在 GWT 2.5 中引入了 RC CellTableBuilder API，但还没有全面的文档可用。是否有任何使用 CellTableBuilder 实现按需自定义行构建的教程\示例？到目前为止，我发现的唯一示例是http://showcase2.jlabanca-testing.appspot.com/#!CwCustomDataGrid但对我来说很困惑。
因此，我的目标是创建包含小部件的额外行，该小部件提供有关表中单击行的详细信息。
问问题
3984 次
2 回答
6
我找到了适合这个问题的解决方案。这是代码示例：
public class CustomCellTableBuilder extends AbstractCellTableBuilder<Object>{
//here go fields, ctor etc.
//ids of elements which details we are going to show
private Set elements;
@Override
protected void buildRowImpl(Object rowValue, int absRowIndex){
//building main rows logic
if(elements.contains(absRowIndex)){
buildExtraRow(absRowIndex, rowValue);
elements.add(absRowIndex);
}
}
private void buildExtraRow(int index, Object rowValue){
TableRowBuilder row = startRow();
TableCellBuilder td = row.startTD().colSpan(getColumns().size());
DivBuilder div = td.startDiv();
Widget widget = new Widget();
//update widget state and appearance here depending on rowValue
div.html(SafeHtmlUtils.fromTrustedString(widget.getElement().getInnerHTML()));
div.end();
td.endTD();
row.endTR();
}}
应该提到的是，当您处理一些导致出现额外行的事件时，您应该在附加到 TableBuilder 的 CellTable 上调用 redrawRaw(rowIndex)。在此调用之前，需要将目标行 ID 添加到元素集。
希望这会有所帮助。
于 2012-07-06T11:02:01.573 回答
0
我创建了这个类来扩展 GWT 中的行。它需要一个您想要扩展的列，并将其替换为可以具有 2 个状态的占位符。
我这样使用它：
PlaceHolderColumn<Notification, SafeHtml> placeholder = new PlaceHolderColumn<Notification, SafeHtml>(new SafeHtmlCell()) {
@Override
public SafeHtml getValue(Notification object) {
return SafeHtmlUtils.fromSafeConstant(getSelected() ? "<i class=\"glyphicon glyphicon-chevron-down\"></i>"
: "<i class=\"glyphicon glyphicon-chevron-right\"></i>");
}
};
notificationsTable.setTableBuilder(new ExpandableCellTableBuilder<Notification, SafeHtml>(notificationsTable, columnBody, placeholder));
我可以访问 glyphicon，所以我使用它们而不是默认占位符列，即 +/-
<这里的图片...但是由于缺乏声誉:( >
columnBody在上面的代码示例中只是一个标准列，它将跨越表格的宽度。占位符将显示在其columnBody配置为坐在的任何位置的位置。
希望对某人有所帮助:)
public class ExpandableCellTableBuilder<T, U> extends AbstractCellTableBuilder<T> {
private Column<T, U> expandColumn = null;
private PlaceHolderColumn<T, ?> placeholderColumn = null;
private final String evenRowStyle;
private final String oddRowStyle;
private final String selectedRowStyle;
private final String cellStyle;
private final String evenCellStyle;
private final String oddCellStyle;
private final String firstColumnStyle;
private final String lastColumnStyle;
private final String selectedCellStyle;
public static class ExpandMultiSelectionModel<T> extends AbstractSelectionModel<T> {
Map<Object, T> selected = new HashMap<Object, T>();
/**
* @param keyProvider
*/
public ExpandMultiSelectionModel(ProvidesKey<T> keyProvider) {
super(keyProvider);
}
/*
* (non-Javadoc)
*
* @see com.google.gwt.view.client.SelectionModel#isSelected(java.lang.Object)
*/
@Override
public boolean isSelected(T object) {
return isKeySelected(getKey(object));
}
protected boolean isKeySelected(Object key) {
return selected.get(key) != null;
}
/*
* (non-Javadoc)
*
* @see com.google.gwt.view.client.SelectionModel#setSelected(java.lang.Object, boolean)
*/
@Override
public void setSelected(T object, boolean selected) {
Object key = getKey(object);
if (isKeySelected(key)) {
this.selected.remove(key);
} else {
this.selected.put(key, object);
}
scheduleSelectionChangeEvent();
}
}
public static abstract class PlaceHolderColumn<T, C> extends Column<T, C> {
private boolean isSelected;
/**
* @param cell
*/
public PlaceHolderColumn(Cell<C> cell) {
super(cell);
}
protected boolean getSelected() {
return isSelected;
}
}
private int expandColumnIndex;
public ExpandableCellTableBuilder(AbstractCellTable<T> cellTable, Column<T, U> expandColumn) {
this(cellTable, expandColumn, new ExpandMultiSelectionModel<T>(cellTable.getKeyProvider()), null);
}
public ExpandableCellTableBuilder(AbstractCellTable<T> cellTable, Column<T, U> exandColumn, SelectionModel<T> selectionModel) {
this(cellTable, exandColumn, selectionModel, null);
}
public ExpandableCellTableBuilder(AbstractCellTable<T> cellTable, Column<T, U> exandColumn, PlaceHolderColumn<T, ?> placeHolder) {
this(cellTable, exandColumn, new ExpandMultiSelectionModel<T>(cellTable.getKeyProvider()), placeHolder);
}
/**
* @param cellTable
* @param columnBody
*/
public ExpandableCellTableBuilder(AbstractCellTable<T> cellTable, Column<T, U> expandColumn, SelectionModel<T> selectionModel,
PlaceHolderColumn<T, ?> placeHolder) {
super(cellTable);
this.expandColumn = expandColumn;
this.cellTable.setSelectionModel(selectionModel);
if (placeHolder == null) {
this.placeholderColumn = new PlaceHolderColumn<T, String>(new TextCell()) {
@Override
public String getValue(T object) {
return getSelected() ? "-" : "+";
}
};
} else {
this.placeholderColumn = placeHolder;
}
// Cache styles for faster access.
Style style = cellTable.getResources().style();
evenRowStyle = style.evenRow();
oddRowStyle = style.oddRow();
selectedRowStyle = " " + style.selectedRow();
cellStyle = style.cell();
evenCellStyle = " " + style.evenRowCell();
oddCellStyle = " " + style.oddRowCell();
firstColumnStyle = " " + style.firstColumn();
lastColumnStyle = " " + style.lastColumn();
selectedCellStyle = " " + style.selectedRowCell();
}
/*
* (non-Javadoc)
*
* @see com.google.gwt.user.cellview.client.AbstractCellTableBuilder#buildRowImpl(java.lang.Object, int)
*/
@Override
protected void buildRowImpl(T rowValue, int absRowIndex) {
// Calculate the row styles.
SelectionModel<? super T> selectionModel = cellTable.getSelectionModel();
final boolean isSelected = (selectionModel == null || rowValue == null) ? false : selectionModel.isSelected(rowValue);
boolean isEven = absRowIndex % 2 == 0;
StringBuilder trClasses = new StringBuilder(isEven ? evenRowStyle : oddRowStyle);
if (isSelected) {
trClasses.append(selectedRowStyle);
}
// Add custom row styles.
RowStyles<T> rowStyles = cellTable.getRowStyles();
if (rowStyles != null) {
String extraRowStyles = rowStyles.getStyleNames(rowValue, absRowIndex);
if (extraRowStyles != null) {
trClasses.append(" ").append(extraRowStyles);
}
}
// Build the row.
TableRowBuilder tr = startRow();
tr.className(trClasses.toString());
// Build the columns.
int columnCount = cellTable.getColumnCount();
for (int curColumn = 0; curColumn < columnCount; curColumn++) {
Column<T, ?> column = cellTable.getColumn(curColumn);
if (column == expandColumn) {
expandColumnIndex = curColumn;
column = placeholderColumn;
placeholderColumn.isSelected = isSelected;
}
// Create the cell styles.
StringBuilder tdClasses = new StringBuilder(cellStyle);
tdClasses.append(isEven ? evenCellStyle : oddCellStyle);
if (curColumn == 0) {
tdClasses.append(firstColumnStyle);
}
if (isSelected) {
tdClasses.append(selectedCellStyle);
}
// The first and last column could be the same column.
if (curColumn == columnCount - 1) {
tdClasses.append(lastColumnStyle);
}
// Add class names specific to the cell.
Context context = new Context(absRowIndex, curColumn, cellTable.getValueKey(rowValue));
String cellStyles = column.getCellStyleNames(context, rowValue);
if (cellStyles != null) {
tdClasses.append(" " + cellStyles);
}
// Build the cell.
HorizontalAlignmentConstant hAlign = column.getHorizontalAlignment();
VerticalAlignmentConstant vAlign = column.getVerticalAlignment();
TableCellBuilder td = tr.startTD();
td.className(tdClasses.toString());
if (hAlign != null) {
td.align(hAlign.getTextAlignString());
}
if (vAlign != null) {
td.vAlign(vAlign.getVerticalAlignString());
}
// Add the inner div.
DivBuilder div = td.startDiv();
div.style().outlineStyle(OutlineStyle.NONE).endStyle();
// Render the cell into the div.
renderCell(div, context, column, rowValue);
// End the cell.
div.endDiv();
td.endTD();
}
// End the row.
tr.endTR();
if (isSelected) {
buildExpandedRow(rowValue, absRowIndex, columnCount, trClasses, isEven, isSelected);
}
}
/**
* @param trClasses
*
*/
private void buildExpandedRow(T rowValue, int absRowIndex, int columnCount, StringBuilder trClasses, boolean isEven, boolean isSelected) {
TableRowBuilder tr = startRow();
tr.className(trClasses.toString());
Column<T, ?> column = expandColumn;
// Create the cell styles.
StringBuilder tdClasses = new StringBuilder(cellStyle);
tdClasses.append(isEven ? evenCellStyle : oddCellStyle);
tdClasses.append(firstColumnStyle);
if (isSelected) {
tdClasses.append(selectedCellStyle);
}
tdClasses.append(lastColumnStyle);
// Add class names specific to the cell.
Context context = new Context(absRowIndex, expandColumnIndex, cellTable.getValueKey(rowValue));
String cellStyles = column.getCellStyleNames(context, rowValue);
if (cellStyles != null) {
tdClasses.append(" " + cellStyles);
}
// Build the cell.
HorizontalAlignmentConstant hAlign = column.getHorizontalAlignment();
VerticalAlignmentConstant vAlign = column.getVerticalAlignment();
TableCellBuilder td = tr.startTD();
td.colSpan(columnCount);
td.className(tdClasses.toString());
if (hAlign != null) {
td.align(hAlign.getTextAlignString());
}
if (vAlign != null) {
td.vAlign(vAlign.getVerticalAlignString());
}
// Add the inner div.
DivBuilder div = td.startDiv();
div.style().outlineStyle(OutlineStyle.NONE).endStyle();
// Render the cell into the div.
renderCell(div, context, column, rowValue);
// End the cell.
div.endDiv();
td.endTD();
// End the row.
tr.endTR();
}
于 2014-12-16T23:31:08.540 回答