Package com.google.gwt.user.client.ui

Class StackPanel

java.lang.Object
com.google.gwt.user.client.ui.UIObject
com.google.gwt.user.client.ui.Widget
com.google.gwt.user.client.ui.Panel
com.google.gwt.user.client.ui.ComplexPanel
com.google.gwt.user.client.ui.StackPanel
All Implemented Interfaces:
HasAttachHandlers, HasHandlers, EventListener, HasVisibility, HasWidgets, HasWidgets.ForIsWidget, IndexedPanel, IndexedPanel.ForIsWidget, InsertPanel, InsertPanel.ForIsWidget, IsWidget, Iterable<Widget>
Direct Known Subclasses:
DecoratedStackPanel
public class StackPanel extends ComplexPanel implements InsertPanel.ForIsWidget
A panel that stacks its children vertically, displaying only one at a time, with a header for each child which the user can click to display.

This widget will only work in quirks mode. If your application is in Standards Mode, use StackLayoutPanel instead.

CSS Style Rules

  • .gwt-StackPanel { the panel itself }
  • .gwt-StackPanel .gwt-StackPanelItem { unselected items }
  • .gwt-StackPanel .gwt-StackPanelItem-selected { selected items }
  • .gwt-StackPanel .gwt-StackPanelContent { the wrapper around the contents of the item }

Example

public class StackPanelExample implements EntryPoint {

  public void onModuleLoad() {
    // Create a stack panel containing three labels.
    StackPanel panel = new StackPanel();
    panel.add(new Label("Foo"), "foo");
    panel.add(new Label("Bar"), "bar");
    panel.add(new Label("Baz"), "baz");

    // Add it to the root panel.
    RootPanel.get().add(panel);
  }
}

See Also:

  • Constructor Details

    • StackPanel

      public StackPanel()
      Creates an empty stack panel.

  • Method Details

    • add

      public void add(Widget w)
      Description copied from class: Panel
      Adds a child widget.

      How to Override this Method

      There are several important things that must take place in the correct order to properly add or insert a Widget to a Panel. Not all of these steps will be relevant to every Panel, but all of the steps must be considered.

      1. Validate: Perform any sanity checks to ensure the Panel can accept a new Widget. Examples: checking for a valid index on insertion; checking that the Panel is not full if there is a max capacity.
      2. Adjust for Reinsertion: Some Panels need to handle the case where the Widget is already a child of this Panel. Example: when performing a reinsert, the index might need to be adjusted to account for the Widget's removal. See ComplexPanel.adjustIndex(Widget, int).
      3. Detach Child: Remove the Widget from its existing parent, if any. Most Panels will simply call Widget.removeFromParent() on the Widget.
      4. Logical Attach: Any state variables of the Panel should be updated to reflect the addition of the new Widget. Example: the Widget is added to the Panel's WidgetCollection at the appropriate index.
      5. Physical Attach: The Widget's Element must be physically attached to the Panel's Element, either directly or indirectly.
      6. Adopt: Call Panel.adopt(Widget) to finalize the add as the very last step.

      Specified by:
      add in interface HasWidgets
      Specified by:
      add in interface InsertPanel
      Overrides:
      add in class Panel
      Parameters:
      w - the widget to be added
      See Also:

    • add

      public void add(Widget w, String stackText)
      Adds a new child with the given widget and header.
      Parameters:
      w - the widget to be added
      stackText - the header text associated with this widget

    • add

      public void add(Widget w, SafeHtml stackHtml)
      Adds a new child with the given widget and header, optionally interpreting the header as HTML.
      Parameters:
      w - the widget to be added
      stackHtml - the header html associated with this widget

    • add

      public void add(Widget w, String stackText, boolean asHTML)
      Adds a new child with the given widget and header, optionally interpreting the header as HTML.
      Parameters:
      w - the widget to be added
      stackText - the header text associated with this widget
      asHTML - true to treat the specified text as HTML

    • getSelectedIndex

      public int getSelectedIndex()
      Gets the currently selected child index.
      Returns:
      selected child

    • insert

      public void insert(IsWidget w, int beforeIndex)
      Specified by:
      insert in interface InsertPanel.ForIsWidget

    • insert

      public void insert(Widget w, int beforeIndex)
      Description copied from interface: InsertPanel
      Inserts a child widget before the specified index. If the widget is already a child of this panel, it will be moved to the specified index.
      Specified by:
      insert in interface InsertPanel
      Parameters:
      w - the child widget to be inserted
      beforeIndex - the index before which it will be inserted

    • onBrowserEvent

      public void onBrowserEvent(Event event)
      Description copied from interface: EventListener
      Fired whenever a browser event is received.
      Specified by:
      onBrowserEvent in interface EventListener
      Overrides:
      onBrowserEvent in class Widget
      Parameters:
      event - the event received

    • remove

      public boolean remove(int index)
      Description copied from interface: IndexedPanel
      Removes the widget at the specified index.
      Specified by:
      remove in interface IndexedPanel
      Overrides:
      remove in class ComplexPanel
      Parameters:
      index - the index of the widget to be removed
      Returns:
      false if the widget is not present

    • remove

      public boolean remove(Widget child)
      Description copied from class: Panel
      Removes a child widget.

      How to Override this Method

      There are several important things that must take place in the correct order to properly remove a Widget from a Panel. Not all of these steps will be relevant to every Panel, but all of the steps must be considered.

      1. Validate: Make sure this Panel is actually the parent of the child Widget; return false if it is not.
      2. Orphan: Call Panel.orphan(Widget) first while the child Widget is still attached.
      3. Physical Detach: Adjust the DOM to account for the removal of the child Widget. The Widget's Element must be physically removed from the DOM.
      4. Logical Detach: Update the Panel's state variables to reflect the removal of the child Widget. Example: the Widget is removed from the Panel's WidgetCollection.

      Specified by:
      remove in interface HasWidgets
      Overrides:
      remove in class ComplexPanel
      Parameters:
      child - the widget to be removed
      Returns:
      true if the child was present

    • setStackText

      public void setStackText(int index, String text)
      Sets the text associated with a child by its index.
      Parameters:
      index - the index of the child whose text is to be set
      text - the text to be associated with it

    • setStackText

      public void setStackText(int index, SafeHtml html)
      Sets the html associated with a child by its index.
      Parameters:
      index - the index of the child whose text is to be set
      html - the html to be associated with it

    • setStackText

      public void setStackText(int index, String text, boolean asHTML)
      Sets the text associated with a child by its index.
      Parameters:
      index - the index of the child whose text is to be set
      text - the text to be associated with it
      asHTML - true to treat the specified text as HTML

    • showStack

      public void showStack(int index)
      Shows the widget at the specified child index.
      Parameters:
      index - the index of the child to be shown

    • onEnsureDebugId

      protected void onEnsureDebugId(String baseID)
      Affected Elements:
      • -text# = The element around the header at the specified index.
      • -text-wrapper# = The element around the header at the specified index.
      • -content# = The element around the body at the specified index.
      Overrides:
      onEnsureDebugId in class UIObject
      Parameters:
      baseID - the base ID used by the main element
      See Also:

    • createHeaderElem

      Element createHeaderElem()
      Returns a header element.

    • getHeaderTextElem

      Element getHeaderTextElem(Element headerElem)
      Get the element that holds the header text given the header element created by #createHeaderElement.
      Parameters:
      headerElem - the header element
      Returns:
      the element around the header text

    • addHeaderStyleName

      public void addHeaderStyleName(int index, String styleName)
      Adds the styleName on the <tr> for the header specified by index.
      Parameters:
      index - the index of the header row to apply to the style to
      styleName - the name of the class to add

    • removeHeaderStyleName

      public void removeHeaderStyleName(int index, String styleName)
      Removes the styleName off the <tr> for the header specified by index.
      Parameters:
      index - the index of the header row to remove the style from
      styleName - the name of the class to remove