$11.$ Answer these questions about or modify our class code$($look on Blackboard.

a$.$ Which statement does a toggle?

b$.$ Write code that changes the timer start button text Stop timer. Then when pressed again the button stops the Timer and changes the text back to Start Timer. So the timer button toggles on and off.

c$.$ Add the checkers to the board as below:

To place an image use this syntax:

Graphics.DrawImage$($RedChecker$,$ x$,$y$,$width,height$)$

$-$ Use BlackChecker for the black checkers.

Make annotations in the code.

$$

$\{$public partial class Form$1$ : Form

$\{$

int numseconds $=10$;

public Form$1()$

$\{$

InitializeComponent$()$;

$\}$

private void Form$1\_$Paint$($object sender$,$ PaintEventArgs e$)$

$\{$

Random r $=$ new Random$(15)$;

Graphics ourgraphics;

ourgraphics $=$ e$.$Graphics;

SolidBrush backbrush $=$ new SolidBrush$($Color$.$Silver$)$;

ourgraphics.FillRectangle$($backbrush$,200,350,410,410)$;

SolidBrush boardbrush $=$ new SolidBrush$($Color$.$Red$)$;

int xcoord,ycoord;

Boolean redflag $=$ false;

int squaresize $=48$;

for $($int j $=1$; j ;j$++)\{$

xcoord $=200$;

for $($int i $=1$; i ; i$++)$

$\{$

ycoord $=$ j $*($squaresize$+4)+300$;

if $($redflag$)$

$\{$

boardbrush $=$ new SolidBrush$($Color$.$Red$)$;

$\}$ else

$\{$

boardbrush $=$ new SolidBrush$($Color$.$Black$)$;

$\}$

ourgraphics.FillRectangle$($boardbrush$,$ xcoord, ycoord, squaresize, squaresize$)$;

xcoord $=$ xcoord $+$ squaresize$+4$;

redflag $=!$redflag;

$\}$

redflag $=!$redflag;

$\}$

$//$ factor$1=10\%,$ factor$2=20\%$ factor$2=30\%,$ factor$4=40\%$

int$[]$ percentages$=\{10,20,30,40\}$;

Color$[]$ colors $=\{$ Color.Orange,Color.Bisque, Color.Navy, Color.Aquamarine $\}$;

$//$ rewrite the code to generate the pie chart

int startangle $=0$;

int alpha $=100$;

for $($int j $=0$; j $<mtext\; id="EditorElement\_17740340"></mtext><mn\; id="EditorElement\_17740341">1</mn><mn\; id="EditorElement\_17740342">0</mn>$; j$++)$

$\{$

startangle $+=1$;

SolidBrush piebrush;

int current$\_$angle $=$ startangle;

for $($int i $=0$; i $$ percentages.Length; i$++)$

$\{$

$//$piebrush $=$ new SolidBrush$($colors$[$i$])$;

$//$int red $=$ piebrush.Color.R $+1$;

$//$int green $=$ piebrush.Color.G $+1$;

$//$int blue $=$ piebrush.Color.B$+1$;

$//$if $($red $>255)\{$ red $=255$; $\}$

$//$if $($green $>255)\{$ green $=255$; $\}$

$//$if $($blue $>255)\{$ blue $=255$; $\}$

$//$if $($alpha$<mn\; id="EditorElement\_17740946">0</mn><mi\; id="EditorElement\_17740947">)</mi><mtext\; id="EditorElement\_17740948"></mtext><mi\; id="EditorElement\_17740949">\{</mi>$ alpha $=0$; $\}$

int red $=$ r$.$Next$(0,255)$;

int green $=$ r$.$Next$(0,255)$;

int blue $=$ r$.$Next$(0,255)$;

piebrush $=$ new SolidBrush$($Color$.$FromArgb$($alpha$,$red, green, blue$))$;

colors$[$i$]=$ piebrush.Color;

double sweepangle $=360*(($double$)$percentages$[$i$]/100)$;

ourgraphics.FillPie$($piebrush$,300,10,200,200,$ current$\_$angle, $($int$)$sweepangle$)$;

current$\_$angle $+=($int$)$sweepangle;

$\}$

Thread.Sleep$(3000)$;

$\}$

$//$SolidBrush factor$1=$ new SolidBrush$($Color$.$Orange$)$;

$//$SolidBrush factor$2=$ new SolidBrush$($Color$.$Bisque$)$;

$//$SolidBrush factor$3=$ new SolidBrush$($Color$.$Navy$)$;

$//$SolidBrush factor$4=$ new SolidBrush$($Color$.$Aquamarine$)$;

$//$ourgraphics$.$FillPie$($factor$1,300,10,200,200,0,36)$;

$//$ourgraphics$.$FillPie$($factor$2,300,10,200,200,36,72)$;

$//$ourgraphics$.$FillPie$($factor$3,300,10,200,200,108,108)$;

$//$ourgraphics$.$FillPie$($factor$4,300,10,200,200,216,144)$;

$\}$

private void timer$1\_$Tick$($object sender$,$ EventArgs e$)$

$\{$

numseconds $=$ numseconds $-1$;

button$1.$Text $=$ numseconds.ToString$()$;

$\}$

private void Form$1\_$Load$($object sender$,$ EventArgs e$)$

$\{$

$\}$

private void button$1\_$Click$($object sender$,$ EventArgs e$)$

$\{$

timer$1.$Start$()$;

$\}$

$\}$