.ColumnWeightData;import org.eclipse.jface.viewers.TableLayout;import org.eclipse.swt.events.ControlEvent;import org.eclipse.swt.events.ControlListener;import org.eclipse.swt.widgets.Table;import org.eclipse.swt.widgets.TableColumn;/** * AutoResizeTableLayout layout = new AutoResizeTableLayout(tableRegionListInfo); * * tableRegionListInfo.setLayout(layout); * 其中tableRegionListInfo为需要各列自动充满整个表格的表格（Table） * * 最后在表格中的各列中加上如下代码： *layout.addColumnData(new ColumnWeightData(200)); * 其中200代表此列在表格中所占的比例，例如在另外一列后面设置 * layout.addColumnData(new ColumnWeightData(400));则此列在表格中所占的比例是上一个表格的两倍。 * @author longgangbai * */public class AutoResizeTableLayout extends TableLayout implementsControlListener {private final Table table;private List columns = new ArrayList();private boolean autosizing = false;public AutoResizeTableLayout(Table table) {this.table = table;table.addControlListener(this);}@Overridepublic void addColumnData(ColumnLayoutData data) {columns.add(data);super.addColumnData(data);}public void controlMoved(ControlEvent e) {}public void controlResized(ControlEvent e) {if (autosizing) {return;}autosizing = false;try {autoSizeColumns();} finally {autosizing = false;}}private void autoSizeColumns(){ int width = table.getClientArea().width; // XXX: Layout is being called with an invalid value // the first time it is being called on Linux. // This method resets the layout to null, // so we run it only when the value is OK. if (width <= 1) return; TableColumn[] tableColumns = table.getColumns(); int size = Math.min(columns.size(), tableColumns.length); int[] widths = new int[size]; int fixedWidth = 0; int numberOfWeightColumns = 0; int totalWeight = 0; // First calculate space occupied by fixed columns. for (int i = 0; i < size; i++){ ColumnLayoutData col = (ColumnLayoutData) columns.get(i); if (col instanceof ColumnPixelData){ int pixels = ((ColumnPixelData) col).width; widths[i] = pixels; fixedWidth += pixels; } else if (col instanceof ColumnWeightData){ ColumnWeightData cw = (ColumnWeightData) col; numberOfWeightColumns++; int weight = cw.weight; totalWeight += weight; } else{ throw new IllegalStateException("Unknown column layout data"); } } // Do we have columns that have a weight? if (numberOfWeightColumns > 0){ // Now, distribute the rest // to the columns with weight. int rest = width - fixedWidth; int totalDistributed = 0; for (int i = 0; i < size; i++){ ColumnLayoutData col = (ColumnLayoutData) columns.get(i); if (col instanceof ColumnWeightData) { ColumnWeightData cw = (ColumnWeightData) col; int weight = cw.weight; int pixels = totalWeight == 0 ? 0 : weight * rest / totalWeight; if (pixels < cw.minimumWidth) pixels = cw.minimumWidth; totalDistributed += pixels; widths[i] = pixels; } } // Distribute any remaining pixels // to columns with weight. int diff = rest - totalDistributed; for (int i = 0; diff > 0; i++){ if (i == size) i = 0; ColumnLayoutData col = (ColumnLayoutData) columns.get(i); if (col instanceof ColumnWeightData){ ++widths[i]; --diff; } } } for (int i = 0; i < size; i++){ if (tableColumns[i].getWidth() != widths[i]) tableColumns[i].setWidth(widths[i]); } }}?