/// <summary>
/// Sets the specified <see cref="Binding"/> instance for the object.
/// </summary>
/// <param name="obj">The target object.</param>
/// <param name="binding">The <see cref="Binding"/> instance to be set.</param>
/// <exception cref="ArgumentNullException">Thrown when <paramref name="binding"/> is <c>null</c>.</exception>
public static void SetBinding(this IPairable obj, Binding binding)
{
var notifier = obj as INotifyPropertyChanged ?? obj.Pair as INotifyPropertyChanged;
if (notifier != null)
{
notifier.SetBinding(binding);
}
}
/// <summary>
/// Removes any bindings from the object that are currently targeting the property at the specified target path.
/// </summary>
/// <param name="obj">The object.</param>
/// <param name="targetPath">The path to the property that is to be cleared of any bindings.</param>
public static void ClearBinding(this IPairable obj, string targetPath)
{
var notifier = obj as INotifyPropertyChanged ?? obj.Pair as INotifyPropertyChanged;
if (notifier != null)
{
notifier.ClearBinding(targetPath);
}
}
/// <summary>
/// Removes every binding where the object is either the target or the source.
/// </summary>
/// <param name="obj">The object.</param>
public static void ClearAllBindings(this IPairable obj)
{
var notifier = obj as INotifyPropertyChanged ?? obj.Pair as INotifyPropertyChanged;
if (notifier != null)
{
notifier.ClearAllBindings();
}
}
public static void OnPropertyChanged(this IPairable obj, [CallerMemberName] string propertyName = null)
{
var jObject = obj as Java.Lang.Object;
if (obj is INotifyPropertyChanged && (jObject == null || jObject.Handle != IntPtr.Zero))
{
obj.RaiseEvent(nameof(INotifyPropertyChanged.PropertyChanged), new PropertyChangedEventArgs(propertyName));
}
}
/// <summary>
/// Returns the value of the property or field with the specified <paramref name="name"/>.
/// </summary>
/// <param name="obj">The object.</param>
/// <param name="name">The name of the property or field whose value is to be returned.</param>
/// <param name="index">Optional index values for indexed properties. This value should be <c>null</c> for non-indexed properties.</param>
public static object GetValue(this IPairable obj, string name, object[] index)
{
if (obj == null)
{
return(null);
}
var type = obj.GetType();
var property = Device.Reflector.GetProperty(type, name);
if (property != null)
{
return(property.GetValue(obj, index));
}
var field = Device.Reflector.GetField(type, name);
if (field != null)
{
return(field.GetValue(obj));
}
var pairable = obj as IPairable;
if (pairable == null || pairable.Pair == null)
{
return(null);
}
obj = pairable.Pair;
type = obj.GetType();
property = Device.Reflector.GetProperty(type, name);
if (property != null)
{
return(property.GetValue(obj, index));
}
field = Device.Reflector.GetField(type, name);
if (field != null)
{
return(field.GetValue(obj));
}
return(null);
}
internal static bool RaiseEvent(this IPairable obj, string eventName, EventArgs args)
{
var type = obj.GetType();
var evt = type.GetEvent(eventName, BindingFlags.Instance | BindingFlags.Public);
if (evt != null)
{
var attribute = evt.GetCustomAttributes <EventDelegateAttribute>().FirstOrDefault();
if (attribute != null)
{
eventName = attribute.DelegateName;
}
FieldInfo info = null;
do
{
info = type.GetField(eventName, BindingFlags.Instance | BindingFlags.NonPublic);
type = type.BaseType;
}while (info == null && type != null);
if (info != null)
{
var del = info.GetValue(obj) as MulticastDelegate;
if (del != null)
{
var invocationList = del.GetInvocationList();
foreach (var method in invocationList)
{
method.Method.Invoke(method.Target, new object[] { obj.Pair ?? obj, EventArgs.Empty });
}
return(true);
}
}
}
return(false);
}
/// <summary>
/// Attempts to raise the event with the specified name and <see cref="EventArgs"/> on the current instance.
/// </summary>
/// <param name="obj">The current object.</param>
/// <param name="eventName">The name of the event to be raised.</param>
/// <param name="args">The <see cref="EventArgs"/> instance containing the event data.</param>
/// <returns><c>true</c> if the event is successfully raised, otherwise <c>false</c>.</returns>
public static bool RaiseEvent(this IPairable obj, string eventName, EventArgs args)
{
if (obj == null)
{
return(false);
}
var type = obj.GetType();
var evt = Device.Reflector.GetEvent(type, eventName);
if (evt == null)
{
return(false);
}
var attribute = evt.GetCustomAttributes(typeof(EventDelegateAttribute), true).FirstOrDefault() as EventDelegateAttribute;
if (attribute != null)
{
eventName = attribute.DelegateName;
}
FieldInfo info;
do
{
info = Device.Reflector.GetField(type, eventName);
type = Device.Reflector.GetBaseType(type);
}while (info == null && type != null);
if (info == null && obj.Pair != null)
{
obj = obj.Pair;
type = obj.GetType();
evt = Device.Reflector.GetEvent(type, eventName);
if (evt == null)
{
return(false);
}
attribute = evt.GetCustomAttributes(typeof(EventDelegateAttribute), true).FirstOrDefault() as EventDelegateAttribute;
if (attribute != null)
{
eventName = attribute.DelegateName;
}
do
{
info = Device.Reflector.GetField(type, eventName);
type = Device.Reflector.GetBaseType(type);
}while (info == null && type != null);
}
if (info == null)
{
return(false);
}
var del = info.GetValue(obj) as MulticastDelegate;
if (del == null)
{
return(false);
}
var invocationList = del.GetInvocationList();
foreach (var method in invocationList)
{
method.Raise(obj, args);
}
return(true);
}
/// <summary>
/// Sets the value of the property or field with the specified <paramref name="name"/> when running on one of the specified <see cref="MobileTarget"/>s.
/// </summary>
/// <param name="obj">The object.</param>
/// <param name="name">The name the property or field whose value is to be set.</param>
/// <param name="value">The value to set to the property or field.</param>
/// <param name="index">Optional index values for indexed properties. This value should be <c>null</c> for non-indexed properties.</param>
/// <param name="targets">The targets on which the code must be running for the value to be set.</param>
public static void SetValue(this IPairable obj, string name, object value, object[] index, MobileTarget targets)
{
obj.SetValue(name, value, index, null, targets);
}
/// <summary>
/// Returns the value of the property or field with the specified <paramref name="name"/>.
/// </summary>
/// <param name="obj">The object.</param>
/// <param name="name">The name of the property or field whose value is to be returned.</param>
public static object GetValue(this IPairable obj, string name)
{
return(obj.GetValue(name, null));
}
/// <summary>
/// Sets the value of the property or field with the specified <paramref name="name"/> when running on one of the specified <see cref="MobileTarget"/>s.
/// </summary>
/// <param name="obj">The object.</param>
/// <param name="name">The name of the property or field whose value is to be set.</param>
/// <param name="value">The value to set to the property or field.</param>
/// <param name="index">Optional index values for indexed properties. This value should be <c>null</c> for non-indexed properties.</param>
/// <param name="converter">An optional converter to use on the value prior to setting the property or field.</param>
/// <param name="targets">The targets on which the code must be running for the value to be set.</param>
public static void SetValue(this IPairable obj, string name, object value, object[] index, IValueConverter converter, MobileTarget targets)
{
if (obj == null || !targets.HasFlag(iApp.Factory.Target))
{
return;
}
var type = obj.GetType();
try
{
var property = Device.Reflector.GetProperty(type, name);
if (property != null)
{
if (converter != null)
{
value = converter.Convert(value, property.PropertyType, null);
}
else
{
value = Binding.GetConvertedValue(value, property.PropertyType);
}
property.SetValue(obj, value, index);
return;
}
var field = Device.Reflector.GetField(type, name);
if (field != null)
{
if (converter != null)
{
value = converter.Convert(value, field.FieldType, null);
}
else
{
value = Binding.GetConvertedValue(value, field.FieldType);
}
field.SetValue(obj, value);
return;
}
if (obj != null && obj.Pair != null)
{
type = obj.Pair.GetType();
property = Device.Reflector.GetProperty(type, name);
if (property != null)
{
if (converter != null)
{
value = converter.Convert(value, property.PropertyType, null);
}
else
{
value = Binding.GetConvertedValue(value, property.PropertyType);
}
property.SetValue(obj.Pair, value, index);
return;
}
field = Device.Reflector.GetField(type, name);
if (field != null)
{
if (converter != null)
{
value = converter.Convert(value, field.FieldType, null);
}
else
{
value = Binding.GetConvertedValue(value, field.FieldType);
}
field.SetValue(obj.Pair, value);
}
}
}
catch (Exception e)
{
iApp.Log.Warn("Unable to set value of member on {0}.", e, obj.ToString());
}
}
/// <summary>
/// Sets the value of the property or field with the specified <paramref name="name"/> when running on one of the specified <see cref="MobileTarget"/>s.
/// </summary>
/// <param name="obj">The object.</param>
/// <param name="name">The name of the property or field whose value is to be set.</param>
/// <param name="value">The value to set to the property or field.</param>
/// <param name="converter">An optional converter to use on the value prior to setting the property or field.</param>
/// <param name="targets">The targets on which the code must be running for the value to be set.</param>
public static void SetValue(this IPairable obj, string name, object value, IValueConverter converter, MobileTarget targets)
{
obj.SetValue(name, value, null, converter, targets);
}
/// <summary>
/// Positions and sizes the children of a grid using the grid's columns and rows.
/// </summary>
/// <param name="grid">The grid object.</param>
/// <param name="minimumSize">The minimum size of the area in which the children are placed.</param>
/// <param name="maximumSize">The maximum size of the area in which the children are placed.</param>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="grid"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="minimumSize"/> or <paramref name="maximumSize"/> contains a negative value.</exception>
/// <exception cref="ArgumentException">Thrown when <paramref name="minimumSize"/> has an infinite width or height -or- when the width of <paramref name="maximumSize"/> is infinite and the grid contains at least one star-sized column -or- when the height of <paramref name="maximumSize"/> is infinite and the grid contains at least one star-sized row.</exception>
public static Size PerformLayout(this IGridBase grid, Size minimumSize, Size maximumSize)
{
if (grid == null)
{
throw new ArgumentNullException("grid");
}
#region ILayoutInstruction layout preprocessors
var instruction = grid as ILayoutInstruction;
if (instruction == null)
{
var pairable = grid as IPairable;
if (pairable != null)
{
instruction = pairable.Pair as ILayoutInstruction;
}
}
if (instruction != null)
{
iApp.Factory.Instructor.Layout(instruction);
IPairable pair = null;
var pairable = grid as IPairable;
if (pairable != null)
{
pair = pairable.Pair;
}
var cell = grid as IGridCell ?? pair as IGridCell;
if (cell != null)
{
minimumSize.Height = cell.MinHeight;
maximumSize.Height = cell.MaxHeight;
}
}
#endregion
maximumSize.Width = Math.Max(maximumSize.Width, minimumSize.Width);
maximumSize.Height = Math.Max(maximumSize.Height, minimumSize.Height);
if (double.IsInfinity(minimumSize.Width) || double.IsInfinity(minimumSize.Height))
{
throw new ArgumentException("Minimum size must not have an infinite width or height.", "minimumSize");
}
if (minimumSize.Width < 0 || minimumSize.Height < 0)
{
throw new ArgumentOutOfRangeException("minimumSize", "The given size must not contain any negative values.");
}
if (maximumSize.Width < 0 || maximumSize.Height < 0)
{
throw new ArgumentOutOfRangeException("maximumSize", "The given size must not contain any negative values.");
}
// if the grid has no rows or columns, provide one
var rows = grid.Rows.Count == 0 ? new List <Row> {
new Row(1, LayoutUnitType.Auto)
} : grid.Rows.ToList();
var columns = grid.Columns.Count == 0 ? new List <Column> {
new Column(1, LayoutUnitType.Auto)
} : grid.Columns.ToList();
#region Build index dictionary
var actualIndices = new Dictionary <IElement, IndexPair>();
foreach (var element in grid.Children)
{
if (element.ColumnSpan < 1 || element.RowSpan < 1)
{
throw new ArgumentOutOfRangeException("grid", "UI elements must not have negative column or row spans.");
}
actualIndices.Add(element, new IndexPair
{
ColumnIndex = Math.Min(element.ColumnIndex, columns.Count - 1),
RowIndex = Math.Min(element.RowIndex, rows.Count - 1)
});
}
#endregion
#region Find indices of auto controls
if (actualIndices.Keys.Any(control => control.RowIndex < 0 || control.ColumnIndex < 0))
{
var columnHeights = new int[columns.Count];
//Copy controls to an array in case the controls collection is modified
var controls = new IElement[actualIndices.Count];
actualIndices.Keys.CopyTo(controls, 0);
foreach (var control in controls)
{
var controlIndex = actualIndices[control];
var autoControl = controlIndex.RowIndex == Element.AutoLayoutIndex || controlIndex.ColumnIndex == Element.AutoLayoutIndex;
if (controlIndex.RowIndex == Element.AutoLayoutIndex)
{
// If we have a column index, honor it
if (controlIndex.ColumnIndex >= 0)
{
controlIndex.RowIndex = columnHeights.Skip(controlIndex.ColumnIndex).Take(control.ColumnSpan).Max();
var obstructors = GetGridControls(actualIndices, controlIndex.RowIndex, controlIndex.ColumnIndex, control).ToList();
while (obstructors.Any())
{
// Try the next available row
controlIndex.RowIndex = obstructors.Max(p => p.Value.RowIndex + p.Key.RowSpan);
obstructors = GetGridControls(actualIndices, controlIndex.RowIndex, controlIndex.ColumnIndex, control).ToList();
}
}
else
{
// Set a minimum row and drop to auto-column logic
controlIndex.RowIndex = columnHeights.Min();
}
}
// Place in specified row or one with an available span of columns
while (controlIndex.ColumnIndex == Element.AutoLayoutIndex)
{
controlIndex.ColumnIndex = GetColumnForRow(controlIndex.RowIndex, columns.Count, control, actualIndices);
if (controlIndex.ColumnIndex > Element.AutoLayoutIndex)
{
break;
}
var candidates = columnHeights.Where(r => r > controlIndex.RowIndex).ToList();
controlIndex.RowIndex = candidates.Any() ? candidates.Min() : rows.Count;
}
while (control.RowSpan + controlIndex.RowIndex > rows.Count)
{
rows.Add(Row.AutoSized);
}
actualIndices[control] = controlIndex;
// Record high water mark for each column the control occludes.
for (int i = 0; i < control.ColumnSpan && controlIndex.ColumnIndex + i < columnHeights.Length; i++)
{
int nextAvailableRow = controlIndex.RowIndex + control.RowSpan;
// Auto controls always leave a high water mark. Manually-placed controls only occlude
// completely filled columns so that auto controls may be placed above them.
if (autoControl || controlIndex.RowIndex == columnHeights[controlIndex.ColumnIndex + i])
{
//If a manual control blocks the next row, include it in the high water mark.
Dictionary <IElement, IndexPair> idxs;
while ((idxs = actualIndices.Where(v =>
v.Value.ColumnIndex <= controlIndex.ColumnIndex + i &&
v.Value.ColumnIndex + v.Key.ColumnSpan > controlIndex.ColumnIndex + i &&
v.Value.RowIndex <= nextAvailableRow &&
v.Value.RowIndex + v.Key.RowSpan > nextAvailableRow)
.ToDictionary(p => p.Key, p => p.Value)).Any())
{
nextAvailableRow = idxs.Max(p => p.Value.RowIndex + p.Key.RowSpan);
}
columnHeights[controlIndex.ColumnIndex + i] = nextAvailableRow;
}
}
}
}
#endregion
var scale = iApp.Factory.GetDisplayScale();
maximumSize.Height *= scale;
minimumSize.Height *= scale;
// total grid size minus grid padding
double totalGridWidth = double.IsInfinity(maximumSize.Width) ? double.MaxValue : maximumSize.Width;
double totalGridHeight = double.IsInfinity(maximumSize.Height) ? double.MaxValue : maximumSize.Height;
totalGridWidth -= (grid.Padding.Left + grid.Padding.Right) * scale;
totalGridHeight -= (grid.Padding.Top + grid.Padding.Bottom) * scale;
// available grid size for autos
double availableGridWidth = totalGridWidth;
double availableGridHeight = totalGridHeight;
var rowSpaces = new Space[rows.Count];
var columnSpaces = new Space[columns.Count];
var elementSizes = new Dictionary <IElement, Size>(actualIndices.Count);
#region Star sizing with no size limit
// if there are any star rows or columns and the maximum size is infinite,
// treat the star with the smallest weight as an auto and use it to size the others.
int baseStarRowIndex = -1;
if (double.IsInfinity(maximumSize.Height))
{
double minWeight = double.MaxValue;
for (int i = 0; i < rows.Count; i++)
{
var row = rows[i];
if (row.UnitType == LayoutUnitType.Star && minWeight > row.Height)
{
minWeight = row.Height;
baseStarRowIndex = i;
}
}
if (baseStarRowIndex >= 0)
{
rows[baseStarRowIndex] = new Row(rows[baseStarRowIndex].Height, LayoutUnitType.Auto);
}
}
int baseStarColumnIndex = -1;
if (double.IsInfinity(maximumSize.Width))
{
double minWeight = double.MaxValue;
for (int i = 0; i < columns.Count; i++)
{
var column = columns[i];
if (column.UnitType == LayoutUnitType.Star && minWeight > column.Width)
{
minWeight = column.Width;
baseStarColumnIndex = i;
}
}
if (baseStarColumnIndex >= 0)
{
columns[baseStarColumnIndex] = new Column(columns[baseStarColumnIndex].Width, LayoutUnitType.Auto);
}
}
#endregion
#region Absolute sizing
for (int rIndex = 0; rIndex < rows.Count; rIndex++)
{
Row row = rows[rIndex];
if (row.UnitType == LayoutUnitType.Absolute)
{
availableGridHeight -= row.Height * scale;
rowSpaces[rIndex].Size = row.Height * scale;
}
}
for (int cIndex = 0; cIndex < columns.Count; cIndex++)
{
Column column = columns[cIndex];
if (column.UnitType == LayoutUnitType.Absolute)
{
availableGridWidth -= column.Width * scale;
columnSpaces[cIndex].Size = column.Width * scale;
}
}
#endregion
// loop through every child element, regardless of column/row indices or spans, and determine its desired size.
// this is considered the 'measure' pass and is just to get an idea of how much space each element wants.
foreach (var kvp in actualIndices)
{
var element = kvp.Key;
var indexPair = kvp.Value;
if (element.Visibility == Visibility.Collapsed)
{
elementSizes[element] = Size.Empty;
continue;
}
double maxElementWidth = 0;
double maxElementHeight = 0;
bool inAutoColumn = false, inAutoRow = false, takeAll = false;
int lastColumn = Math.Min(columns.Count, indexPair.ColumnIndex + element.ColumnSpan);
for (int i = indexPair.ColumnIndex; i < lastColumn; i++)
{
var column = columns[i];
if (column.UnitType == LayoutUnitType.Absolute)
{
maxElementWidth += column.Width;
}
else if (!takeAll)
{
// if the element spans any auto or star column, its constraining width will include the
// entire available grid width minus any absolutes that the element is not a part of.
// this is because we don't know the final size of these columns yet, and we need to assume
// that they will take all of the grid's remaining available space.
takeAll = true;
maxElementWidth += availableGridWidth;
}
if (column.UnitType == LayoutUnitType.Auto)
{
inAutoColumn = true;
}
}
takeAll = false;
int lastRow = Math.Min(rows.Count, indexPair.RowIndex + element.RowSpan);
for (int i = indexPair.RowIndex; i < lastRow; i++)
{
var row = rows[i];
if (row.UnitType == LayoutUnitType.Absolute)
{
maxElementHeight += row.Height;
}
else if (!takeAll)
{
// if the element spans any auto row, its constraining height will include the
// entire available grid height minus any absolutes that the element is not a part of.
// this is because we don't know the final size of these rows yet, and we need to assume
// that they will take all of the grid's remaining available space.
takeAll = true;
maxElementHeight += availableGridHeight;
}
if (row.UnitType == LayoutUnitType.Auto)
{
inAutoRow = true;
}
}
// if the element doesn't span any autos, we don't need to measure it in this pass
if (!inAutoColumn && !inAutoRow)
{
continue;
}
var desiredSize = element.Measure(new Size(Math.Max(0, maxElementWidth - (element.Margin.Left + element.Margin.Right) * scale),
Math.Max(0, maxElementHeight - (element.Margin.Top + element.Margin.Bottom) * scale)));
elementSizes[element] = desiredSize;
// if the element only spans one auto column, we can use it to determine the ultimate width for the column
if (indexPair.ColumnIndex == (lastColumn - 1) && columns[indexPair.ColumnIndex].UnitType == LayoutUnitType.Auto)
{
double totalWidth = Math.Max(desiredSize.Width + (element.Margin.Left + element.Margin.Right) * scale, 0);
var space = columnSpaces[indexPair.ColumnIndex];
if (space.Size < totalWidth)
{
space.Size = totalWidth;
columnSpaces[indexPair.ColumnIndex] = space;
}
}
// if the element only spans one auto row, we can use it to determine the ultimate height for the row
if (indexPair.RowIndex == (lastRow - 1) && rows[indexPair.RowIndex].UnitType == LayoutUnitType.Auto)
{
double totalHeight = Math.Max(desiredSize.Height + (element.Margin.Top + element.Margin.Bottom) * scale, 0);
var space = rowSpaces[indexPair.RowIndex];
if (space.Size < totalHeight)
{
space.Size = totalHeight;
rowSpaces[indexPair.RowIndex] = space;
}
}
}
SizeColumns(grid, minimumSize.Width, availableGridWidth, columns, columnSpaces, baseStarColumnIndex, scale);
SizeRows(grid, minimumSize.Height, availableGridHeight, rows, rowSpaces, baseStarRowIndex, scale);
// this is considered the 'arrange' pass and is where we get the final size of each element before giving them an XY position.
// at this point, all columns and rows should have a size that's pretty close to their final size.
// some adjustments may be required if the second measurement of an element causes an auto row or column to be resized.
foreach (var keyValue in actualIndices)
{
var element = keyValue.Key;
var indexPair = keyValue.Value;
if (element.Visibility == Visibility.Collapsed)
{
element.SetLocation(new Point(columnSpaces[indexPair.ColumnIndex].Origin, rowSpaces[indexPair.RowIndex].Origin), Size.Empty);
continue;
}
var marginLeft = element.Margin.Left * scale;
var marginTop = element.Margin.Top * scale;
var marginRight = element.Margin.Right * scale;
var marginBottom = element.Margin.Bottom * scale;
Space rowSpace = rowSpaces[indexPair.RowIndex];
for (int i = indexPair.RowIndex + 1; i < (indexPair.RowIndex + element.RowSpan) && i < rows.Count; i++)
{
rowSpace.Size += rowSpaces[i].Size;
}
Space columnSpace = columnSpaces[indexPair.ColumnIndex];
for (int i = indexPair.ColumnIndex + 1; i < (indexPair.ColumnIndex + element.ColumnSpan) && i < columns.Count; i++)
{
columnSpace.Size += columnSpaces[i].Size;
}
var constraints = new Size(columnSpace.Size - (marginLeft + marginRight), rowSpace.Size - (marginTop + marginBottom));
// labels are a bit special; as one dimension expands or contracts, the other dimension inversely contracts or expands.
// because of this, if the column width is shorter than the label's desired width, the label will likely want more
// vertical space than its desired height suggests. to compensate for this, if the label spans any auto row,
// we reset the vertical constraint before the label's final measurement and adjust any rows as needed.
if (element is ILabel)
{
int lastRow = Math.Min(rows.Count, indexPair.RowIndex + element.RowSpan);
for (int i = indexPair.RowIndex; i < lastRow; i++)
{
if (rows[i].UnitType == LayoutUnitType.Auto)
{
constraints.Height = double.MaxValue;
break;
}
}
}
constraints.Width = Math.Max(constraints.Width, 0);
constraints.Height = Math.Max(constraints.Height, 0);
var finalSize = element.Measure(constraints);
var totalFinalSize = new Size(finalSize.Width + (marginLeft + marginRight), finalSize.Height + (marginTop + marginBottom));
var desiredSize = elementSizes.GetValueOrDefault(element);
var totalDesiredSize = new Size(desiredSize.Width + (marginLeft + marginRight), desiredSize.Height + (marginTop + marginBottom));
// if the final size is different from the desired size, see if any row or column needs adjustment.
if (Math.Abs(totalFinalSize.Width - totalDesiredSize.Width) > 0.01)
{
int trueColumnSpan = Math.Min(columns.Count - indexPair.ColumnIndex, element.ColumnSpan);
if (trueColumnSpan == 1 && columns[indexPair.ColumnIndex].UnitType == LayoutUnitType.Auto)
{
// if the final width is larger than the current size of the column, we need to expand the column.
// on the other hand, if this element is what determined the column's initial size and its final
// width is smaller, we need to shrink the column.
if (totalFinalSize.Width > columnSpace.Size || (totalDesiredSize.Width == columnSpace.Size &&
!elementSizes.Any(e => e.Key != element && actualIndices[e.Key].ColumnIndex == indexPair.ColumnIndex &&
e.Value.Width + (marginLeft + marginRight) >= columnSpace.Size)))
{
columnSpace.Size = totalFinalSize.Width;
columnSpaces[indexPair.ColumnIndex] = columnSpace;
SizeColumns(grid, minimumSize.Width, availableGridWidth, columns, columnSpaces, baseStarColumnIndex, scale);
// SizeColumns may have shrunk the column if it was too large to fit in the grid
totalFinalSize.Width = columnSpaces[indexPair.ColumnIndex].Size;
}
}
}
if (Math.Abs(totalFinalSize.Height - totalDesiredSize.Height) > 0.01)
{
int trueRowSpan = Math.Min(rows.Count - indexPair.RowIndex, element.RowSpan);
if (trueRowSpan == 1 && rows[indexPair.RowIndex].UnitType == LayoutUnitType.Auto)
{
// if the final height is larger than the current size of the row, we need to expand the row.
// on the other hand, if this element is what determined the row's initial size and its final
// height is smaller, we need to shrink the row.
if (totalFinalSize.Height > rowSpace.Size || (totalDesiredSize.Height == rowSpace.Size &&
!elementSizes.Any(e => e.Key != element && actualIndices[e.Key].RowIndex == indexPair.RowIndex &&
e.Value.Height + (marginTop + marginBottom) >= rowSpace.Size)))
{
rowSpace.Size = totalFinalSize.Height;
rowSpaces[indexPair.RowIndex] = rowSpace;
SizeRows(grid, minimumSize.Height, availableGridHeight, rows, rowSpaces, baseStarRowIndex, scale);
// SizeRows may have shrunk the row if it was too large to fit in the grid
totalFinalSize.Height = rowSpaces[indexPair.RowIndex].Size;
}
}
}
finalSize = new Size(totalFinalSize.Width - (marginLeft + marginRight), totalFinalSize.Height - (marginTop + marginBottom));
var availableArea = new Size(columnSpace.Size - (marginLeft + marginRight), rowSpace.Size - (marginTop + marginBottom));
var image = element as IImage;
if (image == null)
{
var button = element as IButton;
if (button != null)
{
image = button.Image;
}
}
if (image != null)
{
var dimensions = image.Dimensions;
var ratio = dimensions.Width / dimensions.Height;
switch (image.Stretch)
{
case ContentStretch.Fill:
case ContentStretch.UniformToFill:
// in the case of UniformToFill, it is the platform's responsibility to clip the image
finalSize.Width = availableArea.Width;
finalSize.Height = availableArea.Height;
break;
case ContentStretch.None:
// Stretch.None should still shrink the image if it's too large to fit in its space
if (finalSize.Width < dimensions.Width || finalSize.Height < dimensions.Height)
{
if (finalSize.Width > finalSize.Height * ratio)
{
finalSize.Width = finalSize.Height * ratio;
}
else if (finalSize.Width < finalSize.Height * ratio)
{
finalSize.Height = finalSize.Width / ratio;
}
}
break;
case ContentStretch.Uniform:
if (availableArea.Width > availableArea.Height * ratio)
{
finalSize.Width = availableArea.Height * ratio;
finalSize.Height = availableArea.Height;
}
else if (availableArea.Width < availableArea.Height * ratio)
{
finalSize.Width = availableArea.Width;
finalSize.Height = availableArea.Width / ratio;
}
break;
}
}
var location = new Point(columnSpace.Origin, rowSpace.Origin);
switch (element.VerticalAlignment)
{
case VerticalAlignment.Stretch:
location.Y = rowSpace.Origin + marginTop;
finalSize.Height = availableArea.Height;
break;
case VerticalAlignment.Top:
location.Y = rowSpace.Origin + marginTop;
finalSize.Height = Math.Min(finalSize.Height, availableArea.Height);
break;
case VerticalAlignment.Bottom:
location.Y = (rowSpace.Origin + rowSpace.Size) - (finalSize.Height + marginBottom);
finalSize.Height = Math.Min(finalSize.Height, availableArea.Height);
break;
case VerticalAlignment.Center:
location.Y = (availableArea.Height / 2f) - (finalSize.Height / 2f) + (rowSpace.Origin + marginTop);
finalSize.Height = Math.Min(finalSize.Height, availableArea.Height);
break;
}
switch (element.HorizontalAlignment)
{
case HorizontalAlignment.Stretch:
location.X = columnSpace.Origin + marginLeft;
finalSize.Width = availableArea.Width;
break;
case HorizontalAlignment.Left:
location.X = columnSpace.Origin + marginLeft;
finalSize.Width = Math.Min(finalSize.Width, availableArea.Width);
break;
case HorizontalAlignment.Right:
location.X = (columnSpace.Origin + columnSpace.Size) - (finalSize.Width + marginRight);
finalSize.Width = Math.Min(finalSize.Width, availableArea.Width);
break;
case HorizontalAlignment.Center:
location.X = (availableArea.Width / 2f) - (finalSize.Width / 2f) + (columnSpace.Origin + marginLeft);
finalSize.Width = Math.Min(finalSize.Width, columnSpace.Size - marginLeft - marginRight);
break;
}
finalSize.Width = Math.Max(finalSize.Width, 0);
finalSize.Height = Math.Max(finalSize.Height, 0);
elementSizes[element] = finalSize;
element.SetLocation(location, finalSize);
}
// everything is laid out to the maximum size, so we know that we haven't exceeded it
return(new Size(Math.Max(columnSpaces.Sum(c => c.Size) + scale * (grid.Padding.Left + grid.Padding.Right), minimumSize.Width),
Math.Max(rowSpaces.Sum(r => r.Size) + (grid.Padding.Top + grid.Padding.Bottom) * scale, minimumSize.Height)));
}