public void PutBefore(MHRoot p, MHRoot pRef)
{
int nPos = CurrentApp().FindOnStack(p);
if (nPos == -1)
{
return; // If it's not there do nothing
}
MHVisible pVis = (MHVisible)p; // Can now safely cast it.
int nRef = CurrentApp().FindOnStack(pRef);
if (nRef == -1)
{
return; // If the reference visible isn't there do nothing.
}
CurrentApp().DisplayStack.RemoveAt(nPos);
if (nRef >= nPos)
{
nRef--; // The position of the reference may have shifted
}
CurrentApp().DisplayStack.InsertAt(pVis, nRef + 1);
// Redraw the area occupied by the moved item. We might be able to reduce
// the area to be redrawn by looking at the way it is affected by other items
// in the stack. We could also see whether it's currently active.
Redraw(pVis.GetVisibleArea()); // Request a redraw
}
protected void DrawRegion(Region toDraw, int nStackPos)
{
if (IsRegionEmpty(toDraw))
{
return;
}
while (nStackPos >= 0)
{
MHVisible pItem = CurrentApp().DisplayStack.GetAt(nStackPos);
// Work out how much of the area we want to draw is included in this visible.
// The visible area will be empty if the item is transparent or not active.
Region drawArea = pItem.GetVisibleArea().Clone();
drawArea.Intersect(toDraw);
if (!IsRegionEmpty(drawArea))
{ // It contributes something.
// Remove the opaque area of this item from the region we have left.
// If this item is (semi-)transparent this will not remove anything.
Region newDraw = toDraw.Clone();
newDraw.Exclude(pItem.GetOpaqueArea());
DrawRegion(newDraw, nStackPos - 1); // Do the items further down if any.
// Now we've drawn anything below this we can draw this item on top.
pItem.Display(this);
return;
}
nStackPos--;
}
// We've drawn all the visibles and there's still some undrawn area.
// Fill it with black.
m_Context.DrawBackground(toDraw);
}
// Display stack and draw functions.
public void AddToDisplayStack(MHVisible pVis)
{
if (CurrentApp().FindOnStack(pVis) != -1)
{
return; // Return if it's already there.
}
CurrentApp().DisplayStack.Append(pVis);
Redraw(pVis.GetVisibleArea()); // Request a redraw
}
public void RemoveFromDisplayStack(MHVisible pVis)
{
int nPos = CurrentApp().FindOnStack(pVis);
if (nPos == -1)
{
return;
}
CurrentApp().DisplayStack.RemoveAt(nPos);
Redraw(pVis.GetVisibleArea()); // Request a redraw
}
public void SendToBack(MHRoot p)
{
int nPos = CurrentApp().FindOnStack(p);
if (nPos == -1)
{
return; // If it's not there do nothing
}
MHVisible pVis = (MHVisible)p; // Can now safely cast it.
CurrentApp().DisplayStack.RemoveAt(nPos); // Remove it from its present posn
CurrentApp().DisplayStack.InsertAt(pVis, 0); // Put it on the bottom.
Redraw(pVis.GetVisibleArea()); // Request a redraw
}
// Functions to alter the Z-order.
public void BringToFront(MHRoot p)
{
int nPos = CurrentApp().FindOnStack(p);
if (nPos == -1)
{
return; // If it's not there do nothing
}
MHVisible pVis = (MHVisible)p; // Can now safely cast it.
CurrentApp().DisplayStack.RemoveAt(nPos); // Remove it from its present posn
CurrentApp().DisplayStack.Append((MHVisible)pVis); // Push it on the top.
Redraw(pVis.GetVisibleArea()); // Request a redraw
}
public void PutBehind(MHRoot p, MHRoot pRef)
{
int nPos = CurrentApp().FindOnStack(p);
if (nPos == -1)
{
return; // If it's not there do nothing
}
int nRef = CurrentApp().FindOnStack(pRef);
if (nRef == -1)
{
return; // If the reference visible isn't there do nothing.
}
MHVisible pVis = (MHVisible)p; // Can now safely cast it.
CurrentApp().DisplayStack.RemoveAt(nPos);
if (nRef >= nPos)
{
nRef--; // The position of the reference may have shifted
}
CurrentApp().DisplayStack.InsertAt((MHVisible)pVis, nRef); // Shift the reference and anything above up.
Redraw(pVis.GetVisibleArea()); // Request a redraw
}