这几天，因项目的需要。要在GXT中实现一个Grid，带PagingToolbar和CheckBoxColumn 。最重要的是这个Grid，访问的数据表，是其他用户定义的，在访问的时候不知道表的数据结构。所以，前端展示面临动态生成ColumnModel 的问题。查询GXT的事例发现所有的例子都是如下定义ColumnConfig：
ColumnConfig<Post, String> forumColumn = new ColumnConfig<Post, String>(properties.forum(), 150, "Forum"); ColumnConfig<Post, String> usernameColumn = new ColumnConfig<Post, String>(properties.username(), 150, "Username"); ColumnConfig<Post, String> subjectColumn = new ColumnConfig<Post, String>(properties.subject(), 150, "Subject"); ColumnConfig<Post, Date> dateColumn = new ColumnConfig<Post, Date>(properties.date(), 150, "Date");
这里的Post 是一个已知的数据结构。这里不可能先给出一个确定的数据结构。怎么办？
我这里用了一个ColumnValueProvider 和 Row对象来实现这个动态的数据结构。
public static class Row
{
private static int nextId;
private final Map<String,String> columnsMap;
private final String key = "Row" + Integer.toString(nextId++);
public Row() {
columnsMap = new HashMap<String, String>();
}
public String getColumn(String columnName) {
return columnsMap.get(columnName);
}
public String getKey() {
return key;
}
public void setValue(String columnName, String value) {
columnsMap.put(columnName, value);
}
}
/**
* A model key provider that supports a spreadsheet-like table with an arbitrary number of rows.
*/
public class RowKeyProvider implements ModelKeyProvider<Row>
{
@Override
public String getKey(Row row) {
return row.getKey();
}
}
/**
* A value provider that supports a spreadsheet-like table with an arbitrary number of rows.
*/
public class RowValueProvider
{
public ValueProvider<Row, String> getColumnValueProvider(int columnIndex,String columnName) {
return new ColumnValueProvider(columnIndex,columnName);
}
}
public static class ColumnValueProvider implements ValueProvider<Row, String>
{
private static int nextId;
// private final int columnIndex;
private final String columnName;
private final String path = "Column" + Integer.toString(nextId++);
public ColumnValueProvider(int columnIndex, String columnName) {
// this.columnIndex = columnIndex;
this.columnName = columnName;
}
@Override
public String getPath() {
return path;
}
@Override
public String getValue(Row row) {
return row.getColumn(columnName);
}
@Override
public void setValue(Row row, String value) {
row.setValue(columnName, value);
}
}
定义的Grid，且该Grid是一个空Grid：
public void setGridPanel(XmlUtils xmlUtils)
{
final ToolBar headerToolbar = new ToolBar();
headerToolbar.setSpacing(2);
headerToolbar.add(deleteBtn);
headerToolbar.add(addBtn);
pagingToolBar = new PagingToolBar(30);
pagingToolBar.getElement().getStyle().setProperty("borderBottom", "none");
pagingToolBar.setSpacing(2);
String path = "HttpService";
RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, path);
RequestFactoryProxy <TablePagingLoadConfig, PagingLoadResult<Row>> proxy = new RequestFactoryProxy<TablePagingLoadConfig, PagingLoadResult<Row>>() {
@Override
public void load(final TablePagingLoadConfig loadConfig, final Receiver<? super PagingLoadResult<Row>> receiver) {
RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, "HttpService");
HttpProxy<TablePagingLoadConfig> httpProxy = new HttpProxy<TablePagingLoadConfig>(builder);
httpProxy.load(loadConfig, new Callback<String, Throwable>() {
@Override
public void onSuccess(String result) {
XmlUtils xml = new XmlUtils(XMLParser.parse(result));
String statusCode = xml.getStatus().getCode();
if(! statusCode.equals("0000"))
{
String msg = xml.getStatus().getMessage();
String exp = xml.getStatus().getException();
Client.INSTANCE.showErrWin("Error", msg, exp);
return;
}
Element root = xml.getRootElement();
NodeList recordsList = root.getElementsByTagName("records");
Element recordsElement = (Element) recordsList.item(0);
int allCount = Integer.parseInt(recordsElement.getAttribute("allCount"));
int currentCount = Integer.parseInt(recordsElement.getAttribute("currentCount"));
NodeList nodeList = root.getElementsByTagName("record");
List<Row> records = new ArrayList<Row>();
for(int i = 0 ; i < nodeList.getLength() ; i ++)
{
Row row = new Row();
Element record = (Element) nodeList.item(i);
for(int j = 0 ; j < record.getChildNodes().getLength(); j++)
{
Element column = (Element) record.getChildNodes().item(j);
String columnName = column.getAttribute("name");
String columnValue = column.getAttribute("value");
row.setValue(columnName, columnValue);
}
records.add(row);
}
receiver.onSuccess(new PagingLoadResultBean<Row>(records, allCount, loadConfig.getOffset()));
}
@Override
public void onFailure(Throwable reason) {
}
});
}
};
// HttpProxy<TablePagingLoadConfig> httpProxy = new HttpProxy<TablePagingLoadConfig>(builder);
XmlReader<TablePagingLoadResult<Row>, DataCollection> reader = new XmlReader<TablePagingLoadResult<Row>, DataCollection>(
XmlAutoBeanFactory.instance, DataCollection.class) {
// protected PagingLoadResult<Map<String,String>> createReturnData(Object loadConfig, DataCollection records) {
// return new PagingLoadResultBean<Map<String,String>>(records.getValues());
// }
};
IdentityValueProvider<Row> identity = new IdentityValueProvider<Row>();
selectionModel = new CheckBoxSelectionModel<Row>(identity);
loader = new PagingLoader<TablePagingLoadConfig, TablePagingLoadResult<Row>>((DataProxy)proxy);
loader.useLoadConfig(new TablePagingLoadConfig(this));
store = new ListStore<Row>(new RowKeyProvider());
store.setAutoCommit(true);
loader.addLoadHandler(new LoadResultListStoreBinding<TablePagingLoadConfig, Row, TablePagingLoadResult<Row>>(store));
List<ColumnConfig<Row, ?>> l = new ArrayList<ColumnConfig<Row, ?>>();
cm = null;
grid = null;
ValueProvider<Row, String> cvp = rvp.getColumnValueProvider(0,"");
ColumnConfig<Row, String> column = new ColumnConfig<Row, String>(cvp, 100, "NoTitle");
l.add(column);
cm = new ColumnModel<Row>(l);
grid = new Grid<Row>(store, cm);
grid.setSelectionModel(selectionModel);
// grid.getView().setForceFit(true);
grid.setBorders(false);
grid.setLoader(loader);
pagingToolBar.bind(loader);
FramedPanel cp = new FramedPanel();
HorizontalLayoutContainer toolbarPanel = new HorizontalLayoutContainer();
toolbarPanel.setStyleName("toolbarPanel");
toolbarPanel.setHeight(30);
toolbarPanel.setWidth(-1);
toolbarPanel.add(headerToolbar,new HorizontalLayoutData(1, 30, new Margins(0)));
toolbarPanel.add(pagingToolBar,new HorizontalLayoutData(-1, 30, new Margins(0)));
cp.setHeaderVisible(false);
cp.setBorders(false);
cp.setWidth("100%");
cp.setStyleName("gridHeaderPanel");
cp.add(toolbarPanel);
VerticalLayoutContainer verticalLayoutContainer = new VerticalLayoutContainer();
verticalLayoutContainer.setBorders(false);
verticalLayoutContainer.add(cp, new VerticalLayoutData(1, 30, new Margins(-8,0,0,0)));
verticalLayoutContainer.add(grid, new VerticalLayoutData(1, 1));
gridPanel.add(verticalLayoutContainer);
}
生成Grid 的数据结构：
private void refreshGrid(XmlUtils xmlUtils)
{
//TODO: refresh the grid
tableStructure = xmlUtils;
List<ColumnConfig<Row, ?>> l = new ArrayList<ColumnConfig<Row, ?>>();
if(xmlUtils != null)
{
// loader.addLoadHandler(new LoadResultListStoreBinding<PagingLoadConfig, Map<String,String>, PagingLoadResult<Map<String,String>>>(store));
Element respEle = xmlUtils.getResponseElement();
NodeList nodeList = respEle.getElementsByTagName("COLUMN");
l.add(selectionModel.getColumn());
for(int i = 0 ; i < nodeList.getLength(); i++)
{
Element currentElement = (Element) nodeList.item(i);
String COLUMN_NAME = currentElement.getAttribute("COLUMN_NAME");
String DATA_TYPE = currentElement.getAttribute("DATA_TYPE");
String IS_NULLABLE = currentElement.getAttribute("IS_NULLABLE");
String COLUMN_KEY = currentElement.getAttribute("COLUMN_KEY");
String CHARACTER_MAXIMUM_LENGTH = currentElement.getAttribute("CHARACTER_MAXIMUM_LENGTH");
int columnWidth = Integer.parseInt(CHARACTER_MAXIMUM_LENGTH);
ValueProvider<Row, String> cvp = rvp.getColumnValueProvider(i,COLUMN_NAME);
ColumnConfig<Row, String> column = new ColumnConfig<Row, String>(cvp, 100, COLUMN_NAME);
l.add(column);
}
}
cm = new ColumnModel<Row>(l);
if(this.getCurrentTableData().isPersonal())
{
if(rowEditing!=null)
{
rowEditing.setEditableGrid(null);
rowEditing = null;
}
rowEditing = createGridEditing(grid);
}
else
{
if(rowEditing!=null)
{
rowEditing.setEditableGrid(null);
rowEditing = null;
}
}
// rowEditing.addEditor((ColumnConfig<Row,Boolean>)l.get(0), new Label(""));
if(xmlUtils != null)
{
Element respEle = xmlUtils.getResponseElement();
NodeList nodeList = respEle.getElementsByTagName("COLUMN");
// rowEditing.addEditor((selectionModel.getColumn()) l.get(0), new CheckBox());
for(int i = 0; i < nodeList.getLength();i++)
{
Element currentElement = (Element) nodeList.item(i);
String COLUMN_KEY = "";
final int CHARACTER_MAXIMUM_LENGTH = Integer.parseInt(currentElement.getAttribute("CHARACTER_MAXIMUM_LENGTH"));
if(currentElement!=null)
{
COLUMN_KEY = currentElement.getAttribute("COLUMN_KEY");
}
if(this.getCurrentTableData().isPersonal())
{
final TextField tf = new TextField();
tf.addKeyDownHandler(new KeyDownHandler(){
@Override
public void onKeyDown(KeyDownEvent event) {
if(tf.getText().length()>= CHARACTER_MAXIMUM_LENGTH)
{
tf.setText(tf.getText().substring(0,CHARACTER_MAXIMUM_LENGTH - 1));
}
}
});
// tf.addKeyDownHandler(new KeyDownHandler(){
// @Override
// public void KeyDown(Event event) {
// //TODO:Query Submit
//
// }
// });
rowEditing.addEditor((ColumnConfig<Row,String>)l.get(i + 1),tf);
}
}
grid.setLoader(loader);
}
grid.reconfigure(store, cm);
grid.getStore().clear();
}
时间： 2024-10-10 02:03:39