DragDropInteractionState.mm [plain text]
/*
* Copyright (C) 2017 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#import "config.h"
#import "DragDropInteractionState.h"
#if PLATFORM(IOS_FAMILY) && ENABLE(DRAG_SUPPORT)
#import "Logging.h"
#import <WebCore/DragItem.h>
#import <WebCore/Image.h>
#import <wtf/cocoa/VectorCocoa.h>
namespace WebKit {
using namespace WebCore;
static UIDragItem *dragItemMatchingIdentifier(id <UIDragSession> session, NSInteger identifier)
{
for (UIDragItem *item in session.items) {
id context = item.privateLocalContext;
if ([context isKindOfClass:[NSNumber class]] && [context integerValue] == identifier)
return item;
}
return nil;
}
static RetainPtr<UITargetedDragPreview> createTargetedDragPreview(UIImage *image, UIView *rootView, UIView *previewContainer, const FloatRect& frameInRootViewCoordinates, const Vector<FloatRect>& clippingRectsInFrameCoordinates, UIColor *backgroundColor, UIBezierPath *visiblePath)
{
if (frameInRootViewCoordinates.isEmpty() || !image || !previewContainer.window)
return nullptr;
FloatRect frameInContainerCoordinates = [rootView convertRect:frameInRootViewCoordinates toView:previewContainer];
if (frameInContainerCoordinates.isEmpty())
return nullptr;
FloatSize scalingRatio = frameInContainerCoordinates.size() / frameInRootViewCoordinates.size();
auto clippingRectValuesInFrameCoordinates = createNSArray(clippingRectsInFrameCoordinates, [&] (auto rect) {
rect.scale(scalingRatio);
return [NSValue valueWithCGRect:rect];
});
auto imageView = adoptNS([[UIImageView alloc] initWithImage:image]);
[imageView setFrame:frameInContainerCoordinates];
RetainPtr<UIDragPreviewParameters> parameters;
if ([clippingRectValuesInFrameCoordinates count])
parameters = adoptNS([[UIDragPreviewParameters alloc] initWithTextLineRects:clippingRectValuesInFrameCoordinates.get()]);
else
parameters = adoptNS([[UIDragPreviewParameters alloc] init]);
if (backgroundColor)
[parameters setBackgroundColor:backgroundColor];
if (visiblePath)
[parameters setVisiblePath:visiblePath];
CGPoint centerInContainerCoordinates = { CGRectGetMidX(frameInContainerCoordinates), CGRectGetMidY(frameInContainerCoordinates) };
auto target = adoptNS([[UIDragPreviewTarget alloc] initWithContainer:previewContainer center:centerInContainerCoordinates]);
return adoptNS([[UITargetedDragPreview alloc] initWithView:imageView.get() parameters:parameters.get() target:target.get()]);
}
static RetainPtr<UIImage> uiImageForImage(Image* image)
{
if (!image)
return nullptr;
auto nativeImage = image->nativeImage();
if (!nativeImage)
return nullptr;
return adoptNS([[UIImage alloc] initWithCGImage:nativeImage->platformImage().get()]);
}
static bool shouldUseDragImageToCreatePreviewForDragSource(const DragSourceState& source)
{
if (!source.image)
return false;
#if ENABLE(INPUT_TYPE_COLOR)
if (source.action.contains(DragSourceAction::Color))
return true;
#endif
return source.action.containsAny({ DragSourceAction::DHTML, DragSourceAction::Image });
}
static bool shouldUseVisiblePathToCreatePreviewForDragSource(const DragSourceState& source)
{
if (!source.visiblePath)
return false;
#if ENABLE(INPUT_TYPE_COLOR)
if (source.action.contains(DragSourceAction::Color))
return true;
#endif
return false;
}
static bool shouldUseTextIndicatorToCreatePreviewForDragSource(const DragSourceState& source)
{
if (!source.indicatorData)
return false;
if (source.action.containsAny({ DragSourceAction::Link, DragSourceAction::Selection }))
return true;
#if ENABLE(ATTACHMENT_ELEMENT)
if (source.action.contains(DragSourceAction::Attachment))
return true;
#endif
return false;
}
static bool canUpdatePreviewForActiveDragSource(const DragSourceState& source)
{
if (!source.possiblyNeedsDragPreviewUpdate)
return false;
#if ENABLE(INPUT_TYPE_COLOR)
if (source.action.contains(DragSourceAction::Color))
return true;
#endif
if (source.action.contains(DragSourceAction::Link) && !source.action.contains(DragSourceAction::Image))
return true;
return false;
}
Optional<DragSourceState> DragDropInteractionState::activeDragSourceForItem(UIDragItem *item) const
{
if (![item.privateLocalContext isKindOfClass:[NSNumber class]])
return WTF::nullopt;
auto identifier = [(NSNumber *)item.privateLocalContext integerValue];
for (auto& source : m_activeDragSources) {
if (source.itemIdentifier == identifier)
return source;
}
return WTF::nullopt;
}
bool DragDropInteractionState::anyActiveDragSourceIs(WebCore::DragSourceAction action) const
{
for (auto& source : m_activeDragSources) {
if (source.action.contains(action))
return true;
}
return false;
}
void DragDropInteractionState::prepareForDragSession(id <UIDragSession> session, dispatch_block_t completionHandler)
{
m_dragSession = session;
m_dragStartCompletionBlock = completionHandler;
}
void DragDropInteractionState::dragSessionWillBegin()
{
m_didBeginDragging = true;
updatePreviewsForActiveDragSources();
}
void DragDropInteractionState::setDefaultDropPreview(UIDragItem *item, UITargetedDragPreview *preview)
{
m_defaultDropPreviews.append({ item, preview });
}
UITargetedDragPreview *DragDropInteractionState::defaultDropPreview(UIDragItem *item) const
{
auto matchIndex = m_defaultDropPreviews.findMatching([&] (auto& itemAndPreview) {
return itemAndPreview.item == item;
});
return matchIndex == notFound ? nil : m_defaultDropPreviews[matchIndex].preview.get();
}
BlockPtr<void(UITargetedDragPreview *)> DragDropInteractionState::dropPreviewProvider(UIDragItem *item)
{
auto matchIndex = m_delayedItemPreviewProviders.findMatching([&] (auto& itemAndProvider) {
return itemAndProvider.item == item;
});
if (matchIndex == notFound)
return nil;
return m_delayedItemPreviewProviders[matchIndex].provider;
}
void DragDropInteractionState::prepareForDelayedDropPreview(UIDragItem *item, void(^provider)(UITargetedDragPreview *preview))
{
m_delayedItemPreviewProviders.append({ item, provider });
}
void DragDropInteractionState::deliverDelayedDropPreview(UIView *contentView, UIView *previewContainer, const WebCore::TextIndicatorData& indicator)
{
if (m_delayedItemPreviewProviders.isEmpty())
return;
auto textIndicatorImage = uiImageForImage(indicator.contentImage.get());
auto preview = createTargetedDragPreview(textIndicatorImage.get(), contentView, previewContainer, indicator.textBoundingRectInRootViewCoordinates, indicator.textRectsInBoundingRectCoordinates, [UIColor colorWithCGColor:cachedCGColor(indicator.estimatedBackgroundColor)], nil);
for (auto& itemAndPreviewProvider : m_delayedItemPreviewProviders)
itemAndPreviewProvider.provider(preview.get());
m_delayedItemPreviewProviders.clear();
}
void DragDropInteractionState::deliverDelayedDropPreview(UIView *contentView, CGRect unobscuredContentRect, NSArray<UIDragItem *> *items, const Vector<IntRect>& placeholderRects)
{
if (items.count != placeholderRects.size()) {
RELEASE_LOG(DragAndDrop, "Failed to animate image placeholders: number of drag items (%tu) does not match number of placeholders (%tu)", items.count, placeholderRects.size());
clearAllDelayedItemPreviewProviders();
return;
}
for (size_t i = 0; i < placeholderRects.size(); ++i) {
UIDragItem *item = [items objectAtIndex:i];
auto& placeholderRect = placeholderRects[i];
auto provider = dropPreviewProvider(item);
if (!provider)
continue;
auto defaultPreview = defaultDropPreview(item);
auto defaultPreviewSize = [defaultPreview size];
if (!defaultPreview || defaultPreviewSize.width <= 0 || defaultPreviewSize.height <= 0 || placeholderRect.isEmpty()) {
provider(nil);
continue;
}
FloatRect previewIntersectionRect = enclosingIntRect(CGRectIntersection(unobscuredContentRect, placeholderRect));
if (previewIntersectionRect.isEmpty()) {
// If the preview rect is completely offscreen, don't bother trying to clip out or scale the default preview;
// simply retarget the default preview.
auto target = adoptNS([[UIDragPreviewTarget alloc] initWithContainer:contentView center:placeholderRect.center()]);
provider([defaultPreview retargetedPreviewWithTarget:target.get()]);
continue;
}
// Targeted previews don't clip to the bounds of any enclosing view; this means that when targeting previews outside
// the visible bounds of the content view, the preview will spill out the web view. This is most noticeable when
// dropping a tall image into Mail compose on iOS 13, where the bottom of the compose window is not flush against
// the bottom of the window. To mitigate this, we use the preview target's `visiblePath` property to clip the default
// drop preview's view, by the same proportion that the final placeholder image is clipped (with respect to the
// unobscured content rect).
auto previewBounds = [defaultPreview view].bounds;
auto insetPreviewBounds = UIEdgeInsetsInsetRect(previewBounds, {
(previewIntersectionRect.y() - placeholderRect.y()) / placeholderRect.height() * previewBounds.size.height,
(previewIntersectionRect.x() - placeholderRect.x()) / placeholderRect.width() * previewBounds.size.width,
(placeholderRect.maxY() - previewIntersectionRect.maxY()) / placeholderRect.height() * previewBounds.size.height,
(placeholderRect.maxX() - previewIntersectionRect.maxX()) / placeholderRect.width() * previewBounds.size.width
});
auto transform = CGAffineTransformMakeScale(placeholderRect.width() / defaultPreviewSize.width, placeholderRect.height() / defaultPreviewSize.height);
auto target = adoptNS([[UIDragPreviewTarget alloc] initWithContainer:contentView center:previewIntersectionRect.center() transform:transform]);
[defaultPreview parameters].visiblePath = [UIBezierPath bezierPathWithRect:insetPreviewBounds];
auto newPreview = adoptNS([[UITargetedDragPreview alloc] initWithView:[defaultPreview view] parameters:[defaultPreview parameters] target:target.get()]);
provider(newPreview.get());
}
m_delayedItemPreviewProviders.clear();
}
void DragDropInteractionState::clearAllDelayedItemPreviewProviders()
{
for (auto& itemAndPreviewProvider : m_delayedItemPreviewProviders)
itemAndPreviewProvider.provider(nil);
m_delayedItemPreviewProviders.clear();
}
UITargetedDragPreview *DragDropInteractionState::previewForDragItem(UIDragItem *item, UIView *contentView, UIView *previewContainer) const
{
auto foundSource = activeDragSourceForItem(item);
if (!foundSource)
return nil;
auto& source = foundSource.value();
if (shouldUseDragImageToCreatePreviewForDragSource(source)) {
if (shouldUseVisiblePathToCreatePreviewForDragSource(source)) {
auto path = source.visiblePath.value();
UIBezierPath *visiblePath = [UIBezierPath bezierPathWithCGPath:path.ensurePlatformPath()];
return createTargetedDragPreview(source.image.get(), contentView, previewContainer, source.dragPreviewFrameInRootViewCoordinates, { }, nil, visiblePath).autorelease();
}
return createTargetedDragPreview(source.image.get(), contentView, previewContainer, source.dragPreviewFrameInRootViewCoordinates, { }, nil, nil).autorelease();
}
if (shouldUseTextIndicatorToCreatePreviewForDragSource(source)) {
auto indicator = source.indicatorData.value();
auto textIndicatorImage = uiImageForImage(indicator.contentImage.get());
return createTargetedDragPreview(textIndicatorImage.get(), contentView, previewContainer, indicator.textBoundingRectInRootViewCoordinates, indicator.textRectsInBoundingRectCoordinates, [UIColor colorWithCGColor:cachedCGColor(indicator.estimatedBackgroundColor)], nil).autorelease();
}
return nil;
}
void DragDropInteractionState::dragSessionWillDelaySetDownAnimation(dispatch_block_t completion)
{
m_dragCancelSetDownBlock = completion;
}
bool DragDropInteractionState::shouldRequestAdditionalItemForDragSession(id <UIDragSession> session) const
{
return m_dragSession == session && !m_addDragItemCompletionBlock && !m_dragStartCompletionBlock;
}
void DragDropInteractionState::dragSessionWillRequestAdditionalItem(void (^completion)(NSArray <UIDragItem *> *))
{
clearStagedDragSource();
m_addDragItemCompletionBlock = completion;
}
void DragDropInteractionState::dropSessionDidEnterOrUpdate(id <UIDropSession> session, const DragData& dragData)
{
m_dropSession = session;
m_lastGlobalPosition = dragData.globalPosition();
}
void DragDropInteractionState::stageDragItem(const DragItem& item, UIImage *dragImage)
{
static NSInteger currentDragSourceItemIdentifier = 0;
m_adjustedPositionForDragEnd = item.eventPositionInContentCoordinates;
m_stagedDragSource = {{
item.sourceAction,
item.eventPositionInContentCoordinates,
item.dragPreviewFrameInRootViewCoordinates,
dragImage,
item.image.indicatorData(),
item.image.visiblePath(),
item.title.isEmpty() ? nil : (NSString *)item.title,
item.url.isEmpty() ? nil : (NSURL *)item.url,
true, // We assume here that drag previews need to be updated until proven otherwise in updatePreviewsForActiveDragSources().
++currentDragSourceItemIdentifier
}};
}
bool DragDropInteractionState::hasStagedDragSource() const
{
return m_stagedDragSource && !stagedDragSource().action.isEmpty();
}
void DragDropInteractionState::clearStagedDragSource(DidBecomeActive didBecomeActive)
{
if (didBecomeActive == DidBecomeActive::Yes)
m_activeDragSources.append(stagedDragSource());
m_stagedDragSource = WTF::nullopt;
}
void DragDropInteractionState::dragAndDropSessionsDidEnd()
{
clearAllDelayedItemPreviewProviders();
// If any of UIKit's completion blocks are still in-flight when the drag interaction ends, we need to ensure that they are still invoked
// to prevent UIKit from getting into an inconsistent state.
if (auto completionBlock = takeDragCancelSetDownBlock())
completionBlock();
if (auto completionBlock = takeAddDragItemCompletionBlock())
completionBlock(@[ ]);
if (auto completionBlock = takeDragStartCompletionBlock())
completionBlock();
}
void DragDropInteractionState::updatePreviewsForActiveDragSources()
{
for (auto& source : m_activeDragSources) {
if (!canUpdatePreviewForActiveDragSource(source))
continue;
UIDragItem *dragItem = dragItemMatchingIdentifier(m_dragSession.get(), source.itemIdentifier);
if (!dragItem)
continue;
if (source.action.contains(DragSourceAction::Link)) {
dragItem.previewProvider = [title = retainPtr((NSString *)source.linkTitle), url = retainPtr((NSURL *)source.linkURL), center = source.adjustedOrigin] () -> UIDragPreview * {
UIURLDragPreviewView *previewView = [UIURLDragPreviewView viewWithTitle:title.get() URL:url.get()];
previewView.center = center;
UIDragPreviewParameters *parameters = [[[UIDragPreviewParameters alloc] initWithTextLineRects:@[ [NSValue valueWithCGRect:previewView.bounds] ]] autorelease];
return [[[UIDragPreview alloc] initWithView:previewView parameters:parameters] autorelease];
};
}
#if ENABLE(INPUT_TYPE_COLOR)
else if (source.action.contains(DragSourceAction::Color)) {
dragItem.previewProvider = [image = source.image] () -> UIDragPreview * {
UIImageView *imageView = [[[UIImageView alloc] initWithImage:image.get()] autorelease];
UIDragPreviewParameters *parameters = [[[UIDragPreviewParameters alloc] initWithTextLineRects:@[ [NSValue valueWithCGRect:[imageView bounds]] ]] autorelease];
return [[[UIDragPreview alloc] initWithView:imageView parameters:parameters] autorelease];
};
}
#endif
source.possiblyNeedsDragPreviewUpdate = false;
}
}
} // namespace WebKit
#endif // PLATFORM(IOS_FAMILY) && ENABLE(DRAG_SUPPORT)