gecko-dev/widget/cocoa/ViewRegion.mm
Markus Stange 5ee44d898b Bug 1070710 - Add mozilla::ViewRegion which assembles a LayoutDeviceIntRegion as NSViews. r=spohl
MozReview-Commit-ID: RrVzLcv27T

--HG--
extra : amend_source : d14dc262bf300a81feaf03954d5783ea1c7451cb
extra : histedit_source : aa39b53c122a719a5181b5a41d5351bbdf04cbd8
2016-07-16 17:07:45 -04:00

72 lines
2.2 KiB
Plaintext

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "ViewRegion.h"
#import <Cocoa/Cocoa.h>
using namespace mozilla;
ViewRegion::~ViewRegion()
{
for (size_t i = 0; i < mViews.Length(); i++) {
[mViews[i] removeFromSuperview];
}
}
bool
ViewRegion::UpdateRegion(const LayoutDeviceIntRegion& aRegion,
const nsChildView& aCoordinateConverter,
NSView* aContainerView,
NSView* (^aViewCreationCallback)())
{
if (mRegion == aRegion) {
return false;
}
// We need to construct the required region using as many EffectViews
// as necessary. We try to update the geometry of existing views if
// possible, or create new ones or remove old ones if the number of
// rects in the region has changed.
nsTArray<NSView*> viewsToRecycle;
mViews.SwapElements(viewsToRecycle);
// The mViews array is now empty.
size_t i = 0;
for (auto iter = aRegion.RectIter();
!iter.Done() || i < viewsToRecycle.Length();
i++) {
if (!iter.Done()) {
NSView* view = nil;
NSRect rect = aCoordinateConverter.DevPixelsToCocoaPoints(iter.Get());
if (i < viewsToRecycle.Length()) {
view = viewsToRecycle[i];
} else {
view = aViewCreationCallback();
[aContainerView addSubview:view];
// Now that the view is in the view hierarchy, it'll be kept alive by
// its superview, so we can drop our reference.
[view release];
}
if (!NSEqualRects(rect, [view frame])) {
[view setFrame:rect];
}
[view setNeedsDisplay:YES];
mViews.AppendElement(view);
iter.Next();
} else {
// Our new region is made of fewer rects than the old region, so we can
// remove this view. We only have a weak reference to it, so removing it
// from the view hierarchy will release it.
[viewsToRecycle[i] removeFromSuperview];
}
}
mRegion = aRegion;
return true;
}