-/* Copyright (c) 2019 Samsung Electronics Co., Ltd.
+/* Copyright (c) 2020 Samsung Electronics Co., Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
[EditorBrowsable(EditorBrowsableState.Never)]
public class ScrollableBase : Control
{
- static bool LayoutDebugScrollableBase = false; // Debug flag
+ static bool LayoutDebugScrollableBase = false; // Debug flag
private Direction mScrollingDirection = Direction.Vertical;
private bool mScrollEnabled = true;
private int mPageWidth = 0;
ScrollableBase scrollableBase = this.Owner as ScrollableBase;
if (scrollableBase)
{
- scrollingDirection = scrollableBase.ScrollingDirection;
+ scrollingDirection = scrollableBase.ScrollingDirection;
}
// measure child, should be a single scrolling child
- foreach( LayoutItem childLayout in LayoutChildren )
+ foreach (LayoutItem childLayout in LayoutChildren)
{
if (childLayout != null)
{
// Get size of child
// Use an Unspecified MeasureSpecification mode so scrolling child is not restricted to it's parents size in Height (for vertical scrolling)
// or Width for horizontal scrolling
- MeasureSpecification unrestrictedMeasureSpec = new MeasureSpecification( heightMeasureSpec.Size, MeasureSpecification.ModeType.Unspecified);
+ MeasureSpecification unrestrictedMeasureSpec = new MeasureSpecification(heightMeasureSpec.Size, MeasureSpecification.ModeType.Unspecified);
if (scrollingDirection == Direction.Vertical)
{
- MeasureChild( childLayout, widthMeasureSpec, unrestrictedMeasureSpec ); // Height unrestricted by parent
+ MeasureChild(childLayout, widthMeasureSpec, unrestrictedMeasureSpec); // Height unrestricted by parent
}
else
{
- MeasureChild( childLayout, unrestrictedMeasureSpec, heightMeasureSpec ); // Width unrestricted by parent
+ MeasureChild(childLayout, unrestrictedMeasureSpec, heightMeasureSpec); // Width unrestricted by parent
}
float childWidth = childLayout.MeasuredWidth.Size.AsDecimal();
totalHeight = heightSizeAndState.Size.AsDecimal();
// Ensure layout respects it's given minimum size
- totalWidth = Math.Max( totalWidth, SuggestedMinimumWidth.AsDecimal() );
- totalHeight = Math.Max( totalHeight, SuggestedMinimumHeight.AsDecimal() );
+ totalWidth = Math.Max(totalWidth, SuggestedMinimumWidth.AsDecimal());
+ totalHeight = Math.Max(totalHeight, SuggestedMinimumHeight.AsDecimal());
widthSizeAndState.State = childWidthState;
heightSizeAndState.State = childHeightState;
- SetMeasuredDimensions( ResolveSizeAndState( new LayoutLength(totalWidth + Padding.Start + Padding.End), widthMeasureSpec, childWidthState ),
- ResolveSizeAndState( new LayoutLength(totalHeight + Padding.Top + Padding.Bottom), heightMeasureSpec, childHeightState ) );
+ SetMeasuredDimensions(ResolveSizeAndState(new LayoutLength(totalWidth + Padding.Start + Padding.End), widthMeasureSpec, childWidthState),
+ ResolveSizeAndState(new LayoutLength(totalHeight + Padding.Top + Padding.Bottom), heightMeasureSpec, childHeightState));
// Size of ScrollableBase is changed. Change Page width too.
scrollableBase.mPageWidth = (int)MeasuredWidth.Size.AsRoundedValue();
protected override void OnLayout(bool changed, LayoutLength left, LayoutLength top, LayoutLength right, LayoutLength bottom)
{
- foreach( LayoutItem childLayout in LayoutChildren )
+ foreach (LayoutItem childLayout in LayoutChildren)
{
- if( childLayout != null )
+ if (childLayout != null)
{
LayoutLength childWidth = childLayout.MeasuredWidth.Size;
LayoutLength childHeight = childLayout.MeasuredHeight.Size;
LayoutLength childLeft = new LayoutLength(childPosition.X + childMargin.Start + padding.Start);
LayoutLength childTop = new LayoutLength(childPosition.Y + childMargin.Top + padding.Top);
- childLayout.Layout( childLeft, childTop, childLeft + childWidth, childTop + childHeight );
+ childLayout.Layout(childLeft, childTop, childLeft + childWidth, childTop + childHeight);
}
}
}
}
set
{
- if(value != mScrollingDirection)
+ if (value != mScrollingDirection)
{
mScrollingDirection = value;
mPanGestureDetector.RemoveDirection(value == Direction.Horizontal ? PanGestureDetector.DirectionVertical : PanGestureDetector.DirectionHorizontal);
if (value != mScrollEnabled)
{
mScrollEnabled = value;
- if(mScrollEnabled)
+ if (mScrollEnabled)
{
mPanGestureDetector.Detected += OnPanGestureDetected;
mTapGestureDetector.Detected += OnTapGestureDetected;
/// </summary>
/// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
[EditorBrowsable(EditorBrowsableState.Never)]
- public Rectangle ScrollAvailableArea { set; get; }
+ public Vector2 ScrollAvailableArea { set; get; }
/// <summary>
/// ScrollEventArgs is a class to record scroll event arguments which will sent to user.
private TapGestureDetector mTapGestureDetector;
private View mScrollingChild;
private View mInterruptTouchingChild;
- private float multiplier =1.0f;
+ private float multiplier = 1.0f;
private bool scrolling = false;
private float ratioOfScreenWidthToCompleteScroll = 0.5f;
private float totalDisplacementForPan = 0.0f;
// If false then can only flick pages when the current animation/scroll as ended.
private bool flickWhenAnimating = false;
private PropertyNotification propertyNotification;
+ protected float finalTargetPosition;
/// <summary>
/// [Draft] Constructor
BackgroundColor = Color.Transparent,
};
- mInterruptTouchingChild.TouchEvent += (object source, View.TouchEventArgs args) => {
+ mInterruptTouchingChild.TouchEvent += (object source, View.TouchEventArgs args) =>
+ {
return true;
};
[EditorBrowsable(EditorBrowsableState.Never)]
public override void OnChildAdd(View view)
{
- if(view.Name != "InterruptTouchingChild")
+ if (view.Name != "InterruptTouchingChild")
{
- if(mScrollingChild.Name != "DefaultScrollingChild")
+ if (mScrollingChild.Name != "DefaultScrollingChild")
{
propertyNotification.Notified -= OnPropertyChanged;
mScrollingChild.RemovePropertyNotification(propertyNotification);
[EditorBrowsable(EditorBrowsableState.Never)]
public override void OnChildRemove(View view)
{
- if(view.Name != "InterruptTouchingChild")
+ if (view.Name != "InterruptTouchingChild")
{
propertyNotification.Notified -= OnPropertyChanged;
mScrollingChild.RemovePropertyNotification(propertyNotification);
}
}
-
/// <summary>
/// Scrolls to the item at the specified index.
/// </summary>
[EditorBrowsable(EditorBrowsableState.Never)]
public void ScrollToIndex(int index)
{
- if(mScrollingChild.ChildCount-1 < index || index < 0)
+ if (mScrollingChild.ChildCount - 1 < index || index < 0)
{
return;
}
- if(SnapToPage)
+ if (SnapToPage)
{
CurrentPage = index;
}
ScrollAnimationEndEvent?.Invoke(this, eventArgs);
}
+ private bool readyToNotice = false;
+
+ protected float noticeAnimationEndBeforePosition = 0.0f;
+
private void OnScroll()
{
ScrollEventArgs eventArgs = new ScrollEventArgs(mScrollingChild.CurrentPosition);
ScrollEvent?.Invoke(this, eventArgs);
+
+ CheckPreReachedTargetPosition();
+ }
+
+ private void CheckPreReachedTargetPosition()
+ {
+ // Check whether we reached pre-reached target position
+ if (readyToNotice &&
+ mScrollingChild.CurrentPosition.Y <= finalTargetPosition + noticeAnimationEndBeforePosition &&
+ mScrollingChild.CurrentPosition.Y >= finalTargetPosition - noticeAnimationEndBeforePosition)
+ {
+ //Notice first
+ readyToNotice = false;
+ OnPreReachedTargetPosition(finalTargetPosition);
+ }
+ }
+
+ /// <summary>
+ /// This helps developer who wants to know before scroll is reaching target position.
+ /// </summary>
+ /// <param name="targetPosition">Index of item.</param>
+ /// <since_tizen> 6 </since_tizen>
+ /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
+ [EditorBrowsable(EditorBrowsableState.Never)]
+ protected virtual void OnPreReachedTargetPosition(float targetPosition)
+ {
+
}
private void StopScroll()
private void AnimateChildTo(int duration, float axisPosition)
{
Debug.WriteLineIf(LayoutDebugScrollableBase, "AnimationTo Animation Duration:" + duration + " Destination:" + axisPosition);
+ finalTargetPosition = axisPosition;
StopScroll(); // Will replace previous animation so will stop existing one.
scrollAnimation.Play();
}
+ /// <summary>
+ /// Scroll to specific position with or without animation.
+ /// </summary>
+ /// <param name="position">Destination.</param>
+ /// <param name="animate">Scroll with or without animation</param>
+ [EditorBrowsable(EditorBrowsableState.Never)]
+ public void ScrollTo(float position, bool animate)
+ {
+ float currentPositionX = mScrollingChild.CurrentPosition.X != 0 ? mScrollingChild.CurrentPosition.X : mScrollingChild.Position.X;
+ float currentPositionY = mScrollingChild.CurrentPosition.Y != 0 ? mScrollingChild.CurrentPosition.Y : mScrollingChild.Position.Y;
+ float delta = ScrollingDirection == Direction.Horizontal ? currentPositionX : currentPositionY;
+ delta -= position;
+
+ ScrollBy(delta, animate);
+ }
+
+ private float BoundScrollPosition(float targetPosition)
+ {
+ if (ScrollAvailableArea != null)
+ {
+ float minScrollPosition = ScrollAvailableArea.X;
+ float maxScrollPosition = ScrollAvailableArea.Y;
+
+ targetPosition = Math.Min(-minScrollPosition, targetPosition);
+ targetPosition = Math.Max(-maxScrollPosition, targetPosition);
+ }
+ else
+ {
+ targetPosition = Math.Min(0, targetPosition);
+ targetPosition = Math.Max(-maxScrollDistance, targetPosition);
+ }
+
+ return targetPosition;
+ }
+
private void ScrollBy(float displacement, bool animate)
{
- if (GetChildCount() == 0 || displacement == 0 || maxScrollDistance < 0)
+ if (GetChildCount() == 0 || maxScrollDistance < 0)
{
return;
}
- float childCurrentPosition = (ScrollingDirection == Direction.Horizontal) ? mScrollingChild.PositionX: mScrollingChild.PositionY;
+ float childCurrentPosition = (ScrollingDirection == Direction.Horizontal) ? mScrollingChild.PositionX : mScrollingChild.PositionY;
Debug.WriteLineIf(LayoutDebugScrollableBase, "ScrollBy childCurrentPosition:" + childCurrentPosition +
" displacement:" + displacement,
- " maxScrollDistance:" + maxScrollDistance );
+ " maxScrollDistance:" + maxScrollDistance);
childTargetPosition = childCurrentPosition + displacement; // child current position + gesture displacement
- if(ScrollAvailableArea != null)
- {
- float minScrollPosition = ScrollingDirection == Direction.Horizontal? ScrollAvailableArea.X:ScrollAvailableArea.Y;
- float maxScrollPosition = ScrollingDirection == Direction.Horizontal?
- ScrollAvailableArea.X + ScrollAvailableArea.Width:
- ScrollAvailableArea.Y + ScrollAvailableArea.Height;
- childTargetPosition = Math.Min( -minScrollPosition, childTargetPosition );
- childTargetPosition = Math.Max( -maxScrollPosition, childTargetPosition );
- }
- else
- {
- childTargetPosition = Math.Min(0, childTargetPosition);
- childTargetPosition = Math.Max(-maxScrollDistance, childTargetPosition);
- }
-
- Debug.WriteLineIf( LayoutDebugScrollableBase, "ScrollBy currentAxisPosition:" + childCurrentPosition + "childTargetPosition:" + childTargetPosition);
+ Debug.WriteLineIf(LayoutDebugScrollableBase, "ScrollBy currentAxisPosition:" + childCurrentPosition + "childTargetPosition:" + childTargetPosition);
if (animate)
{
// Calculate scroll animaton duration
float scrollDistance = Math.Abs(displacement);
- int duration = (int)((320*FlickAnimationSpeed) + (scrollDistance * FlickAnimationSpeed));
+ int duration = (int)((320 * FlickAnimationSpeed) + (scrollDistance * FlickAnimationSpeed));
Debug.WriteLineIf(LayoutDebugScrollableBase, "Scroll Animation Duration:" + duration + " Distance:" + scrollDistance);
- AnimateChildTo(duration, childTargetPosition);
+ readyToNotice = true;
+
+ AnimateChildTo(duration, BoundScrollPosition(AdjustTargetPositionOfScrollAnimation(BoundScrollPosition(childTargetPosition))));
}
else
{
+ finalTargetPosition = BoundScrollPosition(childTargetPosition);
+
// Set position of scrolling child without an animation
if (ScrollingDirection == Direction.Horizontal)
{
- mScrollingChild.PositionX = childTargetPosition;
+ mScrollingChild.PositionX = finalTargetPosition;
}
else
{
- mScrollingChild.PositionY = childTargetPosition;
+ mScrollingChild.PositionY = finalTargetPosition;
}
+
}
}
float flickDisplacement = 0.0f;
- float speed = Math.Min(4.0f,Math.Abs(axisVelocity));
+ float speed = Math.Min(4.0f, Math.Abs(axisVelocity));
Debug.WriteLineIf(LayoutDebugScrollableBase, "ScrollableBase Candidate Flick speed:" + speed);
if (speed > FlickThreshold)
{
// Flick length is the length of the ScrollableBase.
- float flickLength = (ScrollingDirection == Direction.Horizontal) ?CurrentSize.Width:CurrentSize.Height;
+ float flickLength = (ScrollingDirection == Direction.Horizontal) ? CurrentSize.Width : CurrentSize.Height;
// Calculate multiplier by mapping speed between the multiplier minimum and maximum.
- multiplier =( (speed - speedMinimum) / ( (speedMaximum - speedMinimum) * (multiplierMaximum - multiplierMinimum) ) )+ multiplierMinimum;
+ multiplier = ((speed - speedMinimum) / ((speedMaximum - speedMinimum) * (multiplierMaximum - multiplierMinimum))) + multiplierMinimum;
// flick displacement is the product of the flick length and multiplier
flickDisplacement = ((flickLength * multiplier) * speed) / axisVelocity; // *speed and /velocity to perserve sign.
- Debug.WriteLineIf(LayoutDebugScrollableBase, "Calculated FlickDisplacement[" + flickDisplacement +"] from speed[" + speed + "] multiplier:"
+ Debug.WriteLineIf(LayoutDebugScrollableBase, "Calculated FlickDisplacement[" + flickDisplacement + "] from speed[" + speed + "] multiplier:"
+ multiplier);
}
return flickDisplacement;
" parent length:" + scrollerLength +
" scrolling child length:" + scrollingChildLength);
- return Math.Max(scrollingChildLength - scrollerLength,0);
+ return Math.Max(scrollingChildLength - scrollerLength, 0);
}
private void PageSnap()
{
Debug.WriteLineIf(LayoutDebugScrollableBase, "PageSnap with pan candidate totalDisplacement:" + totalDisplacementForPan +
- " currentPage[" + CurrentPage + "]" );
+ " currentPage[" + CurrentPage + "]");
//Increment current page if total displacement enough to warrant a page change.
if (Math.Abs(totalDisplacementForPan) > (mPageWidth * ratioOfScreenWidthToCompleteScroll))
{
if (totalDisplacementForPan < 0)
{
- CurrentPage = Math.Min(Math.Max(mScrollingChild.Children.Count - 1,0), ++CurrentPage);
+ CurrentPage = Math.Min(Math.Max(mScrollingChild.Children.Count - 1, 0), ++CurrentPage);
}
else
{
}
// Animate to new page or reposition to current page
- float destinationX = -(mScrollingChild.Children[CurrentPage].Position.X + mScrollingChild.Children[CurrentPage].CurrentSize.Width/2 - CurrentSize.Width/2); // set to middle of current page
+ float destinationX = -(mScrollingChild.Children[CurrentPage].Position.X + mScrollingChild.Children[CurrentPage].CurrentSize.Width / 2 - CurrentSize.Width / 2); // set to middle of current page
Debug.WriteLineIf(LayoutDebugScrollableBase, "Snapping to page[" + CurrentPage + "] to:" + destinationX + " from:" + mScrollingChild.PositionX);
AnimateChildTo(ScrollDuration, destinationX);
}
private void Flick(float flickDisplacement)
{
- if (SnapToPage)
- {
- if ( ( flickWhenAnimating && scrolling == true) || ( scrolling == false) )
- {
- if(flickDisplacement < 0)
- {
- CurrentPage = Math.Min(Math.Max(mScrollingChild.Children.Count - 1,0), CurrentPage + 1);
- Debug.WriteLineIf(LayoutDebugScrollableBase, "Snap - to page:" + CurrentPage);
- }
- else
- {
- CurrentPage = Math.Max(0, CurrentPage - 1);
- Debug.WriteLineIf(LayoutDebugScrollableBase, "Snap + to page:" + CurrentPage);
- }
-
- float destinationX = -(mScrollingChild.Children[CurrentPage].Position.X + mScrollingChild.Children[CurrentPage].CurrentSize.Width/2.0f - CurrentSize.Width/2.0f); // set to middle of current page
- Debug.WriteLineIf(LayoutDebugScrollableBase, "Snapping to :" + destinationX);
- AnimateChildTo(ScrollDuration, destinationX);
- }
- }
- else
- {
- ScrollBy(flickDisplacement, true); // Animate flickDisplacement.
- }
+ if (SnapToPage)
+ {
+ if ((flickWhenAnimating && scrolling == true) || (scrolling == false))
+ {
+ if (flickDisplacement < 0)
+ {
+ CurrentPage = Math.Min(Math.Max(mScrollingChild.Children.Count - 1, 0), CurrentPage + 1);
+ Debug.WriteLineIf(LayoutDebugScrollableBase, "Snap - to page:" + CurrentPage);
+ }
+ else
+ {
+ CurrentPage = Math.Max(0, CurrentPage - 1);
+ Debug.WriteLineIf(LayoutDebugScrollableBase, "Snap + to page:" + CurrentPage);
+ }
+
+ float destinationX = -(mScrollingChild.Children[CurrentPage].Position.X + mScrollingChild.Children[CurrentPage].CurrentSize.Width / 2.0f - CurrentSize.Width / 2.0f); // set to middle of current page
+ Debug.WriteLineIf(LayoutDebugScrollableBase, "Snapping to :" + destinationX);
+ AnimateChildTo(ScrollDuration, destinationX);
+ }
+ }
+ else
+ {
+ ScrollBy(flickDisplacement, true); // Animate flickDisplacement.
+ }
}
private void OnPanGestureDetected(object source, PanGestureDetector.DetectedEventArgs e)
{
PageSnap();
}
+ else
+ {
+ ScrollBy(0, true);
+ }
}
totalDisplacementForPan = 0;
{
// Stop scrolling if tap detected (press then relase).
// Unless in Pages mode, do not want a page change to stop part way.
- if(scrolling && !SnapToPage)
+ if (scrolling && !SnapToPage)
{
StopScroll();
}
private void ScrollAnimationFinished(object sender, EventArgs e)
{
scrolling = false;
+ CheckPreReachedTargetPosition();
OnScrollAnimationEnd();
}
+
+ /// <summary>
+ /// Adjust scrolling position by own scrolling rules.
+ /// Override this function when developer wants to change destination of flicking.(e.g. always snap to center of item)
+ /// </summary>
+ /// <since_tizen> 6 </since_tizen>
+ /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
+ [EditorBrowsable(EditorBrowsableState.Never)]
+ protected virtual float AdjustTargetPositionOfScrollAnimation(float position)
+ {
+ return position;
+ }
+
}
} // namespace