/**********************************************************************
*********************************************************************/
void B_Restart_Clicked(object sender, EventArgs e)
{
SequenceList = new List <int>(OrigSequenceList);
ram = new int[SequenceList.Count, ramSize, 6];
disc = new int[SequenceList.Count, discSize];
currentStep = -1; //no page in ram or disc yet
currentPage = -1;
indexCurrentPage = -1;
sequenceLength = SequenceList.Count();
pagesInRam = new List <int>();
pagesInDisc = new List <int>();
draw = new PageReplacementStrategiesDraw(ramSize, discSize, sequenceLength, SequenceList);
CreateContent();
//enable/disable buttons
b_Set_Mbit.IsEnabled = false;
b_Reset_Rbits.IsEnabled = false;
b_Set_Rbit.IsEnabled = false;
b_Next.IsEnabled = true;
b_Restart.IsEnabled = false;
InitializeDisc(disc);
InitializeRam(ram);
}
/**********************************************************************
*********************************************************************/
void CreateTopHalf(Grid grid)
{
skiaview = new SKCanvasView();
skiaview = PageReplacementStrategiesDraw.ReturnCanvas();
skiaview.BackgroundColor = App._viewBackground;
grid.Children.Add(skiaview, 0, 0);
}
/**********************************************************************
*********************************************************************/
void B_Set_Mbit_Clicked(object sender, EventArgs e)
{
if (currentStep > -1)
{
//set m-bit of current page
ram[currentStep, indexCurrentPage, 2] = 1;
ram[currentStep, 0, 5] = 1;
}
PageReplacementStrategiesDraw.Paint();//Update Canvas
}
//METHODS
/**********************************************************************
*********************************************************************/
void B_Set_Rbit_Clicked(object sender, EventArgs e)
{
if (currentStep > -1)
{
//Set r-bit of current page
ram[currentStep, indexCurrentPage, 1] = 1;
//ram[currentStep, 0, 4] = 1;
PageReplacementStrategiesDraw.Paint();//Update Canvas
}
}
//CONSTRUCTOR
public PageReplacementStrategies(List <int> l, String s, int r, int d)
{
ToolbarItem info = new ToolbarItem();
info.Text = App._sHelpInfoHint;
this.ToolbarItems.Add(info);
info.Clicked += B_Info_Clicked;
OrigSequenceList = new List <int>(l);
SequenceList = l;
strategy = s;
ramSize = r;
discSize = d;
//Ram array explanation
//[step, ram , 0] = pagenumber (range 0-9, -1 -> no page)
//[step, ram , 1] = r-bit (0 -> not set, 1 -> set)
//[step, ram , 2] = m-bit (0 -> not set, 1 -> set)
//[step, ram , 3] = pagefail (0 -> no pagefail, 1 -> pagefail without replacement, 2 -> pagefail with replacement)
//[step, ram , 4] = r bits were reset in this step -> 1, else -> 0
//[step, ram , 5] = m bit was set in this step -> 1, else -> 0
ram = new int[SequenceList.Count, ramSize, 6];
disc = new int[SequenceList.Count, discSize];
currentStep = -1; //no page in ram or disc yet
currentPage = -1;
indexCurrentPage = -1;
sequenceLength = SequenceList.Count();
pagesInRam = new List <int>();
pagesInDisc = new List <int>();
draw = new PageReplacementStrategiesDraw(ramSize, discSize, sequenceLength, SequenceList);
Title = "Page Replacement Strategies: " + strategy; //since the name is longer than average,
//the button ahead will automatically be named "back" instead of "Betriebssysteme"
CreateContent();
//enable/disable buttons
b_Set_Mbit.IsEnabled = false;
b_Reset_Rbits.IsEnabled = false;
b_Set_Rbit.IsEnabled = false;
b_Next.IsEnabled = true;
// content starts only after notch
On <iOS>().SetUseSafeArea(true);
InitializeDisc(disc);
InitializeRam(ram);
}
/**********************************************************************
*********************************************************************/
void B_Reset_Rbits_Clicked(object sender, EventArgs e)
{
if (currentStep > -1)
{
//reset all r-bits of current step in ram
for (int j = 0; j <= ram.GetUpperBound(1); j++)
{
if (ram[currentStep, j, 1] == 1)
{
ram[currentStep, j, 1] = 0; //r-bit reset
ram[currentStep, j, 4] = 1; //mark r-bit as reset
}
}
PageReplacementStrategiesDraw.Paint();//Update Canvas
}
}
/**********************************************************************
*********************************************************************/
void B_Next_Clicked(object sender, EventArgs e)
{
currentStep++;
currentPage = SequenceList.First();
SequenceList.Remove(SequenceList.First());
switch (strategy)
{
case "Optimal Strategy":
Optimal();
break;
case "FIFO":
Fifo();
break;
case "FIFO Second Chance":
FifoSecond();
break;
case "RNU FIFO":
Rnu();
b_Reset_Rbits.IsEnabled = true;
b_Set_Rbit.IsEnabled = true;
b_Set_Mbit.IsEnabled = true;
break;
case "RNU FIFO Second Chance":
RnuSecond();
b_Reset_Rbits.IsEnabled = true;
b_Set_Rbit.IsEnabled = true;
b_Set_Mbit.IsEnabled = true;
break;
}
PageReplacementStrategiesDraw.Paint();//Update Canvas
b_Restart.IsEnabled = true;
//disable next button if the sequence was processed entirely
if (currentStep == sequenceLength - 1)
{
b_Next.IsEnabled = false;
}
}