com.smartgwt.client.widgets

## Class Hover

- java.lang.Object
- - com.smartgwt.client.widgets.Hover

-     public class Hover
      extends java.lang.Object

  The Hover class handles showing a simple Smart GWT canvas containing arbitrary HTML, or triggering some other action in response to a user holding the mouse-pointer (or hovering) over a specific widget.

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `Hover()`

  - ### Method Summary

    All Methods Static Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `static void` | `hide()` Hide hoverCanvas shown via `show()`
    `static void` | `show(Canvas contents, Label properties)` Displays a standard Hover canvas containing the specified canvas as the content. This method may also be called to modify the content of the hover if it is already showing.
    `static void` | `show(java.lang.String contents, Label properties)` Displays a standard Hover canvas containing the specified HTML content. This method may also be called to modify the content of the hover if it is already showing.
    `static void` | `showHoverComponent(Canvas component)` Similar to `Hover.show()` but uses the hover mechanism to display some `component` instead of showing `HTML text` in the builtin `hoverCanvas`.

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

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

- - ### Constructor Detail

    - #### Hover

          public Hover()

  - ### Method Detail

    - #### hide

          public static void hide()

      Hide hoverCanvas shown via `show()`

    - #### showHoverComponent

          public static void showHoverComponent(Canvas component)

      Similar to `Hover.show()` but uses the hover mechanism to display some `component` instead of showing `HTML text` in the builtin `hoverCanvas`. Hover.showHoverComponent() is called automatically instead of Hover.show() when `Canvas.showHoverComponents` is true.

      As with `Hover.show()`, the component-position is based on the mouse pointer position, adjusted by `leftOffset` and `topOffset`. If this position would render the component partially clipped or off-screen, it is moved to ensure the component is entirely visible.

      See `show()` for more information.

      Parameters:
        `component` - component to show using the hover mechanism

    - #### show

          public static void show(java.lang.String contents,
                                  Label properties)

      Displays a standard Hover canvas containing the specified HTML content.
      This method may also be called to modify the content of the hover if it is already showing. Call `Hover.hide` to hide the canvas again.
      A common use case for calling this method is to asynchronously fetch detail data from the server about some component, and display it in the Hover canvas when the data is returned. Note that in this case you will typically need to verify that the user is still hovering over the component in question before calling Hover.show() - if the user has moved the mouse off the component, the information will not apply to whatever is now under the mouse. Suggested approaches for handling this are to either use a `Canvas.mouseOut` handler to track when the user moves off the component, or checking `EventHandler.getTarget` as part of the asynchronous callback

      The default Hover canvas position will be based on the mouse pointer position, adjusted by `leftOffset` and `topOffset`. If this position would render the Hover canvas partially clipped, it will be automatically modified to ensure the Hover is entirely visible.

      Parameters:
        `contents` - contents for the hover. See `HTMLString`
        `properties` - object containing attributes for managing the hover canvas' appearance. Valid properties include:
        - left, top, width, height
        - baseStyle
        - opacity
        - wrap
        - moveWithMouse

    - #### show

          public static void show(Canvas contents,
                                  Label properties)

      Displays a standard Hover canvas containing the specified canvas as the content.
      This method may also be called to modify the content of the hover if it is already showing. Call `Hover.hide` to hide the canvas again.
      A common use case for calling this method is to asynchronously fetch detail data from the server about some component, and display it in the Hover canvas when the data is returned. Note that in this case you will typically need to verify that the user is still hovering over the component in question before calling Hover.show() - if the user has moved the mouse off the component, the information will not apply to whatever is now under the mouse. Suggested approaches for handling this are to either use a `Canvas.mouseOut` handler to track when the user moves off the component, or checking `EventHandler.getTarget` as part of the asynchronous callback

      The default Hover canvas position will be based on the mouse pointer position, adjusted by `leftOffset` and `topOffset`. If this position would render the Hover canvas partially clipped, it will be automatically modified to ensure the Hover is entirely visible.

      Parameters:
        `contents` - contents for the hover. See `HTMLString`
        `properties` - object containing attributes for managing the hover canvas' appearance. Valid properties include:
        - left, top, width, height
        - baseStyle
        - opacity
        - wrap
        - moveWithMouse