gecko-dev/layout/xul/nsListBoxLayout.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsListBoxLayout.h"
#include "nsListBoxBodyFrame.h"
#include "nsBox.h"
#include "nsBoxLayoutState.h"
#include "nsIScrollableFrame.h"
#include "nsIReflowCallback.h"
#include "mozilla/dom/NameSpaceConstants.h"
#include "nsGkAtoms.h"
#include "nsContentUtils.h"
nsListBoxLayout::nsListBoxLayout() : nsGridRowGroupLayout()
{
}
////////// nsBoxLayout //////////////
nsSize
nsListBoxLayout::GetPrefSize(nsIFrame* aBox, nsBoxLayoutState& aBoxLayoutState)
{
nsSize pref = nsGridRowGroupLayout::GetPrefSize(aBox, aBoxLayoutState);
nsListBoxBodyFrame* frame = static_cast<nsListBoxBodyFrame*>(aBox);
if (frame) {
nscoord rowheight = frame->GetRowHeightAppUnits();
pref.height = frame->GetRowCount() * rowheight;
// Pad the height.
nscoord y = frame->GetAvailableHeight();
if (pref.height > y && y > 0 && rowheight > 0) {
nscoord m = (pref.height-y)%rowheight;
nscoord remainder = m == 0 ? 0 : rowheight - m;
pref.height += remainder;
}
if (nsContentUtils::HasNonEmptyAttr(frame->GetContent(), kNameSpaceID_None,
nsGkAtoms::sizemode)) {
nscoord width = frame->ComputeIntrinsicISize(aBoxLayoutState);
if (width > pref.width)
pref.width = width;
}
}
return pref;
}
nsSize
nsListBoxLayout::GetMinSize(nsIFrame* aBox, nsBoxLayoutState& aBoxLayoutState)
{
nsSize minSize = nsGridRowGroupLayout::GetMinSize(aBox, aBoxLayoutState);
nsListBoxBodyFrame* frame = static_cast<nsListBoxBodyFrame*>(aBox);
if (frame) {
nscoord rowheight = frame->GetRowHeightAppUnits();
minSize.height = frame->GetRowCount() * rowheight;
// Pad the height.
nscoord y = frame->GetAvailableHeight();
if (minSize.height > y && y > 0 && rowheight > 0) {
nscoord m = (minSize.height-y)%rowheight;
nscoord remainder = m == 0 ? 0 : rowheight - m;
minSize.height += remainder;
}
if (nsContentUtils::HasNonEmptyAttr(frame->GetContent(), kNameSpaceID_None,
nsGkAtoms::sizemode)) {
nscoord width = frame->ComputeIntrinsicISize(aBoxLayoutState);
if (width > minSize.width)
minSize.width = width;
}
}
return minSize;
}
nsSize
nsListBoxLayout::GetMaxSize(nsIFrame* aBox, nsBoxLayoutState& aBoxLayoutState)
{
nsSize maxSize = nsGridRowGroupLayout::GetMaxSize(aBox, aBoxLayoutState);
nsListBoxBodyFrame* frame = static_cast<nsListBoxBodyFrame*>(aBox);
if (frame) {
nscoord rowheight = frame->GetRowHeightAppUnits();
maxSize.height = frame->GetRowCount() * rowheight;
// Pad the height.
nscoord y = frame->GetAvailableHeight();
if (maxSize.height > y && y > 0 && rowheight > 0) {
nscoord m = (maxSize.height-y)%rowheight;
nscoord remainder = m == 0 ? 0 : rowheight - m;
maxSize.height += remainder;
}
}
return maxSize;
}
NS_IMETHODIMP
nsListBoxLayout::Layout(nsIFrame* aBox, nsBoxLayoutState& aState)
{
return LayoutInternal(aBox, aState);
}
/////////// nsListBoxLayout /////////////////////////
/**
* Called to layout our our children. Does no frame construction
*/
NS_IMETHODIMP
nsListBoxLayout::LayoutInternal(nsIFrame* aBox, nsBoxLayoutState& aState)
{
int32_t redrawStart = -1;
// Get the start y position.
nsListBoxBodyFrame* body = static_cast<nsListBoxBodyFrame*>(aBox);
if (!body) {
NS_ERROR("Frame encountered that isn't a listboxbody!");
return NS_ERROR_FAILURE;
}
nsMargin margin;
// Get our client rect.
nsRect clientRect;
aBox->GetClientRect(clientRect);
// Get the starting y position and the remaining available
// height.
nscoord availableHeight = body->GetAvailableHeight();
nscoord yOffset = body->GetYPosition();
if (availableHeight <= 0) {
bool fixed = (body->GetFixedRowSize() != -1);
if (fixed)
availableHeight = 10;
else
return NS_OK;
}
// run through all our currently created children
nsIFrame* box = nsBox::GetChildBox(body);
// if the reason is resize or initial we must relayout.
nscoord rowHeight = body->GetRowHeightAppUnits();
while (box) {
// If this box is dirty or if it has dirty children, we
// call layout on it.
nsRect childRect(box->GetRect());
box->GetMargin(margin);
// relayout if we must or we are dirty or some of our children are dirty
// or the client area is wider than us
// XXXldb There should probably be a resize check here too!
if (NS_SUBTREE_DIRTY(box) || childRect.width < clientRect.width) {
childRect.x = 0;
childRect.y = yOffset;
childRect.width = clientRect.width;
nsSize size = box->GetPrefSize(aState);
body->SetRowHeight(size.height);
childRect.height = rowHeight;
childRect.Deflate(margin);
box->SetBounds(aState, childRect);
box->Layout(aState);
} else {
// if the child did not need to be relayed out. Then its easy.
// Place the child by just grabbing its rect and adjusting the y.
int32_t newPos = yOffset+margin.top;
// are we pushing down or pulling up any rows?
// Then we may have to redraw everything below the moved
// rows.
if (redrawStart == -1 && childRect.y != newPos)
redrawStart = newPos;
childRect.y = newPos;
box->SetBounds(aState, childRect);
}
// Ok now the available size gets smaller and we move the
// starting position of the next child down some.
nscoord size = childRect.height + margin.top + margin.bottom;
yOffset += size;
availableHeight -= size;
box = nsBox::GetNextBox(box);
}
// We have enough available height left to add some more rows
// Since we can't do this during layout, we post a callback
// that will be processed after the reflow completes.
body->PostReflowCallback();
// if rows were pushed down or pulled up because some rows were added
// before them then redraw everything under the inserted rows. The inserted
// rows will automatically be redrawn because the were marked dirty on insertion.
if (redrawStart > -1) {
aBox->Redraw(aState);
}
return NS_OK;
}
// Creation Routines ///////////////////////////////////////////////////////////////////////
already_AddRefed<nsBoxLayout> NS_NewListBoxLayout()
{
nsRefPtr<nsBoxLayout> layout = new nsListBoxLayout();
return layout.forget();
}