protected override void OnMeasure(MeasureSpecification widthMeasureSpec, MeasureSpecification heightMeasureSpec)
{
flagOnMeasureOverride = true;
base.OnMeasure(widthMeasureSpec, heightMeasureSpec);
}
protected override void OnMeasure(MeasureSpecification widthMeasureSpec, MeasureSpecification heightMeasureSpec)
{
Extents padding = Padding;
float totalHeight = padding.Top + padding.Bottom;
float totalWidth = padding.Start + padding.End;
MeasuredSize.StateType childWidthState = MeasuredSize.StateType.MeasuredSizeOK;
MeasuredSize.StateType childHeightState = MeasuredSize.StateType.MeasuredSizeOK;
Direction scrollingDirection = Direction.Vertical;
ScrollableBase scrollableBase = this.Owner as ScrollableBase;
if (scrollableBase)
{
scrollingDirection = scrollableBase.ScrollingDirection;
}
// measure child, should be a single scrolling child
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);
if (scrollingDirection == Direction.Vertical)
{
MeasureChildWithMargins(childLayout, widthMeasureSpec, new LayoutLength(0), unrestrictedMeasureSpec, new LayoutLength(0)); // Height unrestricted by parent
}
else
{
MeasureChildWithMargins(childLayout, unrestrictedMeasureSpec, new LayoutLength(0), heightMeasureSpec, new LayoutLength(0)); // Width unrestricted by parent
}
float childWidth = childLayout.MeasuredWidth.Size.AsDecimal();
float childHeight = childLayout.MeasuredHeight.Size.AsDecimal();
// Determine the width and height needed by the children using their given position and size.
// Children could overlap so find the left most and right most child.
Position2D childPosition = childLayout.Owner.Position2D;
float childLeft = childPosition.X;
float childTop = childPosition.Y;
// Store current width and height needed to contain all children.
Extents childMargin = childLayout.Margin;
totalWidth = childWidth + childMargin.Start + childMargin.End;
totalHeight = childHeight + childMargin.Top + childMargin.Bottom;
if (childLayout.MeasuredWidth.State == MeasuredSize.StateType.MeasuredSizeTooSmall)
{
childWidthState = MeasuredSize.StateType.MeasuredSizeTooSmall;
}
if (childLayout.MeasuredHeight.State == MeasuredSize.StateType.MeasuredSizeTooSmall)
{
childHeightState = MeasuredSize.StateType.MeasuredSizeTooSmall;
}
}
}
MeasuredSize widthSizeAndState = ResolveSizeAndState(new LayoutLength(totalWidth + Padding.Start + Padding.End), widthMeasureSpec, MeasuredSize.StateType.MeasuredSizeOK);
MeasuredSize heightSizeAndState = ResolveSizeAndState(new LayoutLength(totalHeight + Padding.Top + Padding.Bottom), heightMeasureSpec, MeasuredSize.StateType.MeasuredSizeOK);
totalWidth = widthSizeAndState.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());
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));
// Size of ScrollableBase is changed. Change Page width too.
scrollableBase.mPageWidth = (int)MeasuredWidth.Size.AsRoundedValue();
}
public void OnMeasureTest(MeasureSpecification widthMeasureSpec, MeasureSpecification heightMeasureSpec)
{
OnMeasure(widthMeasureSpec, heightMeasureSpec);
}
public void MeasureChildrenTest(MeasureSpecification widthMeasureSpec, MeasureSpecification heightMeasureSpec)
{
MeasureChildren(widthMeasureSpec, heightMeasureSpec);
}
public void LinearLayoutOnMeasure()
{
tlog.Debug(tag, $"LinearLayoutOnMeasure START");
flagOnMeasureOverride = false;
Assert.False(flagOnMeasureOverride, "flagOnMeasureOverride should be false initial");
LayoutItem layoutItem = new LinearLayout();
View view = new View()
{
ExcludeLayouting = false,
Weight = 10,
WidthSpecification = 0,
HeightSpecification = 0,
Layout = new LinearLayout()
};
layoutItem.AttachToOwner(view);
var testingTarget = new MyLinearLayout();
Assert.IsNotNull(testingTarget, "null handle returned");
Assert.IsInstanceOf <LinearLayout>(testingTarget, "Should be an instance of LinearLayout type.");
testingTarget.AttachToOwner(view);
testingTarget.Add(layoutItem);
MeasureSpecification measureWidth = new MeasureSpecification(new LayoutLength(50.0f), MeasureSpecification.ModeType.Exactly);
MeasureSpecification measureHeight = new MeasureSpecification(new LayoutLength(50.0f), MeasureSpecification.ModeType.Exactly);
/**
* isExactly is true
* useExcessSpace is true :(childLayout.Owner.WidthSpecification == 0) && (childWeight > 0)
*/
testingTarget.OnMeasureTest(measureWidth, measureHeight);
Assert.True(flagOnMeasureOverride, "LinearLayout overridden method not invoked.");
/**
* isExactly is false
* useExcessSpace is true :(childLayout.Owner.WidthSpecification == 0) && (childWeight > 0)
*/
flagOnMeasureOverride = false;
Assert.False(flagOnMeasureOverride, "flagOnMeasureOverride should be false initial");
MeasureSpecification measureWidth2 = new MeasureSpecification(new LayoutLength(50.0f), MeasureSpecification.ModeType.AtMost);
MeasureSpecification measureHeight2 = new MeasureSpecification(new LayoutLength(50.0f), MeasureSpecification.ModeType.Unspecified);
testingTarget.OnMeasureTest(measureWidth2, measureHeight2);
Assert.True(flagOnMeasureOverride, "LinearLayout overridden method not invoked.");
/**
* matchHeight
* heightMode != MeasureSpecification.ModeType.Exactly && childDesiredHeight == LayoutParamPolicies.MatchParent
*/
view.HeightSpecification = LayoutParamPolicies.MatchParent;
testingTarget.OnMeasureTest(measureWidth2, measureHeight2);
/**Test LinearLayout.Orientation.Vertical */
testingTarget.LinearOrientation = LinearLayout.Orientation.Vertical;
view.HeightSpecification = 0;
flagOnMeasureOverride = false;
Assert.False(flagOnMeasureOverride, "flagOnMeasureOverride should be false initial");
/**
* isExactly is true
* useExcessSpace is true :(childLayout.Owner.HeightSpecification == 0) && (childWeight > 0)
*/
testingTarget.OnMeasureTest(measureWidth, measureHeight);
Assert.True(flagOnMeasureOverride, "LinearLayout overridden method not invoked.");
flagOnMeasureOverride = false;
Assert.False(flagOnMeasureOverride, "flagOnMeasureOverride should be false initial");
/**
* isExactly is true
* useExcessSpace is true :(childLayout.Owner.HeightSpecification == 0) && (childWeight > 0)
*
* matchWidth
* widthMode != MeasureSpecification.ModeType.Exactly && childDesiredWidth == LayoutParamPolicies.MatchParent
*/
view.WidthSpecification = LayoutParamPolicies.MatchParent;
testingTarget.OnMeasureTest(measureWidth2, measureHeight2);
Assert.True(flagOnMeasureOverride, "LinearLayout overridden method not invoked.");
testingTarget.Dispose();
tlog.Debug(tag, $"LinearLayoutOnMeasure END (OK)");
}
public void MeasureChildTest(LayoutItem child, MeasureSpecification parentWidth, MeasureSpecification parentHeight)
{
MeasureChild(child, parentWidth, parentHeight);
}
protected override void MeasureChild(LayoutItem child, MeasureSpecification parentWidth, MeasureSpecification parentHeight)
{
flagOnMeasureChild = true;
base.MeasureChild(child, parentWidth, parentHeight);
}
public void MeasureChildWithoutPaddingTest(LayoutItem child, MeasureSpecification parentWidthMeasureSpec, MeasureSpecification parentHeightMeasureSpec)
{
MeasureChildWithoutPadding(child, parentWidthMeasureSpec, parentHeightMeasureSpec);
}
protected override void MeasureChildWithMargins(LayoutItem child, MeasureSpecification parentWidthMeasureSpec, LayoutLength widthUsed, MeasureSpecification parentHeightMeasureSpec, LayoutLength heightUsed)
{
flagOnMeasureChild = true;
base.MeasureChildWithMargins(child, parentWidthMeasureSpec, widthUsed, parentHeightMeasureSpec, heightUsed);
}
public void MeasureChildWithMarginsTest(LayoutItem child, MeasureSpecification parentWidthMeasureSpec, LayoutLength widthUsed, MeasureSpecification parentHeightMeasureSpec, LayoutLength heightUsed)
{
MeasureChildWithMargins(child, parentWidthMeasureSpec, widthUsed, parentHeightMeasureSpec, heightUsed);
}
protected override void MeasureChildren(MeasureSpecification widthMeasureSpec, MeasureSpecification heightMeasureSpec)
{
flagOnMeasureChild = true;
base.MeasureChildren(widthMeasureSpec, heightMeasureSpec);
}
public MeasuredSize ResolveSizeAndState(LayoutLength size, MeasureSpecification measureSpecification, MeasuredSize.StateType childMeasuredState)
{
return(base.ResolveSizeAndState(size, measureSpecification, childMeasuredState));
}
