com.google.gwt.user.client.ui

## Class TabLayoutPanel

- java.lang.Object
- - com.google.gwt.user.client.ui.UIObject
  - - com.google.gwt.user.client.ui.Widget
    - - com.google.gwt.user.client.ui.Composite
      - - com.google.gwt.user.client.ui.ResizeComposite
        - - com.google.gwt.user.client.ui.TabLayoutPanel

- All Implemented Interfaces:
    HasAttachHandlers, HasBeforeSelectionHandlers<java.lang.Integer>, HasSelectionHandlers<java.lang.Integer>, HasHandlers, EventListener, AnimatedLayout, HasVisibility, HasWidgets, IndexedPanel, IndexedPanel.ForIsWidget, IsRenderable, IsWidget, ProvidesResize, RequiresResize, java.lang.Iterable<Widget>

      public class TabLayoutPanel
      extends ResizeComposite
      implements HasWidgets, ProvidesResize, IndexedPanel.ForIsWidget, AnimatedLayout, HasBeforeSelectionHandlers<java.lang.Integer>, HasSelectionHandlers<java.lang.Integer>

  A panel that represents a tabbed set of pages, each of which contains another widget. Its child widgets are shown as the user selects the various tabs associated with them. The tabs can contain arbitrary text, HTML, or widgets.

  This widget will only work in standards mode, which requires that the HTML page in which it is run have an explicit <!DOCTYPE> declaration.

  ### CSS Style Rules

  .gwt-TabLayoutPanel
    the panel itself
  .gwt-TabLayoutPanel .gwt-TabLayoutPanelTabs
    the tab bar element
  .gwt-TabLayoutPanel .gwt-TabLayoutPanelTab
    an individual tab
  .gwt-TabLayoutPanel .gwt-TabLayoutPanelTabInner
    an element nested in each tab (useful for styling)
  .gwt-TabLayoutPanel .gwt-TabLayoutPanelContent
    applied to all child content widgets

  ### Example

  >     public class TabLayoutPanelExample implements EntryPoint {

  >       public void onModuleLoad() {
  >         // Create a three-item tab panel, with the tab area 1.5em tall.
  >         TabLayoutPanel p = new TabLayoutPanel(1.5, Unit.EM);
  >         p.add(new HTML("this"), "[this]");
  >         p.add(new HTML("that"), "[that]");
  >         p.add(new HTML("the other"), "[the other]");

  >         // Attach the LayoutPanel to the RootLayoutPanel. The latter will listen for
  >         // resize events on the window to ensure that its children are informed of
  >         // possible size changes.
  >         RootLayoutPanel rp = RootLayoutPanel.get();
  >         rp.add(p);
  >       }
  >     }

  ### Use in UiBinder Templates

  A TabLayoutPanel element in a `UiBinder` template must have a `barHeight` attribute with a double value, and may have a `barUnit` attribute with a `Style.Unit` value. `barUnit` defaults to PX.

  The children of a TabLayoutPanel element are laid out in <g:tab> elements. Each tab can have one widget child and one of two types of header elements. A <g:header> element can hold html, or a <g:customHeader> element can hold a widget. (Note that the tags of the header elements are not capitalized. This is meant to signal that the head is not a runtime object, and so cannot have a `ui:field` attribute.)

  For example:

       <g:TabLayoutPanel barUnit='EM' barHeight='3'>
        <g:tab>
          <g:header size='7'><b>HTML</b> header</g:header>
          <g:Label>able</g:Label>
        </g:tab>
        <g:tab>
          <g:customHeader size='7'>
            <g:Label>Custom header</g:Label>
          </g:customHeader>
          <g:Label>baker</g:Label>
        </g:tab>
       </g:TabLayoutPanel>

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class com.google.gwt.user.client.ui.UIObject

      `UIObject.DebugIdImpl, UIObject.DebugIdImplEnabled`

    - ### Nested classes/interfaces inherited from interface com.google.gwt.user.client.ui.HasWidgets

      `HasWidgets.ForIsWidget`

  - ### Field Summary

    - ### Fields inherited from class com.google.gwt.user.client.ui.Widget

      `eventsToSink`

    - ### Fields inherited from class com.google.gwt.user.client.ui.UIObject

      `DEBUG_ID_PREFIX, MISSING_ELEMENT_ERROR, SETELEMENT_TWICE_ERROR`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `TabLayoutPanel(double barHeight, Style.Unit barUnit)` Creates an empty tab panel.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `add(IsWidget w)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `add(IsWidget w, IsWidget tab)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `add(IsWidget w, java.lang.String text)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `add(IsWidget w, java.lang.String text, boolean asHtml)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `add(Widget w)` Adds a child widget.
    `void` | `add(Widget child, SafeHtml html)` Adds a widget to the panel.
    `void` | `add(Widget child, java.lang.String text)` Adds a widget to the panel.
    `void` | `add(Widget child, java.lang.String text, boolean asHtml)` Adds a widget to the panel.
    `void` | `add(Widget child, Widget tab)` Adds a widget to the panel.
    `HandlerRegistration` | `addBeforeSelectionHandler(BeforeSelectionHandler<java.lang.Integer> handler)` Adds a `BeforeSelectionEvent` handler.
    `HandlerRegistration` | `addSelectionHandler(SelectionHandler<java.lang.Integer> handler)` Adds a `SelectionEvent` handler.
    `void` | `animate(int duration)` Layout children, animating over the specified period of time.
    `void` | `animate(int duration, Layout.AnimationCallback callback)` Layout children, animating over the specified period of time.
    `void` | `clear()` Removes all child widgets.
    `void` | `forceLayout()` Layout children immediately.
    `int` | `getAnimationDuration()` Get the duration of the animated transition between tabs.
    `int` | `getSelectedIndex()` Gets the index of the currently-selected tab.
    `Widget` | `getTabWidget(int index)` Gets the widget in the tab at the given index.
    `Widget` | `getTabWidget(IsWidget child)` Convenience overload to allow `IsWidget` to be used directly.
    `Widget` | `getTabWidget(Widget child)` Gets the widget in the tab associated with the given child widget.
    `Widget` | `getWidget(int index)` Returns the widget at the given index.
    `int` | `getWidgetCount()` Returns the number of tabs and widgets.
    `int` | `getWidgetIndex(IsWidget child)` Convenience overload to allow `IsWidget` to be used directly.
    `int` | `getWidgetIndex(Widget child)` Returns the index of the given child, or -1 if it is not a child.
    `void` | `insert(IsWidget child, int beforeIndex)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `insert(IsWidget child, IsWidget tab, int beforeIndex)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `insert(IsWidget child, java.lang.String text, boolean asHtml, int beforeIndex)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `insert(IsWidget child, java.lang.String text, int beforeIndex)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `insert(Widget child, int beforeIndex)` Inserts a widget into the panel.
    `void` | `insert(Widget child, SafeHtml html, int beforeIndex)` Inserts a widget into the panel.
    `void` | `insert(Widget child, java.lang.String text, boolean asHtml, int beforeIndex)` Inserts a widget into the panel.
    `void` | `insert(Widget child, java.lang.String text, int beforeIndex)` Inserts a widget into the panel.
    `void` | `insert(Widget child, Widget tab, int beforeIndex)` Inserts a widget into the panel.
    `boolean` | `isAnimationVertical()` Check whether or not transitions slide in vertically or horizontally.
    `java.util.Iterator<Widget>` | `iterator()` Gets an iterator for the contained widgets.
    `boolean` | `remove(int index)` Removes the widget at the specified index.
    `boolean` | `remove(Widget w)` Removes a child widget.
    `void` | `selectTab(int index)` Programmatically selects the specified tab and fires events.
    `void` | `selectTab(int index, boolean fireEvents)` Programmatically selects the specified tab.
    `void` | `selectTab(IsWidget child)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `selectTab(IsWidget child, boolean fireEvents)` Convenience overload to allow `IsWidget` to be used directly.
    `void` | `selectTab(Widget child)` Programmatically selects the specified tab and fires events.
    `void` | `selectTab(Widget child, boolean fireEvents)` Programmatically selects the specified tab.
    `void` | `setAnimationDuration(int duration)` Set the duration of the animated transition between tabs.
    `void` | `setAnimationVertical(boolean isVertical)` Set whether or not transitions slide in vertically or horizontally.
    `void` | `setTabHTML(int index, SafeHtml html)` Sets a tab's HTML contents.
    `void` | `setTabHTML(int index, java.lang.String html)` Sets a tab's HTML contents.
    `void` | `setTabText(int index, java.lang.String text)` Sets a tab's text contents.

    - ### Methods inherited from class com.google.gwt.user.client.ui.ResizeComposite

      `initWidget, onResize`

    - ### Methods inherited from class com.google.gwt.user.client.ui.Composite

      `claimElement, getWidget, initializeClaimedElement, isAttached, onAttach, onBrowserEvent, onDetach, render, render, resolvePotentialElement, setWidget`

    - ### Methods inherited from class com.google.gwt.user.client.ui.Widget

      `addAttachHandler, addBitlessDomHandler, addDomHandler, addHandler, asWidget, asWidgetOrNull, createHandlerManager, delegateEvent, doAttachChildren, doDetachChildren, ensureHandlers, fireEvent, getHandlerCount, getHandlerManager, getLayoutData, getParent, isOrWasAttached, onLoad, onUnload, removeFromParent, replaceElement, setLayoutData, setParent, sinkEvents`

    - ### Methods inherited from class com.google.gwt.user.client.ui.UIObject

      `addStyleDependentName, addStyleName, ensureDebugId, ensureDebugId, ensureDebugId, getAbsoluteLeft, getAbsoluteTop, getElement, getOffsetHeight, getOffsetWidth, getStyleElement, getStyleName, getStyleName, getStylePrimaryName, getStylePrimaryName, getTitle, isVisible, isVisible, onEnsureDebugId, removeStyleDependentName, removeStyleName, setElement, setElement, setHeight, setPixelSize, setSize, setStyleDependentName, setStyleName, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setTitle, setVisible, setVisible, setWidth, sinkBitlessEvent, toString, unsinkEvents`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

    - ### Methods inherited from interface com.google.gwt.event.shared.HasHandlers

      `fireEvent`

- - ### Constructor Detail

    - #### TabLayoutPanel

          public TabLayoutPanel(double barHeight,
                        Style.Unit barUnit)

      Creates an empty tab panel.
      Parameters:
        `barHeight` - the size of the tab bar
        `barUnit` - the unit in which the tab bar size is specified

  - ### Method Detail

    - #### add

          public void add(IsWidget w)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### add

          public void add(IsWidget w,
                 IsWidget tab)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### add

          public void add(IsWidget w,
                 java.lang.String text)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### add

          public void add(IsWidget w,
                 java.lang.String text,
                 boolean asHtml)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### add

          public void add(Widget w)

      Description copied from interface: `HasWidgets`
      Adds a child widget.
      Specified by:
        `add` in interface `HasWidgets`
      Parameters:
        `w` - the widget to be added

    - #### add

          public void add(Widget child,
                 java.lang.String text)

      Adds a widget to the panel. If the Widget is already attached, it will be moved to the right-most index.
      Parameters:
        `child` - the widget to be added
        `text` - the text to be shown on its tab

    - #### add

          public void add(Widget child,
                 SafeHtml html)

      Adds a widget to the panel. If the Widget is already attached, it will be moved to the right-most index.
      Parameters:
        `child` - the widget to be added
        `html` - the html to be shown on its tab

    - #### add

          public void add(Widget child,
                 java.lang.String text,
                 boolean asHtml)

      Adds a widget to the panel. If the Widget is already attached, it will be moved to the right-most index.
      Parameters:
        `child` - the widget to be added
        `text` - the text to be shown on its tab
        `asHtml` - `true` to treat the specified text as HTML

    - #### add

          public void add(Widget child,
                 Widget tab)

      Adds a widget to the panel. If the Widget is already attached, it will be moved to the right-most index.
      Parameters:
        `child` - the widget to be added
        `tab` - the widget to be placed in the associated tab

    - #### addBeforeSelectionHandler

          public HandlerRegistration addBeforeSelectionHandler(BeforeSelectionHandler<java.lang.Integer> handler)

      Description copied from interface: `HasBeforeSelectionHandlers`
      Adds a `BeforeSelectionEvent` handler.
      Specified by:
        `addBeforeSelectionHandler` in interface `HasBeforeSelectionHandlers<java.lang.Integer>`
      Parameters:
        `handler` - the handler
      Returns:
        the registration for the event

    - #### addSelectionHandler

          public HandlerRegistration addSelectionHandler(SelectionHandler<java.lang.Integer> handler)

      Description copied from interface: `HasSelectionHandlers`
      Adds a `SelectionEvent` handler.
      Specified by:
        `addSelectionHandler` in interface `HasSelectionHandlers<java.lang.Integer>`
      Parameters:
        `handler` - the handler
      Returns:
        the registration for the event

    - #### animate

          public void animate(int duration)

      Description copied from interface: `AnimatedLayout`
      Layout children, animating over the specified period of time.
      Specified by:
        `animate` in interface `AnimatedLayout`
      Parameters:
        `duration` - the animation duration, in milliseconds

    - #### animate

          public void animate(int duration,
                     Layout.AnimationCallback callback)

      Description copied from interface: `AnimatedLayout`
      Layout children, animating over the specified period of time.

      This method provides a callback that will be informed of animation updates. This can be used to create more complex animation effects.

      Specified by:
        `animate` in interface `AnimatedLayout`
      Parameters:
        `duration` - the animation duration, in milliseconds
        `callback` - the animation callback

    - #### clear

          public void clear()

      Description copied from interface: `HasWidgets`
      Removes all child widgets.
      Specified by:
        `clear` in interface `HasWidgets`

    - #### forceLayout

          public void forceLayout()

      Description copied from interface: `AnimatedLayout`
      Layout children immediately.

      This is not normally necessary, unless you want to update child widgets' positions explicitly to create a starting point for a subsequent call to `AnimatedLayout.animate(int)`.

      Specified by:
        `forceLayout` in interface `AnimatedLayout`
      See Also:
        `AnimatedLayout.animate(int)`, `AnimatedLayout.animate(int, Layout.AnimationCallback)`

    - #### getAnimationDuration

          public int getAnimationDuration()

      Get the duration of the animated transition between tabs.
      Returns:
        the duration in milliseconds

    - #### getSelectedIndex

          public int getSelectedIndex()

      Gets the index of the currently-selected tab.
      Returns:
        the selected index, or `-1` if none is selected.

    - #### getTabWidget

          public Widget getTabWidget(int index)

      Gets the widget in the tab at the given index.
      Parameters:
        `index` - the index of the tab to be retrieved
      Returns:
        the tab's widget

    - #### getTabWidget

          public Widget getTabWidget(IsWidget child)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### getTabWidget

          public Widget getTabWidget(Widget child)

      Gets the widget in the tab associated with the given child widget.
      Parameters:
        `child` - the child whose tab is to be retrieved
      Returns:
        the tab's widget

    - #### getWidget

          public Widget getWidget(int index)

      Returns the widget at the given index.
      Specified by:
        `getWidget` in interface `IndexedPanel`
      Parameters:
        `index` - the child widget's index
      Returns:
        the child widget

    - #### getWidgetCount

          public int getWidgetCount()

      Returns the number of tabs and widgets.
      Specified by:
        `getWidgetCount` in interface `IndexedPanel`
      Returns:
        the number of children

    - #### getWidgetIndex

          public int getWidgetIndex(IsWidget child)

      Convenience overload to allow `IsWidget` to be used directly.
      Specified by:
        `getWidgetIndex` in interface `IndexedPanel.ForIsWidget`

    - #### getWidgetIndex

          public int getWidgetIndex(Widget child)

      Returns the index of the given child, or -1 if it is not a child.
      Specified by:
        `getWidgetIndex` in interface `IndexedPanel`
      Parameters:
        `child` - the widget to be found
      Returns:
        the widget's index, or `-1` if it is not a child of this panel

    - #### insert

          public void insert(IsWidget child,
                    int beforeIndex)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### insert

          public void insert(IsWidget child,
                    IsWidget tab,
                    int beforeIndex)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### insert

          public void insert(IsWidget child,
                    java.lang.String text,
                    boolean asHtml,
                    int beforeIndex)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### insert

          public void insert(IsWidget child,
                    java.lang.String text,
                    int beforeIndex)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### insert

          public void insert(Widget child,
                    int beforeIndex)

      Inserts a widget into the panel. If the Widget is already attached, it will be moved to the requested index.
      Parameters:
        `child` - the widget to be added
        `beforeIndex` - the index before which it will be inserted

    - #### insert

          public void insert(Widget child,
                    SafeHtml html,
                    int beforeIndex)

      Inserts a widget into the panel. If the Widget is already attached, it will be moved to the requested index.
      Parameters:
        `child` - the widget to be added
        `html` - the html to be shown on its tab
        `beforeIndex` - the index before which it will be inserted

    - #### insert

          public void insert(Widget child,
                    java.lang.String text,
                    boolean asHtml,
                    int beforeIndex)

      Inserts a widget into the panel. If the Widget is already attached, it will be moved to the requested index.
      Parameters:
        `child` - the widget to be added
        `text` - the text to be shown on its tab
        `asHtml` - `true` to treat the specified text as HTML
        `beforeIndex` - the index before which it will be inserted

    - #### insert

          public void insert(Widget child,
                    java.lang.String text,
                    int beforeIndex)

      Inserts a widget into the panel. If the Widget is already attached, it will be moved to the requested index.
      Parameters:
        `child` - the widget to be added
        `text` - the text to be shown on its tab
        `beforeIndex` - the index before which it will be inserted

    - #### insert

          public void insert(Widget child,
                    Widget tab,
                    int beforeIndex)

      Inserts a widget into the panel. If the Widget is already attached, it will be moved to the requested index.
      Parameters:
        `child` - the widget to be added
        `tab` - the widget to be placed in the associated tab
        `beforeIndex` - the index before which it will be inserted

    - #### isAnimationVertical

          public boolean isAnimationVertical()

      Check whether or not transitions slide in vertically or horizontally. Defaults to horizontally.
      Returns:
        true for vertical transitions, false for horizontal

    - #### iterator

          public java.util.Iterator<Widget> iterator()

      Description copied from interface: `HasWidgets`
      Gets an iterator for the contained widgets. This iterator is required to implement `Iterator.remove()`.
      Specified by:
        `iterator` in interface `HasWidgets`
      Specified by:
        `iterator` in interface `java.lang.Iterable<Widget>`

    - #### remove

          public boolean remove(int index)

      Description copied from interface: `IndexedPanel`
      Removes the widget at the specified index.
      Specified by:
        `remove` in interface `IndexedPanel`
      Parameters:
        `index` - the index of the widget to be removed
      Returns:
        `false` if the widget is not present

    - #### remove

          public boolean remove(Widget w)

      Description copied from interface: `HasWidgets`
      Removes a child widget.
      Specified by:
        `remove` in interface `HasWidgets`
      Parameters:
        `w` - the widget to be removed
      Returns:
        `true` if the widget was present

    - #### selectTab

          public void selectTab(int index)

      Programmatically selects the specified tab and fires events.
      Parameters:
        `index` - the index of the tab to be selected

    - #### selectTab

          public void selectTab(int index,
                       boolean fireEvents)

      Programmatically selects the specified tab.
      Parameters:
        `index` - the index of the tab to be selected
        `fireEvents` - true to fire events, false not to

    - #### selectTab

          public void selectTab(IsWidget child)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### selectTab

          public void selectTab(IsWidget child,
                       boolean fireEvents)

      Convenience overload to allow `IsWidget` to be used directly.

    - #### selectTab

          public void selectTab(Widget child)

      Programmatically selects the specified tab and fires events.
      Parameters:
        `child` - the child whose tab is to be selected

    - #### selectTab

          public void selectTab(Widget child,
                       boolean fireEvents)

      Programmatically selects the specified tab.
      Parameters:
        `child` - the child whose tab is to be selected
        `fireEvents` - true to fire events, false not to

    - #### setAnimationDuration

          public void setAnimationDuration(int duration)

      Set the duration of the animated transition between tabs.
      Parameters:
        `duration` - the duration in milliseconds.

    - #### setAnimationVertical

          public void setAnimationVertical(boolean isVertical)

      Set whether or not transitions slide in vertically or horizontally.
      Parameters:
        `isVertical` - true for vertical transitions, false for horizontal

    - #### setTabHTML

          public void setTabHTML(int index,
                        java.lang.String html)

      Sets a tab's HTML contents. Use care when setting an object's HTML; it is an easy way to expose script-based security problems. Consider using `setTabHTML(int, SafeHtml)` or `setTabText(int, String)` whenever possible.
      Parameters:
        `index` - the index of the tab whose HTML is to be set
        `html` - the tab's new HTML contents

    - #### setTabHTML

          public void setTabHTML(int index,
                        SafeHtml html)

      Sets a tab's HTML contents.
      Parameters:
        `index` - the index of the tab whose HTML is to be set
        `html` - the tab's new HTML contents

    - #### setTabText

          public void setTabText(int index,
                        java.lang.String text)

      Sets a tab's text contents.
      Parameters:
        `index` - the index of the tab whose text is to be set
        `text` - the object's new text