Package com.badlogic.gdx.scenes.scene2d.ui

Class ScrollPane

  • All Implemented Interfaces:
    Cullable, Layout
    Direct Known Subclasses:
    SelectBox.SelectBoxScrollPane
    public class ScrollPane
extends WidgetGroup
    A group that scrolls a child actor using scrollbars and/or mouse or touch dragging.

    The actor is sized to its preferred size. If the actor's preferred width or height is less than the size of this scroll pane, it is set to the size of this scroll pane. Scrollbars appear when the actor is larger than the scroll pane.

    The scroll pane's preferred size is that of the child actor. At this size, the child actor will not need to scroll, so the scroll pane is typically sized by ignoring the preferred size in one or both directions.

    • Constructor Detail

      • ScrollPane

        public ScrollPane​(@Null
                  Actor actor)
        Parameters:
        actor - May be null.

      • ScrollPane

        public ScrollPane​(@Null
                  Actor actor,
                  Skin skin)
        Parameters:
        actor - May be null.

      • ScrollPane

        public ScrollPane​(@Null
                  Actor actor,
                  Skin skin,
                  java.lang.String styleName)
        Parameters:
        actor - May be null.

    • Method Detail

      • addCaptureListener

        protected void addCaptureListener()

      • getFlickScrollListener

        protected ActorGestureListener getFlickScrollListener()
        Called by constructor.

      • addScrollListener

        protected void addScrollListener()

      • setScrollbarsVisible

        public void setScrollbarsVisible​(boolean visible)
        Shows or hides the scrollbars for when using setFadeScrollBars(boolean).

      • cancelTouchFocus

        public void cancelTouchFocus()
        Cancels the stage's touch focus for all listeners except this scroll pane's flick scroll listener. This causes any actors inside the scrollpane that have received touchDown to receive touchUp.
        See Also:
        setCancelTouchFocus(boolean)

      • cancel

        public void cancel()
        If currently scrolling by tracking a touch down, stop scrolling.

      • act

        public void act​(float delta)
        Description copied from class: Actor
        Updates the actor based on time. Typically this is called each frame by Stage.act(float).

        The default implementation calls Action.act(float) on each action and removes actions that are complete.

        Overrides:
        act in class Group
        Parameters:
        delta - Time in seconds since the last frame.

      • layout

        public void layout()
        Description copied from interface: Layout
        Computes and caches any information needed for drawing and, if this actor has children, positions and sizes each child, calls Layout.invalidate() on any each child whose width or height has changed, and calls Layout.validate() on each child. This method should almost never be called directly, instead Layout.validate() should be used.
        Specified by:
        layout in interface Layout
        Overrides:
        layout in class WidgetGroup

      • draw

        public void draw​(Batch batch,
                 float parentAlpha)
        Description copied from class: WidgetGroup
        If this method is overridden, the super method or WidgetGroup.validate() should be called to ensure the widget group is laid out.
        Overrides:
        draw in class WidgetGroup
        parentAlpha - The parent alpha, to be multiplied with this actor's alpha, allowing the parent's alpha to affect all children.

      • drawScrollBars

        protected void drawScrollBars​(Batch batch,
                              float r,
                              float g,
                              float b,
                              float a)
        Renders the scrollbars after the children have been drawn. If the scrollbars faded out, a is zero and rendering can be skipped.

      • fling

        public void fling​(float flingTime,
                  float velocityX,
                  float velocityY)
        Generate fling gesture.
        Parameters:
        flingTime - Time in seconds for which you want to fling last.
        velocityX - Velocity for horizontal direction.
        velocityY - Velocity for vertical direction.

      • setActor

        public void setActor​(@Null
                     Actor actor)
        Sets the Actor embedded in this scroll pane.
        Parameters:
        actor - May be null to remove any current actor.

      • getActor

        @Null
public Actor getActor()
        Returns the actor embedded in this scroll pane, or null.

      • addActor

        @Deprecated
public void addActor​(Actor actor)
        Deprecated.
        ScrollPane may have only a single child.
        Description copied from class: Group
        Adds an actor as a child of this group, removing it from its previous parent. If the actor is already a child of this group, no changes are made.
        Overrides:
        addActor in class Group
        See Also:
        setActor(Actor)

      • addActorAt

        @Deprecated
public void addActorAt​(int index,
                       Actor actor)
        Deprecated.
        ScrollPane may have only a single child.
        Description copied from class: Group
        Adds an actor as a child of this group at a specific index, removing it from its previous parent. If the actor is already a child of this group, no changes are made.
        Overrides:
        addActorAt in class Group
        Parameters:
        index - May be greater than the number of children.
        See Also:
        setActor(Actor)

      • addActorBefore

        @Deprecated
public void addActorBefore​(Actor actorBefore,
                           Actor actor)
        Deprecated.
        ScrollPane may have only a single child.
        Description copied from class: Group
        Adds an actor as a child of this group immediately before another child actor, removing it from its previous parent. If the actor is already a child of this group, no changes are made.
        Overrides:
        addActorBefore in class Group
        See Also:
        setActor(Actor)

      • addActorAfter

        @Deprecated
public void addActorAfter​(Actor actorAfter,
                          Actor actor)
        Deprecated.
        ScrollPane may have only a single child.
        Description copied from class: Group
        Adds an actor as a child of this group immediately after another child actor, removing it from its previous parent. If the actor is already a child of this group, no changes are made. If actorAfter is not in this group, the actor is added as the last child.
        Overrides:
        addActorAfter in class Group
        See Also:
        setActor(Actor)

      • removeActorAt

        public Actor removeActorAt​(int index,
                           boolean unfocus)
        Description copied from class: Group
        Removes an actor from this group. If the actor will not be used again and has actions, they should be cleared so the actions will be returned to their pool, if any. This is not done automatically.
        Overrides:
        removeActorAt in class Group
        unfocus - If true, Stage.unfocus(Actor) is called.
        Returns:
        the actor removed from this group.

      • scrollX

        protected void scrollX​(float pixelsX)
        Called whenever the x scroll amount is changed.

      • scrollY

        protected void scrollY​(float pixelsY)
        Called whenever the y scroll amount is changed.

      • visualScrollX

        protected void visualScrollX​(float pixelsX)
        Called whenever the visual x scroll amount is changed.

      • visualScrollY

        protected void visualScrollY​(float pixelsY)
        Called whenever the visual y scroll amount is changed.

      • getMouseWheelX

        protected float getMouseWheelX()
        Returns the amount to scroll horizontally when the mouse wheel is scrolled.

      • getMouseWheelY

        protected float getMouseWheelY()
        Returns the amount to scroll vertically when the mouse wheel is scrolled.

      • setScrollX

        public void setScrollX​(float pixels)

      • getScrollX

        public float getScrollX()
        Returns the x scroll position in pixels, where 0 is the left of the scroll pane.

      • setScrollY

        public void setScrollY​(float pixels)

      • getScrollY

        public float getScrollY()
        Returns the y scroll position in pixels, where 0 is the top of the scroll pane.

      • updateVisualScroll

        public void updateVisualScroll()
        Sets the visual scroll amount equal to the scroll amount. This can be used when setting the scroll amount without animating.

      • getVisualScrollX

        public float getVisualScrollX()

      • getVisualScrollY

        public float getVisualScrollY()

      • getVisualScrollPercentX

        public float getVisualScrollPercentX()

      • getVisualScrollPercentY

        public float getVisualScrollPercentY()

      • getScrollPercentX

        public float getScrollPercentX()

      • setScrollPercentX

        public void setScrollPercentX​(float percentX)

      • getScrollPercentY

        public float getScrollPercentY()

      • setScrollPercentY

        public void setScrollPercentY​(float percentY)

      • setFlickScroll

        public void setFlickScroll​(boolean flickScroll)

      • setFlickScrollTapSquareSize

        public void setFlickScrollTapSquareSize​(float halfTapSquareSize)

      • scrollTo

        public void scrollTo​(float x,
                     float y,
                     float width,
                     float height)
        Sets the scroll offset so the specified rectangle is fully in view, if possible. Coordinates are in the scroll pane actor's coordinate system.

      • scrollTo

        public void scrollTo​(float x,
                     float y,
                     float width,
                     float height,
                     boolean centerHorizontal,
                     boolean centerVertical)
        Sets the scroll offset so the specified rectangle is fully in view, and optionally centered vertically and/or horizontally, if possible. Coordinates are in the scroll pane actor's coordinate system.

      • getMaxX

        public float getMaxX()
        Returns the maximum scroll value in the x direction.

      • getMaxY

        public float getMaxY()
        Returns the maximum scroll value in the y direction.

      • getScrollBarHeight

        public float getScrollBarHeight()

      • getScrollBarWidth

        public float getScrollBarWidth()

      • getScrollWidth

        public float getScrollWidth()
        Returns the width of the scrolled viewport.

      • getScrollHeight

        public float getScrollHeight()
        Returns the height of the scrolled viewport.

      • isScrollX

        public boolean isScrollX()
        Returns true if the actor is larger than the scroll pane horizontally.

      • isScrollY

        public boolean isScrollY()
        Returns true if the actor is larger than the scroll pane vertically.

      • setScrollingDisabled

        public void setScrollingDisabled​(boolean x,
                                 boolean y)
        Disables scrolling in a direction. The actor will be sized to the FlickScrollPane in the disabled direction.

      • isScrollingDisabledX

        public boolean isScrollingDisabledX()

      • isScrollingDisabledY

        public boolean isScrollingDisabledY()

      • isLeftEdge

        public boolean isLeftEdge()

      • isRightEdge

        public boolean isRightEdge()

      • isTopEdge

        public boolean isTopEdge()

      • isBottomEdge

        public boolean isBottomEdge()

      • isDragging

        public boolean isDragging()

      • isPanning

        public boolean isPanning()

      • isFlinging

        public boolean isFlinging()

      • setVelocityX

        public void setVelocityX​(float velocityX)

      • getVelocityX

        public float getVelocityX()
        Gets the flick scroll x velocity.

      • setVelocityY

        public void setVelocityY​(float velocityY)

      • getVelocityY

        public float getVelocityY()
        Gets the flick scroll y velocity.

      • setOverscroll

        public void setOverscroll​(boolean overscrollX,
                          boolean overscrollY)
        For flick scroll, if true the actor can be scrolled slightly past its bounds and will animate back to its bounds when scrolling is stopped. Default is true.

      • setupOverscroll

        public void setupOverscroll​(float distance,
                            float speedMin,
                            float speedMax)
        For flick scroll, sets the overscroll distance in pixels and the speed it returns to the actor's bounds in seconds. Default is 50, 30, 200.

      • getOverscrollDistance

        public float getOverscrollDistance()

      • setForceScroll

        public void setForceScroll​(boolean x,
                           boolean y)
        Forces enabling scrollbars (for non-flick scroll) and overscrolling (for flick scroll) in a direction, even if the contents do not exceed the bounds in that direction.

      • isForceScrollX

        public boolean isForceScrollX()

      • isForceScrollY

        public boolean isForceScrollY()

      • setFlingTime

        public void setFlingTime​(float flingTime)
        For flick scroll, sets the amount of time in seconds that a fling will continue to scroll. Default is 1.

      • setClamp

        public void setClamp​(boolean clamp)
        For flick scroll, prevents scrolling out of the actor's bounds. Default is true.

      • setScrollBarPositions

        public void setScrollBarPositions​(boolean bottom,
                                  boolean right)
        Set the position of the vertical and horizontal scroll bars.

      • setFadeScrollBars

        public void setFadeScrollBars​(boolean fadeScrollBars)
        When true the scrollbars don't reduce the scrollable size and fade out after some time of not being used.

      • setupFadeScrollBars

        public void setupFadeScrollBars​(float fadeAlphaSeconds,
                                float fadeDelaySeconds)

      • getFadeScrollBars

        public boolean getFadeScrollBars()

      • setScrollBarTouch

        public void setScrollBarTouch​(boolean scrollBarTouch)
        When false, the scroll bars don't respond to touch or mouse events. Default is true.

      • setSmoothScrolling

        public void setSmoothScrolling​(boolean smoothScrolling)

      • setScrollbarsOnTop

        public void setScrollbarsOnTop​(boolean scrollbarsOnTop)
        When false (the default), the actor is clipped so it is not drawn under the scrollbars. When true, the actor is clipped to the entire scroll pane bounds and the scrollbars are drawn on top of the actor. If setFadeScrollBars(boolean) is true, the scroll bars are always drawn on top.

      • getVariableSizeKnobs

        public boolean getVariableSizeKnobs()

      • setCancelTouchFocus

        public void setCancelTouchFocus​(boolean cancelTouchFocus)
        When true (default) and flick scrolling begins, cancelTouchFocus() is called. This causes any actors inside the scrollpane that have received touchDown to receive touchUp when flick scrolling begins.