/// <summary>
/// Remove top view on stack
/// </summary>
/// <param name="animated">Flags for animation</param>
public async Task Pop(bool animated)
{
if (Top != null)
{
var tobeRemoved = Top;
if (animated)
{
if (PopAnimation != null)
{
await RunCustomPopAnimation(tobeRemoved, PopAnimation);
}
else
{
await RunDefaultPopAnimation(tobeRemoved);
}
}
InternalStack.Remove(tobeRemoved);
_focusStack.Remove(tobeRemoved);
Remove(tobeRemoved);
UpdateTopView();
tobeRemoved.Dispose();
}
}
/// <summary>
/// Inserts a view in the navigation stack before an existing view in the stack.
/// </summary>
/// <param name="before">The existing view, before which view will be inserted.</param>
/// <param name="view">The view to insert</param>
public void Insert(View before, View view)
{
view.Hide();
var idx = InternalStack.IndexOf(before);
InternalStack.Insert(idx, view);
Add(view);
UpdateTopView();
}
public void Insert(EvasObject before, EvasObject view)
{
view.Hide();
var idx = InternalStack.IndexOf(before);
InternalStack.Insert(idx, view);
PackEnd(view);
UpdateTopView();
}
public void Remove(EvasObject view)
{
InternalStack.Remove(view);
UnPack(view);
UpdateTopView();
Device.BeginInvokeOnMainThread(() =>
{
view?.Unrealize();
});
}
private void OnResizeRequested(InternalStack stack)
{
if (First.Count + Second.Count + Third.Count == _array.Length)
{
throw new InvalidOperationException("No more room");
}
if (stack == _first)
{
if (_second.IsFull)
{
_third.MoveForward();
_third.DecrementMaxCount();
_second.MoveForward();
}
else
{
_second.MoveForward();
_second.DecrementMaxCount();
}
_first.IncrementMaxCount();
}
else if (stack == _second)
{
if (_third.IsFull)
{
_first.DecrementMaxCount();
_second.MoveBackward();
}
else
{
_third.MoveForward();
_third.DecrementMaxCount();
}
_second.IncrementMaxCount();
}
else if (stack == _third)
{
if (_second.IsFull)
{
_first.DecrementMaxCount();
_second.MoveBackward();
}
else
{
_second.DecrementMaxCount();
}
_third.MoveBackward();
_third.IncrementMaxCount();
}
}
/// <summary>
/// Clear all children
/// </summary>
public void Clear()
{
foreach (var child in InternalStack)
{
Remove(child);
child.Dispose();
}
InternalStack.Clear();
_focusStack.Clear();
_lastTop = null;
}
void UpdateTopView()
{
if (CurrentView != InternalStack.LastOrDefault())
{
if (!IsPreviousViewVisible)
{
CurrentView?.Hide();
}
CurrentView = InternalStack.LastOrDefault();
CurrentView?.Show();
(CurrentView as Widget)?.SetFocus(true);
}
}
public void Pop()
{
if (CurrentView != null)
{
var tobeRemoved = CurrentView;
InternalStack.Remove(tobeRemoved);
UnPack(tobeRemoved);
UpdateTopView();
// if Pop was called by removed page,
// Unrealize cause deletation of NativeCallback, it could be a cause of crash
Device.BeginInvokeOnMainThread(() =>
{
tobeRemoved.Unrealize();
});
}
}
public ThreeSlidingStacks(int maxTotalCount)
{
_array = new int[maxTotalCount];
var firstStart = 0;
var firstCount = maxTotalCount / 3;
var secondStart = firstCount + 1;
var secondCount = maxTotalCount / 3;
var thirdStart = secondCount + 1;
var thirdCount = maxTotalCount - secondCount - firstCount;
_first = new InternalStack(firstStart, firstCount, _array, OnResizeRequested);
_second = new InternalStack(secondStart, secondCount, _array, OnResizeRequested);
_third = new InternalStack(thirdStart, thirdCount, _array, OnResizeRequested);
}
public ThreeStacks(int maxTotalCount)
{
var array = new int[maxTotalCount];
var firstStart = 0;
var firstCount = maxTotalCount / 3;
var secondStart = firstCount + 1;
var secondCount = maxTotalCount / 3;
var thirdStart = secondCount + 1;
var thirdCount = maxTotalCount - secondCount - firstCount;
First = new InternalStack(firstStart, firstCount, array);
Second = new InternalStack(secondStart, secondCount, array);
Third = new InternalStack(thirdStart, thirdCount, array);
}
public void Push(EvasObject view, bool isAnimated = false)
{
InternalStack.Add(view);
PackEnd(view);
if (isAnimated)
{
if (CurrentView != null)
{
CurrentView.AllEventsFrozen = true;
}
}
else
{
UpdateTopView();
}
}
public float CalculateONPExpresion(string onpExpression)
{
int id = 0;
OutputOperationBuffer = new InternalBuffer<OutputOperation>();
InternalStack<string> stack = new InternalStack<string>();
List<string> tokenList = onpExpression.Trim().Split(' ').ToList();
string input = onpExpression.Trim();
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), string.Empty));
foreach (string token in tokenList)
{
if (!string.IsNullOrEmpty(input.Trim()))
input = input.Trim().Remove(0, 1);
if (token.IsOperator())
{
string secondToken = stack.Pop();
string firstToken = stack.Pop();
string result = Calculate(token, firstToken, secondToken);
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), string.Format("{0} {1} {2}", firstToken, token, secondToken)));
stack.Push(result);
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), string.Empty));
}
else
{
stack.Push(token);
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), string.Empty));
}
}
string resultToken = stack.Pop();
float resultValue = float.Parse(resultToken);
return resultValue;
}
/// <summary>
/// Push a view on stack
/// </summary>
/// <param name="view">A view to push</param>
/// <param name="animated">Flags for animation</param>
public async Task Push(View view, bool animated)
{
DidSaveFocus();
view.WidthResizePolicy = ResizePolicyType.FillToParent;
view.HeightResizePolicy = ResizePolicyType.FillToParent;
InternalStack.Add(view);
Add(view);
if (animated)
{
if (PushAnimation != null)
{
await RunCustomPushAnimation(view, PushAnimation);
}
else
{
await RunDefaultPushAnimation(view);
}
}
UpdateTopView();
}
void UpdateTopView()
{
if (_lastTop != InternalStack.LastOrDefault())
{
if (_lastTop != null)
{
if (!ShownBehindPage)
{
_lastTop.Hide();
}
_lastTop.FocusableChildren = false;
}
_lastTop = InternalStack.LastOrDefault();
if (_lastTop != null)
{
_lastTop.Show();
_lastTop.FocusableChildren = true;
}
SendNavigated();
DidRestoreFocus();
}
}
/// <summary>
/// Removes a view in the navigation stack
/// </summary>
/// <param name="view">The view to remove</param>
public void Pop(View view)
{
InternalStack.Remove(view);
_focusStack.Remove(view);
Remove(view);
}
public string ConvertToONP(string infix)
{
int id = 0;
OutputOperationBuffer = new InternalBuffer<OutputOperation>();
InternalStack<Operator> stack = new InternalStack<Operator>();
string output = string.Empty;
char[] infixArray = infix.Trim().ToArray();
string input = infix;
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), output));
foreach (char infixChar in infixArray)
{
if(!string.IsNullOrEmpty(input))
input = input.Remove(0, 1);
if (!infixChar.IsOperator())
{
AddToOutput(ref output, infixChar);
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), output));
}
else if (infixChar == Operators.OpenBracket)
{
AddToOutput(ref output);
Operator newOperator = new Operator(infixChar);
stack.Push(newOperator);
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), output));
}
else if (infixChar == Operators.CloseBracket)
{
AddToOutput(ref output);
Operator newOperator = new Operator(infixChar);
while (stack.Any() && stack.Peek().OperatorType != Operators.OpenBracket)
{
AddToOutput(ref output, stack.Pop());
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), output));
}
stack.Pop();
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), output));
}
else
{
AddToOutput(ref output);
Operator newOperator = new Operator(infixChar);
while (stack.Any() && stack.Peek().Priority >= newOperator.Priority)
{
AddToOutput(ref output, stack.Pop());
}
stack.Push(newOperator);
OutputOperationBuffer.Push(new OutputOperation(id++, input, stack.ToReverseString(), output));
}
}
while (stack.Any())
{
AddToOutput(ref output, stack.Pop());
}
return output;
}
