Package com.google.gwt.user.cellview.client

Class Header<H>

java.lang.Object
com.google.gwt.user.cellview.client.Header<H>
Type Parameters:
H - the Cell type
Direct Known Subclasses:
SafeHtmlHeader, TextHeader
public abstract class Header<H> extends Object
A table column header or footer.

  • Constructor Details

    • Header

      public Header(Cell<H> cell)
      Construct a Header with a given Cell.
      Parameters:
      cell - the Cell responsible for rendering items in the header

  • Method Details

    • getCell

      public Cell<H> getCell()
      Return the Cell responsible for rendering items in the header.
      Returns:
      the header Cell

    • getHeaderStyleNames

      public String getHeaderStyleNames()
      Get extra style names that should be applied to a cell in this header. May be overridden to get value dependent styles by calling getValue().
      Returns:
      the extra styles of the given row in a space-separated list, or null if there are no extra styles for the cells in this header

    • getKey

      public Object getKey()
      Get the key for the header value. By default, the key is the same as the value. Override this method to return a custom key.
      Returns:
      the key associated with the value

    • getValue

      public abstract H getValue()
      Return the header value.
      Returns:
      the header value

    • onBrowserEvent

      public void onBrowserEvent(Cell.Context context, Element elem, NativeEvent event)
      Handle a browser event that took place within the header.
      Parameters:
      context - the context of the header
      elem - the parent Element
      event - the native browser event

    • onPreviewColumnSortEvent

      public boolean onPreviewColumnSortEvent(Cell.Context context, Element elem, NativeEvent event)
      Preview a browser event that may trigger a column sort event. Return true if the CellTable should proceed with sorting the column. Subclasses can override this method to disable column sort for some click events, or particular header/footer sections.

      This method will be invoked even if the header's cell does not consume a click event.

      Parameters:
      context - the context of the header
      elem - the parent Element
      event - the native browser event
      Returns:
      true if the CellTable should continue respond to the event (i.e., if this is a click event on a sortable column's header, fire ColumnSortEvent). False if the CellTable should stop respond to the event.

    • render

      public void render(Cell.Context context, SafeHtmlBuilder sb)
      Render the header.
      Parameters:
      context - the context of the header
      sb - a SafeHtmlBuilder to render into

    • setHeaderStyleNames

      public void setHeaderStyleNames(String styleNames)
      Set extra style names that should be applied to every cell in this header.

      If you want to apply style names based on the header value, override

      invalid reference 
      #getHeaderStyleNames(Object)
      directly.

      Parameters:
      styleNames - the extra style names to apply in a space-separated list, or null if there are no extra styles for this cell

    • setUpdater

      public void setUpdater(ValueUpdater<H> updater)
      Set the ValueUpdater.
      Parameters:
      updater - the value updater to use