com.google.gwt.user.client.ui

## Class HorizontalPanel

- 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.CellPanel
          - - com.google.gwt.user.client.ui.HorizontalPanel

- All Implemented Interfaces:
    HasAttachHandlers, HasHandlers, EventListener, HasAlignment, HasHorizontalAlignment, HasVerticalAlignment, HasVisibility, HasWidgets, HasWidgets.ForIsWidget, IndexedPanel, IndexedPanel.ForIsWidget, InsertPanel, InsertPanel.ForIsWidget, IsWidget, java.lang.Iterable<Widget>

      public class HorizontalPanel
      extends CellPanel
      implements HasAlignment, InsertPanel.ForIsWidget

  A panel that lays all of its widgets out in a single horizontal column.

- - ### 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.HasHorizontalAlignment

      `HasHorizontalAlignment.AutoHorizontalAlignmentConstant, HasHorizontalAlignment.HorizontalAlignmentConstant`

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

      `HasVerticalAlignment.VerticalAlignmentConstant`

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

      `InsertPanel.ForIsWidget`

    - ### 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`

    - ### Fields inherited from interface com.google.gwt.user.client.ui.HasHorizontalAlignment

      `ALIGN_CENTER, ALIGN_DEFAULT, ALIGN_JUSTIFY, ALIGN_LEFT, ALIGN_LOCALE_END, ALIGN_LOCALE_START, ALIGN_RIGHT`

    - ### Fields inherited from interface com.google.gwt.user.client.ui.HasVerticalAlignment

      `ALIGN_BOTTOM, ALIGN_MIDDLE, ALIGN_TOP`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `HorizontalPanel()` Creates an empty horizontal panel.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `add(Widget w)` Adds a child widget.
    `HasHorizontalAlignment.HorizontalAlignmentConstant` | `getHorizontalAlignment()` Gets the horizontal alignment.
    `HasVerticalAlignment.VerticalAlignmentConstant` | `getVerticalAlignment()` Gets the vertical alignment.
    `void` | `insert(IsWidget w, int beforeIndex)`
    `void` | `insert(Widget w, int beforeIndex)` Inserts a child widget before the specified index.
    `protected void` | `onEnsureDebugId(java.lang.String baseID)` Affected Elements: -# = the cell at the given index.
    `boolean` | `remove(Widget w)` Removes a child widget.
    `void` | `setHorizontalAlignment(HasHorizontalAlignment.HorizontalAlignmentConstant align)` Sets the default horizontal alignment to be used for widgets added to this panel.
    `void` | `setVerticalAlignment(HasVerticalAlignment.VerticalAlignmentConstant align)` Sets the default vertical alignment to be used for widgets added to this panel.

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

      `getBody, getSpacing, getTable, getWidgetTd, setBorderWidth, setCellHeight, setCellHeight, setCellHorizontalAlignment, setCellHorizontalAlignment, setCellHorizontalAlignment, setCellHorizontalAlignment, setCellVerticalAlignment, setCellVerticalAlignment, setCellVerticalAlignment, setCellVerticalAlignment, setCellWidth, setCellWidth, setSpacing`

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

      `add, add, adjustIndex, checkIndexBoundsForAccess, checkIndexBoundsForInsertion, doLogicalClear, getChildren, getWidget, getWidgetCount, getWidgetIndex, getWidgetIndex, insert, insert, iterator, remove`

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

      `add, adopt, clear, doAttachChildren, doDetachChildren, orphan, remove`

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

      `addAttachHandler, addBitlessDomHandler, addDomHandler, addHandler, asWidget, asWidgetOrNull, createHandlerManager, delegateEvent, ensureHandlers, fireEvent, getHandlerCount, getHandlerManager, getLayoutData, getParent, isAttached, isOrWasAttached, onAttach, onBrowserEvent, onDetach, onLoad, onUnload, removeFromParent, replaceElement, setLayoutData, setParent, sinkEvents, unsinkEvents`

    - ### 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, removeStyleDependentName, removeStyleName, resolvePotentialElement, setElement, setElement, setHeight, setPixelSize, setSize, setStyleDependentName, setStyleName, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setTitle, setVisible, setVisible, setWidth, sinkBitlessEvent, toString`

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

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

    - ### Methods inherited from interface com.google.gwt.user.client.ui.InsertPanel.ForIsWidget

      `add`

    - ### Methods inherited from interface com.google.gwt.user.client.ui.IndexedPanel.ForIsWidget

      `getWidgetIndex`

    - ### Methods inherited from interface com.google.gwt.user.client.ui.IndexedPanel

      `getWidget, getWidgetCount, getWidgetIndex, remove`

    - ### Methods inherited from interface java.lang.Iterable

      `forEach, spliterator`

- - ### Constructor Detail

    - #### HorizontalPanel

          public HorizontalPanel()

      Creates an empty horizontal panel.

  - ### Method Detail

    - #### 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:
        `HasWidgets.add(Widget)`

    - #### getHorizontalAlignment

          public HasHorizontalAlignment.HorizontalAlignmentConstant getHorizontalAlignment()

      Description copied from interface: `HasHorizontalAlignment`
      Gets the horizontal alignment.
      Specified by:
        `getHorizontalAlignment` in interface `HasHorizontalAlignment`
      Returns:
        the current horizontal alignment ( `HasHorizontalAlignment.ALIGN_LEFT`, `HasHorizontalAlignment.ALIGN_CENTER`, `HasHorizontalAlignment.ALIGN_RIGHT`, `HasHorizontalAlignment.ALIGN_JUSTIFY`, or null).

    - #### getVerticalAlignment

          public HasVerticalAlignment.VerticalAlignmentConstant getVerticalAlignment()

      Description copied from interface: `HasVerticalAlignment`
      Gets the vertical alignment.
      Specified by:
        `getVerticalAlignment` in interface `HasVerticalAlignment`
      Returns:
        the current vertical alignment.

    - #### 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

    - #### remove

          public boolean remove(Widget w)

      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:
        `w` - the widget to be removed
      Returns:
        `true` if the child was present

    - #### setHorizontalAlignment

          public void setHorizontalAlignment(HasHorizontalAlignment.HorizontalAlignmentConstant align)

      Sets the default horizontal alignment to be used for widgets added to this panel. It only applies to widgets added after this property is set.
      Specified by:
        `setHorizontalAlignment` in interface `HasHorizontalAlignment`
      Parameters:
        `align` - the horizontal alignment ( `HasHorizontalAlignment.ALIGN_LEFT`, `HasHorizontalAlignment.ALIGN_CENTER`, `HasHorizontalAlignment.ALIGN_RIGHT`, `HasHorizontalAlignment.ALIGN_JUSTIFY`, `HasHorizontalAlignment.ALIGN_LOCALE_START`, or `HasHorizontalAlignment.ALIGN_LOCALE_END`).
      See Also:
        `HasHorizontalAlignment.setHorizontalAlignment(HasHorizontalAlignment.HorizontalAlignmentConstant)`

    - #### setVerticalAlignment

          public void setVerticalAlignment(HasVerticalAlignment.VerticalAlignmentConstant align)

      Sets the default vertical alignment to be used for widgets added to this panel. It only applies to widgets added after this property is set.
      Specified by:
        `setVerticalAlignment` in interface `HasVerticalAlignment`
      Parameters:
        `align` - the vertical alignment ( `HasVerticalAlignment.ALIGN_TOP`, `HasVerticalAlignment.ALIGN_MIDDLE`, or `HasVerticalAlignment.ALIGN_BOTTOM`).
      See Also:
        `HasVerticalAlignment.setVerticalAlignment(HasVerticalAlignment.VerticalAlignmentConstant)`

    - #### onEnsureDebugId

          protected void onEnsureDebugId(java.lang.String baseID)

      Affected Elements:
      - -# = the cell at the given index.
      Overrides:
        `onEnsureDebugId` in class `UIObject`
      Parameters:
        `baseID` - the base ID used by the main element
      See Also:
        `UIObject.onEnsureDebugId(String)`