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Winform PictureBox dynamic update

In my winform control I am adding picture box and assigning an image from the Resources. This works great, however I need to change the image based on business logic and this is where the issue begins. I am setting up the Image to the new one but it refuses to get updated. I have also tried to use Refresh, Update or Invalidate on a picturebox again without any success. How to change the picturebox image dynamically ? Am I using the right control?
Below is Designer autogenerated code which works fine:
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.pictureBox1 = new System.Windows.Forms.PictureBox();
((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
this.SuspendLayout();
//
// pictureBox1
//
this.pictureBox1.Dock = System.Windows.Forms.DockStyle.Fill;
this.pictureBox1.Image = global::UnumIDOutlookAddIn.Properties.Resources.MyImage;
this.pictureBox1.Location = new System.Drawing.Point(0, 0);
this.pictureBox1.Name = "pictureBox1";
this.pictureBox1.Size = new System.Drawing.Size(616, 86);
this.pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.Zoom;
this.pictureBox1.TabIndex = 1;
this.pictureBox1.TabStop = false;
//
// WinformComponent
//
this.AutoScaleDimensions = new System.Drawing.SizeF(9F, 20F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.Controls.Add(this.pictureBox1);
this.Name = "WinformComponent";
this.Size = new System.Drawing.Size(616, 86);
(this.pictureBox1)).EndInit();
this.ResumeLayout(false);
}
However, later on I am trying to update the Image, and it never updates. I have tried to differnt order on the last three lines without any success as well.
mycomponent.pictureBox1.Image = Resources.AnotherImage;
mycomponent.pictureBox1.Invalidate(); <-- Tried many configuratons
mycomponent.pictureBox1.Update();
mycomponent.pictureBox1.Refresh();

** I'm completely guessing as to what your problem is. **
Most likely you're doing something like this:
Form1 mycomponent = new Form1(); // Form1 is just an example
mycomponent.pictureBox1.Image = Resources.AnotherImage;
You're making a NEW form and updating the pictureBox on that Form, a Form that is never actually displayed.
If you want to update the Form that is ALREADY VISIBLE on your screen, then you need a reference to that specific form.
Getting a reference to the visible form can be done in various ways. Understanding the CONTEXT of your program will allow us to give you the easiest method to do this.
What forms are involved? Which forms create which ones, in what order? These things matter...

Referencing a Label in Form to change color at ElapsedEventHandler

So in my Form1 I have a label called lblView
I also have a class called Timer.cs
Where I have:
public TriageTimer(int ticket_num, int alert_time_in_sec, int error_time_in_sec)
{
this.id = ticket_num;
this.counter.Elapsed += new ElapsedEventHandler(this.count);
this.counter.Interval = 1000;
this.alert_timer.Elapsed += new ElapsedEventHandler(this.alert_sound);
this.alert_timer.Interval = alert_time_in_sec;
this.error_timer.Elapsed += new ElapsedEventHandler(this.error_sound);
this.error_timer.Interval = error_time_in_sec;
this.alert_timer.AutoReset = false;
this.error_timer.AutoReset = false;
this.alert_timer.Enabled = true;
this.counter.Enabled = true;
this.error_timer.Enabled = true;
}
The primary focus is the
this.alert_timer.Elapsed += new ElapsedEventHandler(this.alert_sound);
this.error_timer.Elapsed += new ElapsedEventHandler(this.error_sound);
I tried adding:
lblView.ForeColor = System.Drawing.Color.Green;
into alert_sound but I get the error lblView does not exist in the current context. I have looked up this error and found a few answers on stackoverflow that have solutions like; creating a method in the class to write something in the lbl and just call it from the form.
However my question is specifically trying to get the label fontcolor to change when it hits these Events (alert_sound & error_sound) So is there a way to reference the label that is in Form1 from Timer.cs?

but I get the error lblView does not exist in the current context.
YES, since the label control instance is present in your FORM, you will have to access it through a reference of that form. You can pass a FORM reference while calling that class method and using that form instance access the label control. Also, the FORM must be opened.

Adding a form to a splitcontainer from a child form

I'm trying to add a form to a SplitContainer from a child form. I can do it from the forms parent using this.
Lockdown.MainForm form = new Lockdown.MainForm(true);
form.MdiParent = this;
form.TopLevel = false;
form.Dock = DockStyle.Fill;
this.splitContainer.Panel2.Controls.Add(form);
form.Show();
But I can't figure out how to do it from a child of the parent form.
Any help is appreciated.

Here's how I solved the problem. I passed a reference to the child form.
MessageBoxRegister register = new MessageBoxRegister(this);
register.ShowDialog();
I then saved the reference in a global variable.
Launcher launcher;
public MessageBoxRegister(Launcher launcher)
{
InitializeComponent();
this.launcher = launcher;
}
Then I could open the form into the splitContainer like this.
Lockdown.MainForm form = new Lockdown.MainForm(true);
form.MdiParent = launcher;
form.TopLevel = false;
form.Dock = DockStyle.Fill;
launcher.splitContainer.Panel2.Controls.Add(form);
form.Show();

Closing mdi child in SplitContainer

i'm developping a winforms application and i'm putting a mdi child form in splitcontainer.panel1.
when i want to close current mdi child to open another one i can't get the child form.
i'm using this code to open e new child but i want get the current child to close it :
Accueil accueil = new Accueil();
accueil.MdiParent = this;
accueil.TopLevel = false;
this.splitContainer1.Panel1.Controls.Add(accueil);
accueil.WindowState = FormWindowState.Maximized;
accueil.Size = this.splitContainer1.Panel1.ClientSize;
accueil.MinimizeBox = false;
accueil.MaximizeBox = false;
accueil.ControlBox = false;
accueil.Width = this.splitContainer1.Panel1.Width;
accueil.Height = this.splitContainer1.Panel1.Height;
accueil.Show();

Putting an MDI child window into a split container doesn't make any sense. You are turning the form into a plain control by setting its TopLevel property to false. Best not to lose the reference. But you will probably be ahead with:
while (splitContainer1.Panel1.Controls.Count > 0)
splitContainer1.Panel1.Controls[0].Dispose();
var accueil = new Accueil();
accueil.TopLevel = false;
accueil.Dock = DockStyle.Fill;
accueil.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
accueil.Visible = true;
this.splitContainer1.Panel1.Controls.Add(accueil);
Do consider using a UserControl instead, it is the sane approach with the least likely long-term confuzzlement.

Debugging Missing Label in WinForm Application

I was developing a WinForm application for a class and I ran into a bug that I can't seem to find the root of. When I run the application everything works except for an error label that was supposed to come up with incorrect user input. At first I thought I had written the event handler for it wrong, so I stopped hiding it at startup but the label is still missing. I'm not sure if I'm missing something in some back-end file or if I'm just missing something really obvious.
This is the function that creates the label.
private void InitializeErrorLabel()
{
int width = 200, height = 13,
anchorY = this.Label.Location.Y - this.Label.Size.Height - 3;
// Initialize Component
this.ErrorLabel.AutoSize = true;
this.ErrorLabel.Font = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Bold,
System.Drawing.GraphicsUnit.Point, ((byte)(0)));
this.ErrorLabel.ForeColor = System.Drawing.Color.Red;
this.ErrorLabel.Location = new System.Drawing.Point((XSize - width) / 2, (anchorY - height));
this.ErrorLabel.Anchor = System.Windows.Forms.AnchorStyles.Top;
this.ErrorLabel.Name = "ErrorLabel";
this.ErrorLabel.Size = new System.Drawing.Size(width, height);
this.ErrorLabel.Text = "Invalid User ID. Please try again!";
return;
}
and this is the function that initializes my controls:
private void InitializeComponent()
{
this.UserInput = new System.Windows.Forms.TextBox();
this.SwitchMajor = new System.Windows.Forms.RadioButton();
this.SwitchToCS = new System.Windows.Forms.CheckBox();
this.SwitchToCE = new System.Windows.Forms.CheckBox();
this.KeepMajor = new System.Windows.Forms.RadioButton();
this.AcceptValues = new System.Windows.Forms.Button();
this.Label = new System.Windows.Forms.Label();
this.ErrorLabel = new System.Windows.Forms.Label();
this.SuspendLayout();
// Initialize Components
this.InitializeLabel();
this.InitializeMainWindow();
this.InitializeUserInput();
this.InitializeSwitchMajorBtn();
this.InitializeChangeToCSBtn();
this.InitializeChangeToCEBtn();
this.InitializeAcceptValuesBtn();
this.InitializeErrorLabel();
this.ResumeLayout();
this.PerformLayout();
return;
}
Again, not really sure what I'm doing wrong here. Any help would be appreciated.
Thanks,

In what control are you adding your errorlabel ?
A normal label initialization should look like
private System.Windows.Forms.Label ErrorLabel;
this.ErrorLabel = new System.Windows.Forms.Label();
this.groupBox2.Controls.Add(this.ErrorLabel);
this.ErrorLabel.AutoSize = true;
this.ErrorLabel.Location = new System.Drawing.Point(8, 59);
this.ErrorLabel.Name = "ErrorLabel";
this.ErrorLabel.Size = new System.Drawing.Size(55, 13);
this.ErrorLabel.TabIndex = 69;
this.ErrorLabel.Text = "Address 2";
this.ErrorLabel.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
Important
The label must be added to a control like my line three. Your control can be a form in your case. Its a groupbox in my case and the group box itself must be added to myform and myform must be visible .
this.groupBox2.Controls.Add(this.ErrorLabel);

I don't see a place where you're adding the label to the form's collection of controls:
this.Controls.Add(this.ErrorLabel);
If it's not a member of the Controls collection, you won't see it.
Related to that, I wouldn't be surprised if the other buttons, checkboxes, etc you're defining are not showing up on the form either, for the same reason.
Normally this would be taken care of by the Designer.cs file automatically.

This might be an obvious answer, but it totally went over my head. I verified that my code had the this.groupBox2.Controls.Add(this.ErrorLabel); like others have mentioned here. I couldn't figure out why I wasn't seeing my label. My label was an asterisk *, and in the designer window, I size it pretty small, but I was able to see the * in the designer window. Turns out I just had to increase it's area in the designer window since it was to small when I actually rendered the App.