protected void OnMouseDown(MouseDownEvent e)
{
if (CanStartManipulation(e))
{
VisualSplitter visualSplitter = target as VisualSplitter;
FlexDirection flexDirection = visualSplitter.resolvedStyle.flexDirection;
if (m_AffectedElements != null)
{
VisualElementListPool.Release(m_AffectedElements);
}
m_AffectedElements = visualSplitter.GetAffectedVisualElements();
var shouldUseEvent = false;
for (int i = 0; i < m_AffectedElements.Count - 1; ++i)
{
VisualElement visualElement = m_AffectedElements[i];
Rect splitterRect = visualSplitter.GetSplitterRect(visualElement);
if (splitterRect.Contains(e.localMousePosition))
{
bool isReverse = flexDirection == FlexDirection.RowReverse || flexDirection == FlexDirection.ColumnReverse;
if (isReverse)
{
m_ActiveVisualElementIndex = i + 1;
m_NextVisualElementIndex = i;
}
else
{
m_ActiveVisualElementIndex = i;
m_NextVisualElementIndex = i + 1;
}
shouldUseEvent = true;
}
}
if (shouldUseEvent)
{
m_Active = true;
target.CaptureMouse();
e.StopPropagation();
e.PreventDefault();
}
}
}
protected void OnMouseMove(MouseMoveEvent e)
{
if (m_Active)
{
// These calculations should only work if flex-basis is auto.
// However, Yoga implementation of flex-basis 0 is broken and behaves much like
// flex-basis auto, so it currently works with flex-basis 0 too.
VisualSplitter visualSplitter = target as VisualSplitter;
VisualElement visualElement = m_AffectedElements[m_ActiveVisualElementIndex];
VisualElement nextVisualElement = m_AffectedElements[m_NextVisualElementIndex];
FlexDirection flexDirection = visualSplitter.resolvedStyle.flexDirection;
bool isVertical = flexDirection == FlexDirection.Column || flexDirection == FlexDirection.ColumnReverse;
float relativeMousePosition;
if (isVertical)
{
float minHeight = visualElement.resolvedStyle.minHeight == StyleKeyword.Auto ? 0 : visualElement.resolvedStyle.minHeight.value;
float nextMinHeight = nextVisualElement.resolvedStyle.minHeight == StyleKeyword.Auto ? 0 : nextVisualElement.resolvedStyle.minHeight.value;
float availableHeight = visualElement.layout.height + nextVisualElement.layout.height - minHeight - nextMinHeight;
float maxHeight = visualElement.resolvedStyle.maxHeight.value <= 0 ? availableHeight : visualElement.resolvedStyle.maxHeight.value;
relativeMousePosition = (Math.Min(e.localMousePosition.y, visualElement.layout.yMin + maxHeight) - visualElement.layout.yMin - minHeight) / availableHeight;
}
else
{
float minWidth = visualElement.resolvedStyle.minWidth == StyleKeyword.Auto ? 0 : visualElement.resolvedStyle.minWidth.value;
float nextMinWidth = nextVisualElement.resolvedStyle.minWidth == StyleKeyword.Auto ? 0 : nextVisualElement.resolvedStyle.minWidth.value;
float availableWidth = visualElement.layout.width + nextVisualElement.layout.width - minWidth - nextMinWidth;
float maxWidth = visualElement.resolvedStyle.maxWidth.value <= 0 ? availableWidth : visualElement.resolvedStyle.maxWidth.value;
relativeMousePosition = (Math.Min(e.localMousePosition.x, visualElement.layout.xMin + maxWidth) - visualElement.layout.xMin - minWidth) / availableWidth;
}
relativeMousePosition = Math.Max(0.0f, Math.Min(0.999f, relativeMousePosition));
float totalFlex = visualElement.resolvedStyle.flexGrow + nextVisualElement.resolvedStyle.flexGrow;
visualElement.style.flexGrow = relativeMousePosition * totalFlex;
nextVisualElement.style.flexGrow = (1.0f - relativeMousePosition) * totalFlex;
e.StopPropagation();
}
}
