void
nsHTMLButtonControlFrame::ReflowButtonContents(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aButtonDesiredSize,
const nsHTMLReflowState& aButtonReflowState,
nsIFrame* aFirstKid)
{
// Buttons have some bonus renderer-determined border/padding,
// which occupies part of the button's content-box area:
const nsMargin focusPadding = mRenderer.GetAddedButtonBorderAndPadding();
WritingMode wm = aFirstKid->GetWritingMode();
LogicalSize availSize = aButtonReflowState.ComputedSize(GetWritingMode());
availSize.BSize(wm) = NS_INTRINSICSIZE;
// Indent the child inside us by the focus border. We must do this separate
// from the regular border.
availSize.ISize(wm) -= LogicalMargin(wm, focusPadding).IStartEnd(wm);
// See whether out availSize's width is big enough. If it's smaller than our
// intrinsic min width, that means that the kid wouldn't really fit; for a
// better look in such cases we adjust the available width and our left
// offset to allow the kid to spill left into our padding.
nscoord xoffset = focusPadding.left +
aButtonReflowState.ComputedPhysicalBorderPadding().left;
nscoord extrawidth = GetMinISize(aButtonReflowState.rendContext) -
aButtonReflowState.ComputedWidth();
if (extrawidth > 0) {
nscoord extraleft = extrawidth / 2;
nscoord extraright = extrawidth - extraleft;
NS_ASSERTION(extraright >=0, "How'd that happen?");
// Do not allow the extras to be bigger than the relevant padding
extraleft = std::min(extraleft, aButtonReflowState.ComputedPhysicalPadding().left);
extraright = std::min(extraright, aButtonReflowState.ComputedPhysicalPadding().right);
xoffset -= extraleft;
availSize.SetWidth(wm, availSize.Width(wm) + extraleft + extraright);
}
availSize.SetWidth(wm, std::max(availSize.Width(wm), 0));
// Give child a clone of the button's reflow state, with height/width reduced
// by focusPadding, so that descendants with height:100% don't protrude.
nsHTMLReflowState adjustedButtonReflowState =
CloneReflowStateWithReducedContentBox(aButtonReflowState, focusPadding);
nsHTMLReflowState contentsReflowState(aPresContext,
adjustedButtonReflowState,
aFirstKid, availSize);
nsReflowStatus contentsReflowStatus;
nsHTMLReflowMetrics contentsDesiredSize(aButtonReflowState);
ReflowChild(aFirstKid, aPresContext,
contentsDesiredSize, contentsReflowState,
xoffset,
focusPadding.top + aButtonReflowState.ComputedPhysicalBorderPadding().top,
0, contentsReflowStatus);
MOZ_ASSERT(NS_FRAME_IS_COMPLETE(contentsReflowStatus),
"We gave button-contents frame unconstrained available height, "
"so it should be complete");
// Compute the button's content-box height:
nscoord buttonContentBoxHeight = 0;
if (aButtonReflowState.ComputedHeight() != NS_INTRINSICSIZE) {
// Button has a fixed height -- that's its content-box height.
buttonContentBoxHeight = aButtonReflowState.ComputedHeight();
} else {
// Button is intrinsically sized -- it should shrinkwrap the
// button-contents' height, plus any focus-padding space:
buttonContentBoxHeight =
contentsDesiredSize.Height() + focusPadding.TopBottom();
// Make sure we obey min/max-height in the case when we're doing intrinsic
// sizing (we get it for free when we have a non-intrinsic
// aButtonReflowState.ComputedHeight()). Note that we do this before
// adjusting for borderpadding, since mComputedMaxHeight and
// mComputedMinHeight are content heights.
buttonContentBoxHeight =
NS_CSS_MINMAX(buttonContentBoxHeight,
aButtonReflowState.ComputedMinHeight(),
aButtonReflowState.ComputedMaxHeight());
}
// Center child vertically in the button
// (technically, inside of the button's focus-padding area)
nscoord extraSpace =
buttonContentBoxHeight - focusPadding.TopBottom() -
contentsDesiredSize.Height();
nscoord yoffset = std::max(0, extraSpace / 2);
// Adjust yoffset to be in terms of the button's frame-rect, instead of
// its focus-padding rect:
yoffset += focusPadding.top + aButtonReflowState.ComputedPhysicalBorderPadding().top;
// Place the child
FinishReflowChild(aFirstKid, aPresContext,
contentsDesiredSize, &contentsReflowState,
xoffset, yoffset, 0);
// Make sure we have a useful 'ascent' value for the child
if (contentsDesiredSize.BlockStartAscent() ==
nsHTMLReflowMetrics::ASK_FOR_BASELINE) {
WritingMode wm = aButtonReflowState.GetWritingMode();
contentsDesiredSize.SetBlockStartAscent(aFirstKid->GetLogicalBaseline(wm));
}
// OK, we're done with the child frame.
// Use what we learned to populate the button frame's reflow metrics.
// * Button's height & width are content-box size + border-box contribution:
aButtonDesiredSize.Width() = aButtonReflowState.ComputedWidth() +
aButtonReflowState.ComputedPhysicalBorderPadding().LeftRight();
aButtonDesiredSize.Height() = buttonContentBoxHeight +
aButtonReflowState.ComputedPhysicalBorderPadding().TopBottom();
// * Button's ascent is its child's ascent, plus the child's y-offset
// within our frame:
aButtonDesiredSize.SetBlockStartAscent(contentsDesiredSize.BlockStartAscent() +
yoffset);
aButtonDesiredSize.SetOverflowAreasToDesiredBounds();
}
