Example usage for com.badlogic.gdx.scenes.scene2d.utils Layout invalidate

Introduction

In this page you can find the example usage for com.badlogic.gdx.scenes.scene2d.utils Layout invalidate.

Prototype

public void invalidate();

Source Link

Document

Invalidates this actor's layout, causing #layout() to happen the next time #validate() is called.

Usage

From source file:com.anstrat.gui.SnapScrollPane.java

License:Apache License

public void layout() {
    final Drawable bg = style.background;
    final Drawable hScrollKnob = style.hScrollKnob;
    final Drawable vScrollKnob = style.vScrollKnob;

    float bgLeftWidth = 0, bgRightWidth = 0, bgTopHeight = 0, bgBottomHeight = 0;
    if (bg != null) {
        bgLeftWidth = bg.getLeftWidth();
        bgRightWidth = bg.getRightWidth();
        bgTopHeight = bg.getTopHeight();
        bgBottomHeight = bg.getBottomHeight();
    }//  w  w  w.  ja  v a2s .c o  m

    float width = getWidth();
    float height = getHeight();

    float scrollbarHeight = 0;
    if (hScrollKnob != null)
        scrollbarHeight = hScrollKnob.getMinHeight();
    if (style.hScroll != null)
        scrollbarHeight = Math.max(scrollbarHeight, style.hScroll.getMinHeight());
    float scrollbarWidth = 0;
    if (vScrollKnob != null)
        scrollbarWidth = vScrollKnob.getMinWidth();
    if (style.vScroll != null)
        scrollbarWidth = Math.max(scrollbarWidth, style.vScroll.getMinWidth());

    // Get available space size by subtracting background's padded area.
    areaWidth = width - bgLeftWidth - bgRightWidth;
    areaHeight = height - bgTopHeight - bgBottomHeight;

    if (widget == null)
        return;

    // Get widget's desired width.
    float widgetWidth, widgetHeight;
    if (widget instanceof Layout) {
        Layout layout = (Layout) widget;
        widgetWidth = layout.getPrefWidth();
        widgetHeight = layout.getPrefHeight();
    } else {
        widgetWidth = widget.getWidth();
        widgetHeight = widget.getHeight();
    }

    // Determine if horizontal/vertical scrollbars are needed.
    scrollX = forceOverscrollX || (widgetWidth > areaWidth && !disableX);
    scrollY = forceOverscrollY || (widgetHeight > areaHeight && !disableY);

    boolean fade = fadeScrollBars;
    if (!fade) {
        // Check again, now taking into account the area that's taken up by any enabled scrollbars.
        if (scrollY) {
            areaWidth -= scrollbarWidth;
            if (!scrollX && widgetWidth > areaWidth && !disableX) {
                scrollX = true;
            }
        }
        if (scrollX) {
            areaHeight -= scrollbarHeight;
            if (!scrollY && widgetHeight > areaHeight && !disableY) {
                scrollY = true;
                areaWidth -= scrollbarWidth;
            }
        }
    }

    // Set the widget area bounds.
    widgetAreaBounds.set(bgLeftWidth, bgBottomHeight, areaWidth, areaHeight);

    if (fade) {
        // Make sure widget is drawn under fading scrollbars.
        if (scrollX)
            areaHeight -= scrollbarHeight;
        if (scrollY)
            areaWidth -= scrollbarWidth;
    } else {
        if (scrollbarsOnTop) {
            // Make sure widget is drawn under non-fading scrollbars.
            if (scrollX)
                widgetAreaBounds.height += scrollbarHeight;
            if (scrollY)
                widgetAreaBounds.width += scrollbarWidth;
        } else {
            // Offset widget area y for horizontal scrollbar.
            if (scrollX)
                widgetAreaBounds.y += scrollbarHeight;
        }
    }

    // If the widget is smaller than the available space, make it take up the available space.
    widgetWidth = disableX ? width : Math.max(areaWidth, widgetWidth);
    widgetHeight = disableY ? height : Math.max(areaHeight, widgetHeight);

    maxX = widgetWidth - areaWidth;
    maxY = widgetHeight - areaHeight;
    if (fade) {
        // Make sure widget is drawn under fading scrollbars.
        if (scrollX)
            maxY -= scrollbarHeight;
        if (scrollY)
            maxX -= scrollbarWidth;
    }
    amountX = MathUtils.clamp(amountX, 0, maxX);
    amountY = MathUtils.clamp(amountY, 0, maxY);

    // Set the bounds and scroll knob sizes if scrollbars are needed.
    if (scrollX) {
        if (hScrollKnob != null) {
            float hScrollHeight = style.hScroll != null ? style.hScroll.getMinHeight()
                    : hScrollKnob.getMinHeight();
            hScrollBounds.set(bgLeftWidth, bgBottomHeight, areaWidth, hScrollHeight);
            hKnobBounds.width = Math.max(hScrollKnob.getMinWidth(),
                    (int) (hScrollBounds.width * areaWidth / widget.getWidth()));
            hKnobBounds.height = hScrollKnob.getMinHeight();
            hKnobBounds.x = hScrollBounds.x
                    + (int) ((hScrollBounds.width - hKnobBounds.width) * getScrollPercentX());
            hKnobBounds.y = hScrollBounds.y;
        } else {
            hScrollBounds.set(0, 0, 0, 0);
            hKnobBounds.set(0, 0, 0, 0);
        }
    }
    if (scrollY) {
        if (vScrollKnob != null) {
            float vScrollWidth = style.vScroll != null ? style.vScroll.getMinWidth()
                    : vScrollKnob.getMinWidth();
            vScrollBounds.set(width - bgRightWidth - vScrollWidth, height - bgTopHeight - areaHeight,
                    vScrollWidth, areaHeight);
            vKnobBounds.width = vScrollKnob.getMinWidth();
            vKnobBounds.height = Math.max(vScrollKnob.getMinHeight(),
                    (int) (vScrollBounds.height * areaHeight / widgetHeight));
            vKnobBounds.x = width - bgRightWidth - vScrollKnob.getMinWidth();
            vKnobBounds.y = vScrollBounds.y
                    + (int) ((vScrollBounds.height - vKnobBounds.height) * (1 - getScrollPercentY()));
        } else {
            vScrollBounds.set(0, 0, 0, 0);
            vKnobBounds.set(0, 0, 0, 0);
        }
    }

    if (widget.getWidth() != widgetWidth || widget.getHeight() != widgetHeight) {
        widget.setWidth(widgetWidth);
        widget.setHeight(widgetHeight);
        if (widget instanceof Layout) {
            Layout layout = (Layout) widget;
            layout.invalidate();
            layout.validate();
        }
    } else {
        if (widget instanceof Layout)
            ((Layout) widget).validate();
    }
}

---