Gwt 如何在listgrid的单元格中拖放元素？

我正在使用：SmartGwt 3.0；gwt 2.4；firefox 11和Google Chrome 19.0.1084.52

首先我想为我的英语道歉，因为它很糟糕。 我需要的是在listgrid的单元格中拖放组件（例如标签、图像等）。 我知道可以拖动记录，但我想在单元格中添加任何类型的组件。 感谢您的帮助，无论帮助有多小，否则我将创建一个表组件，其中包含大量的属性listgrid，您可以在单元格中添加一个组件。事实并非如此

我使用的是smartgwt的最新版本

我正在试验“getShowRecordComponents”、“getShowRecordComponentsByCell”、“WillAcceptDrop”和“CreateRecordComponent”方法。我必须拖放一个组件smartgwt（通过先前的配置），但我在记录的末尾拖了一段时间，我希望您将它放在您拖放组件的列行中

这个类在另一个类的内部调用

private class CustomList extends ListGrid{
    //record que hace el drop
    private ListGridRecord currentRecord = null;
    //elemento que se va a dropear
    private Canvas currentCanvas = null;

    //private int index;

public CustomList() {
    this.setHeight(400);
    this.setWidth(400);
    this.setCanResizeFields(true);
    this.setResizeFieldsInRealTime(true);
    this.setShowRecordComponentsByCell(true);
    this.setShowRecordComponents(true);      
    this.setCanAcceptDrop(true);          

    this.addRecordDropHandler(new RecordDropHandler() {

      @Override
      public void onRecordDrop(RecordDropEvent event) {
          System.out.println("X: " + event.getX());
          System.out.println("Y: " + event.getY());
          System.out.println("index: " + event.getIndex());
          System.out.println("event.getDropRecords() ==>  "+ event.getDropRecords());
          //guardamo el record y el canvas que se hace el drop
          currentRecord = event.getTargetRecord();
          currentCanvas = EventHandler.getDragTarget();
       }
     });
    //defino columna ico
    ListGridField field = new ListGridField("icon");
    ListGridField field2 = new ListGridField("valor");
    this.setFields(field, field2);

    //añado record para poder aceptar drops
    ListGridRecord record = new ListGridRecord();
    ListGridRecord record2 = new ListGridRecord();
    record.setCanAcceptDrop(true);
    record.setAttribute("icon", "Hola"); 
    record.setAttribute("valor", "adios");
    record2.setAttribute("icon", "Segundo"); 
    record2.setAttribute("valor", "Segundo Adios");
    this.addData(record);
    this.addData(record2);
  }

  //la llamada a createRecordComponent la hace el listgrid al crearse.
  @Override
  protected Canvas createRecordComponent (ListGridRecord record, Integer colNum) {

    System.out.println("record: " + record);
    System.out.println("colNum: " + colNum);
    System.out.println("currentRecord: " + currentRecord);

    if (record.equals(currentRecord)) {
      System.out.println("createRecordComponent - REGRESARA: " + currentCanvas);

      return currentCanvas;
    }

    return null;
  }

  @Override
  public Boolean willAcceptDrop(){
    return true;
  }

  @Override
  public Canvas updateRecordComponent (ListGridRecord record, Integer colNum, Canvas component, boolean recordChange) {
    System.out.println("***************************************************************************************");
    System.out.println("Estoy en gridView");
    System.out.println("***************************************************************************************");
    System.out.println("record es : "+record);
    System.out.println("colNum es : "+colNum);
    System.out.println("component es : "+component);
    System.out.println("recordChange es :"+recordChange);
   System.out.println("***************************************************************************************");
    return component;
  }
}

---

你能帮我吗？

我继续研究，并设法在listgrid的单元格中插入其他小部件，尽管我根本没有设法配置它，因此向任何知道正确方法的人寻求帮助。 1.-SmartGWT版本：

SmartClient版本：SC_SNAPSHOT-2011-12-05/仅限LGPL开发（2011-12-05版）

2.-浏览器版本：

VersGoogle Chrome 19.0.1084.52 m和Firefox 11.0

3.问题： 如果设置为true，则此listGrid应在网格的每一行中创建并显示嵌入式组件。 使用此功能的开发人员应该实现ListGrid.createRecordComponent和ListGrid.updateRecordComponent方法，但是调用方法“updateRecordComponent”，但是调用此方法只是因为我从“createRecordComponent”调用它。为什么会有这种行为

每次运行“createRecordComponent”方法时，都会创建一个新行，为什么要这样做？我只想在一个单元格列表网格中做一个下降

4.代码：

private class CustomList extends ListGrid{
    //record que hace el drop
    private ListGridRecord currentRecord = null;
    private ListGridRecord[] listRecord;
    //elemento que se va a dropear
    private Canvas currentCanvas = null;
    private EmbeddedPosition position;
//posiciones offset respecto a diferentes indices.
    private int x, x1, x2;
    private int y, y1, y2;      
    private int col, fil;


  public CustomList() {
    this.setHeight(400);
    this.setWidth(400); 
    this.setCanResizeFields(true);
    this.setResizeFieldsInRealTime(true);
    this.setRecordComponentPoolingMode(RecordComponentPoolingMode.RECYCLE);
    this.setRecordComponentPosition(EmbeddedPosition.EXPAND);
    this.setCanResizeFields(true);
    this.setShowRecordComponentsByCell(true);
    this.setShowRecordComponents(true);      
    this.setCanAcceptDrop(true);
    this.setCanReorderRecords(true);
    this.setCanAcceptDroppedRecords(true);
    this.setCanDrop(true);
   
    this.addRecordDropHandler(new RecordDropHandler() {
    
    @Override
    public void onRecordDrop(RecordDropEvent event) {
      //guardamo el record y el canvas que se hace el drop
      listRecord = event.getDropRecords();          
      currentRecord = event.getTargetRecord();
      currentCanvas = EventHandler.getDragTarget();
      position = getRecordComponentPosition();          
      x=event.getX();
      y=event.getY();          
      col=getEventColumn();
      fil=getEventRow();         
    }
  });
  
  //defino columna ico y valor
  ListGridField field = new ListGridField("icon");
  ListGridField field2 = new ListGridField("valor");
  this.setFields(field, field2);
  
  //añado record para poder aceptar drops
  ListGridRecord record = new ListGridRecord();
  ListGridRecord record2 = new ListGridRecord();
  record.setCanAcceptDrop(true);
  record.setAttribute("icon", "Hola"); 
  record.setAttribute("valor", "adios");
  record2.setAttribute("icon", "Segundo"); 
  record2.setAttribute("valor", "Segundo Adios");
  this.addData(record);
  this.addData(record2);
}

//la llamada createRecordComponent ,debería hacersela al crearse.
@Override
protected Canvas createRecordComponent (ListGridRecord record, Integer colNum) {
//como comprueba, porque setShowRecordComponentsByCell está a true, celda por celda, me quedo para actualizar solo cuando coincide
//la fila y la columna en la que he hecho el drop.
  if (record.equals(currentRecord) && (colNum.equals(col))) {
    updateRecordComponent(currentRecord,colNum,currentCanvas, true);
  }
  return null;
}

@Override
public Boolean willAcceptDrop(){
  return true;
}

@Override
public Canvas updateRecordComponent (ListGridRecord record, Integer colNum, Canvas component, boolean recordChange) {
  x1=this.getAbsoluteLeft();
  y1=this.getAbsoluteTop();
  x2 = component.getAbsoluteLeft();
  y2 = component.getAbsoluteTop();
  //currentCanvas.setSnapTo("C");
  addEmbeddedComponent(component, record, fil, colNum, EmbeddedPosition.WITHIN);      
  
  return component;
}

}