private void animationTimer_Tick(object sender, System.EventArgs e)
{
// ---------------------------------------------------------------
// Gradually reduce the interval between timer events so that the
// animation begins slowly and eventually accelerates to completion
// ---------------------------------------------------------------
if (animationTimer.Interval > 10) {
animationTimer.Interval -= 10 ;
} else {
animationHeightAdjustment += 2 ;
}
// Increase transparency as we collapse
if ((animationOpacity + 5) < byte.MaxValue) {
animationOpacity += 5 ;
}
int currOpacity = animationOpacity ;
switch (PanelDrawState) {
case XPPanelDrawState.Expanding:
// still room to expand?
if ((Height + animationHeightAdjustment) < ExpandedHeight) {
Height += animationHeightAdjustment;
// notify panel state change listeners so they can react
OnPanelStateChange() ;
} else {
// we are done so we dont want any transparency
currOpacity = byte.MaxValue ;
PanelState = XPPanelState.Expanded ;
PanelDrawState = XPPanelDrawState.Normal ;
}
break;
case XPPanelDrawState.Collapsing:
// still something to collapse
if ((Height - animationHeightAdjustment) > xpPanelRect.Top) {
Height -= animationHeightAdjustment ;
// continue decreasing opacity
currOpacity = byte.MaxValue - animationOpacity ;
// notify panel state change listeners so they can react
OnPanelStateChange() ;
} else {
// we are done so we dont want any transparency
currOpacity = byte.MaxValue ;
PanelState = XPPanelState.Collapsed ;
PanelDrawState = XPPanelDrawState.Normal ;
}
break;
default:
return ;
}
// set the opacity for all the controls on the XPPanel
SetControlsOpacity(currOpacity);
// make panel colors more/less transparent
panelGradient.Start = SetColorAlpha(currOpacity,panelGradient.Start);
panelGradient.End = SetColorAlpha(currOpacity,panelGradient.End);
PanelBrush = null ;
panelOutlineColor = SetColorAlpha(currOpacity,panelOutlineColor );
// hide/show controls based on the height of the XPPanel (as it shrinks/grows)
SetControlsVisible();
// are we done?
if (!IsActive) {
animationTimer.Enabled = false;
}
Invalidate();
}
/// <summary>
/// Routine to toggle the state of <c>XPPanel</c> from Expanded to Collapsed
/// (or visa-versa)
/// </summary>
/// <remarks>
/// This routine provides a way to trigger the visual animation of
/// expanding/collapsing a <c>XPPanel</c>
/// </remarks>
public virtual void TogglePanelState()
{
// If we are animating, start it now...
if (animationRate != 0) {
if (IsExpanded) {
PanelDrawState = XPPanelDrawState.Collapsing ;
} else {
PanelDrawState = XPPanelDrawState.Expanding ;
}
StartAnimation() ;
} else {
// No animation. Just expand/collapse immediately
// (note: set the DrawState to internal so that expandedHeight does not
// get mucked up)
if (IsExpanded) {
PanelDrawState = XPPanelDrawState.Internal ;
PanelState = XPPanelState.Collapsed ;
} else {
PanelDrawState = XPPanelDrawState.Internal ;
PanelState = XPPanelState.Expanded ;
}
// we are back to normal
PanelDrawState = XPPanelDrawState.Normal ;
}
}
