private void ApplyGravityToLine(LineDefinition line)
{
int viewCount = line.Views.Count;
if (viewCount <= 0)
{
return;
}
float totalWeight = 0;
foreach (View prev in line.Views)
{
CustomLayoutParams plp = (CustomLayoutParams)prev.LayoutParameters;
totalWeight += this.GetWeight(plp);
}
View lastChild = line.Views[viewCount - 1];
CustomLayoutParams lastChildLayoutParams = (CustomLayoutParams)lastChild.LayoutParameters;
int excessLength = line.LineLength - (lastChildLayoutParams.Length + lastChildLayoutParams.InlineStartLength);
int excessOffset = 0;
foreach (View child in line.Views)
{
CustomLayoutParams layoutParams = (CustomLayoutParams)child.LayoutParameters;
float weight = this.GetWeight(layoutParams);
GravityFlags gravity = this.GetGravity(layoutParams);
int extraLength = (int)Math.Round((double)(excessLength * weight / totalWeight));
int childLength = layoutParams.Length + layoutParams.SpacingLength;
int childThickness = layoutParams.Thickness + layoutParams.SpacingThickness;
Rect container = new Rect();
container.Top = 0;
container.Left = excessOffset;
container.Right = childLength + extraLength + excessOffset;
container.Bottom = line.LineThickness;
Rect result = new Rect();
Android.Views.Gravity.Apply(gravity, childLength, childThickness, container, result);
excessOffset += extraLength;
layoutParams.InlineStartLength = result.Left + layoutParams.InlineStartLength;
layoutParams.InlineStartThickness = result.Top;
layoutParams.Length = result.Width() - layoutParams.SpacingLength;
layoutParams.Thickness = result.Height() - layoutParams.SpacingThickness;
}
}
private void ApplyPositionsToViews(LineDefinition line)
{
foreach (View child in line.Views)
{
CustomLayoutParams layoutParams = (CustomLayoutParams)child.LayoutParameters;
if (this.config.Orientation == HORIZONTAL)
{
layoutParams.SetPosition(this.PaddingLeft + line.LineStartLength + layoutParams.InlineStartLength, this.PaddingTop + line.LineStartThickness + layoutParams.InlineStartThickness);
child.Measure(MeasureSpec.MakeMeasureSpec(layoutParams.Length, MeasureSpecMode.Exactly), MeasureSpec.MakeMeasureSpec(layoutParams.Thickness, MeasureSpecMode.Exactly));
}
else
{
layoutParams.SetPosition(this.PaddingLeft + line.LineStartThickness + layoutParams.InlineStartThickness, this.PaddingTop + line.LineStartLength + layoutParams.InlineStartLength);
child.Measure(MeasureSpec.MakeMeasureSpec(layoutParams.Thickness, MeasureSpecMode.Exactly), MeasureSpec.MakeMeasureSpec(layoutParams.Length, MeasureSpecMode.Exactly));
}
}
}
private void ApplyGravityToLines(IList <LineDefinition> lines, int realControlLength, int realControlThickness)
{
int linesCount = lines.Count;
if (linesCount <= 0)
{
return;
}
int totalWeight = linesCount;
LineDefinition lastLine = lines[linesCount - 1];
int excessThickness = realControlThickness - (lastLine.LineThickness + lastLine.LineStartThickness);
int excessOffset = 0;
foreach (LineDefinition child in lines)
{
int weight = 1;
GravityFlags gravity = this.Gravity;
int extraThickness = (int)Math.Round((double)(excessThickness * weight / totalWeight));
int childLength = child.LineLength;
int childThickness = child.LineThickness;
Rect container = new Rect();
container.Top = excessOffset;
container.Left = 0;
container.Right = realControlLength;
container.Bottom = childThickness + extraThickness + excessOffset;
Rect result = new Rect();
Android.Views.Gravity.Apply(gravity, childLength, childThickness, container, result);
excessOffset += extraThickness;
child.AddLineStartLength(result.Left);
child.AddLineStartThickness(result.Top);
child.Length = result.Width();
child.Thickness = result.Height();
}
}
protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
int sizeWidth = MeasureSpec.GetSize(widthMeasureSpec) - this.PaddingRight - this.PaddingLeft;
int sizeHeight = MeasureSpec.GetSize(heightMeasureSpec) - this.PaddingTop - this.PaddingBottom;
MeasureSpecMode modeWidth = MeasureSpec.GetMode(widthMeasureSpec);
MeasureSpecMode modeHeight = MeasureSpec.GetMode(heightMeasureSpec);
int controlMaxLength = this.config.Orientation == HORIZONTAL ? sizeWidth : sizeHeight;
int controlMaxThickness = this.config.Orientation == HORIZONTAL ? sizeHeight : sizeWidth;
MeasureSpecMode modeLength = this.config.Orientation == HORIZONTAL ? modeWidth : modeHeight;
MeasureSpecMode modeThickness = this.config.Orientation == HORIZONTAL ? modeHeight : modeWidth;
lines.Clear();
LineDefinition currentLine = new LineDefinition(controlMaxLength, config);
lines.Add(currentLine);
int count = this.ChildCount;
for (int i = 0; i < count; i++)
{
View child = this.GetChildAt(i);
if (child.Visibility == ViewStates.Gone)
{
continue;
}
CustomLayoutParams lp = (CustomLayoutParams)child.LayoutParameters;
child.Measure(GetChildMeasureSpec(widthMeasureSpec, this.PaddingLeft + this.PaddingRight, lp.Width), GetChildMeasureSpec(heightMeasureSpec, this.PaddingTop + this.PaddingBottom, lp.Height));
lp.ClearCalculatedFields(this.config.Orientation);
if (this.config.Orientation == FlowLayout.HORIZONTAL)
{
lp.Length = child.MeasuredWidth;
lp.Thickness = child.MeasuredHeight;
}
else
{
lp.Length = child.MeasuredHeight;
lp.Thickness = child.MeasuredWidth;
}
bool newLine = lp.newLine || (modeLength != MeasureSpecMode.Unspecified && !currentLine.CanFit(child));
if (newLine)
{
currentLine = new LineDefinition(controlMaxLength, config);
if (this.config.Orientation == VERTICAL && this.config.Direction == LAYOUT_DIRECTION_RTL)
{
lines.Insert(0, currentLine);
}
else
{
lines.Add(currentLine);
}
}
if (this.config.Orientation == HORIZONTAL && this.config.Direction == LAYOUT_DIRECTION_RTL)
{
currentLine.AddView(0, child);
}
else
{
currentLine.AddView(child);
}
}
this.CalculateLinesAndChildPosition(lines);
int contentLength = 0;
foreach (LineDefinition l in lines)
{
contentLength = Math.Max(contentLength, l.LineLength);
}
int contentThickness = currentLine.LineStartThickness + currentLine.LineThickness;
int realControlLength = this.FindSize(modeLength, controlMaxLength, contentLength);
int realControlThickness = this.FindSize(modeHeight, controlMaxThickness, contentThickness);
this.ApplyGravityToLines(lines, realControlLength, realControlThickness);
foreach (LineDefinition line in lines)
{
this.ApplyGravityToLine(line);
this.ApplyPositionsToViews(line);
}
/* need to take padding into account */
int totalControlWidth = this.PaddingLeft + this.PaddingRight;
int totalControlHeight = this.PaddingBottom + this.PaddingTop;
if (this.config.Orientation == HORIZONTAL)
{
totalControlWidth += contentLength;
totalControlHeight += contentThickness;
}
else
{
totalControlWidth += contentThickness;
totalControlHeight += contentLength;
}
this.SetMeasuredDimension(ResolveSize(totalControlWidth, widthMeasureSpec), ResolveSize(totalControlHeight, heightMeasureSpec));
}