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Navigating between user controls in same form

I have a windows form that allows different user controls to show and be hidden by different button.
I would like this user controls to communicate directly with each other and change values etc.
For example usercontrol1 below
User will fill form, then when they click Proceed, usercontrol1 should close and usercontrol2 should now be visible with user information picked and displayed as follows
So far I have the code below
private void btnProceed_Click(object sender, EventArgs e)
{
string name = tbName.ToString();
string email = tbEmail.ToString();
string phone = tbPhone.ToString();
string color = tbColor.ToString();
this.Hide();
UserControl2 u2 = new UserControl2();
MainForm f1 = new MainForm();
f1.panelMain.Controls.Add(u2);
f1.listView1.Items.Add(new ListViewItem(new[]{
name,
email,
phone,
color}));
}
It does not work. Only the usercontol1 is hidden and I'm left with a blank.
What I'm I doing wrong?
(Using visual studio 13 and c# language)

You are adding the new usercontrol to a new instance of MainForm. You can't see it because this new instance is never shown. To avoid this problem in the simplest possible way you pass the instance of the current MainForm to the UserControl constructor, keep that instance stored in a global variable of the UserControl and use that instance when you need to switch the two usercontrols.
In MainForm.cs (when you create the first usercontrol)
UserControl1 uc = new UserControl1(this);
.....
In UserControl1.cs
public class UserControl1
{
MainForm _current;
public UserControl1(MainForm f)
{
InitializeComponent();
_current = f;
}
private void btnProceed_Click(object sender, EventArgs e)
{
.....
UserControl2 u2 = new UserControl2();
_current.panelMain.Controls.Add(u2);
u2.listView1.Items.Add(new ListViewItem(new[]{
name,
email,
phone,
color}));
}
}
This will be problematic to correctly handle for other tasks. I would recommend to redesign your application to let the MainForm decide which usercontrol to show when needed.
In this approach you use events to get informed in MainForm.cs when the user clicks the UserControl1, so you get this in MainForm.cs
UserControl1 uc = new UserControl1();
uc.UserClick += UserAdded;
.....
where UserAdded is a method of MainForm that received the info about the new user though the class UserInfoArgs
public void UserAdded(UserControl1 sender, UserInfoArgs args)
{
sender.Hide();
UserControl2 u2 = new UserControl2();
this.panelMain.Controls.Add(u2);
u2.listView1.Items.Add(new ListViewItem(new[]{
args.name,
args.email,
args.phone,
args.color}));
}
And in UserControl1 you add the delegate, the event and raise the event when you need to communicate to MainForm the info about your new user.
public class UserControl1
{
public delegate void onClick(UserControl1 sender, UserInfoArgs args);
public event onClick UserClick;
....
private void btnProceed_Click(object sender, EventArgs e)
{
UserInfoArgs args = new UserInfoArgs()
{
name = tbName.Text,
email = tbEmail.Text,
phone = tbPhone.Text,
color = tbColor.Text
};
if(UserClick != null)
UserClick(this, args);
}
public class UserInfoArgs
{
public string name {get;set;}
public string email {get;set;}
public string phone {get;set;}
public string color {get;set;}
}

I think using backgroundworker control for this actually works for your case .
private void btnProceed_Click(object sender, EventArgs e)
{
string name = tbName.ToString();
string email = tbEmail.ToString();
string phone = tbPhone.ToString();
string color = tbColor.ToString();
string a = " "+name+" "+email+" "+phone+" "+color;
backgroundWorker1.RunWorkAsync(a);//passing the variables to the backgroundWorker
}
And then in backgroundWorker_doWork(),you can populate the data you're getting as you like .

You are overcomplicating things. You can just layer the two controls on your UI on the same position, and set the second control's Visible property to False.
Make the first user control expose an event for the button's click (or just expose the button so you can access its Click event), so that you can detect that mouse click from the main form. Then, when the listener for that button is called; the main form can get the data out of the first control, use it to initialize the second control, and then hide the first one and show the second one.

How to return to the calling method after calling a windows Form in c#?

I have a method, where I call a new Windows Form in Class A. And in the new Form, I use a Dropdown menu and store the selected Item from the Dropdown in a variable, called selectedItem.Now I have to access this selectedItem in Class A. I use the following code.
public class A
{
public method callingmethod()
{
ExceptionForm expform = new ExceptionForm();
expform.Show();
string newexp = expobj.selectedexception;
}
}
And my code in New Form,
public partial class ExceptionForm : Form
{
public string selectedexception = string.Empty;
private void btnExpSubmit_Click(object sender, EventArgs e)
{
selectedexception = this.comboBox1.GetItemText(this.comboBox1.SelectedItem);
this.Close();
return;
}
}
Now After clicking on Submit button, I get the correct value in selectedItem, But I could not pass it to Class A. How to retun to Class A?

If you are ok with posting ExceptionForm over parent form by disabling it, go for ShowDialog. But, if you do not wish to disable parent for and continue popping ExceptionForm as a new and independent window, try eventing back to parent form. Here I show an example on how to do so:
public partial class ExceptionForm : Form
{
public delegate void SelectValueDelegate(string option);
public event SelectValueDelegate ValueSelected;
private void btnExpSubmit_Click(object sender, EventArgs e)
{
this.Close();
if (this.ValueSelected!= null)
{
this.ValueSelected(this.comboBox1.GetItemText(this.comboBox1.SelectedItem));
}
return;
}
}
And in calling class:
public class A
{
public method callingmethod()
{
ExceptionForm expform = new ExceptionForm();
expform.ValueSelected += ExceptionForm_ValueSelected;
expform.Show();
}
private void ExceptionForm_ValueSelected(string option)
{
string newexp = option;
// Do whatever you wanted to do next!
}
}

Use ShowDialog() method.
expform.ShowDialog();
string newexp = expobj.selectedexception;

Send text to texbox in another form without making new windows

I need to make windows forms program, that:
a) shows 2 forms with one textbox and one button each
b) when you press the button on one form, program copies text from that form to second form
c) when you press the button on the second form, program copies text from that form to first form
I've tried several different aproaches and got bogged down in encapsulation problems, since both forms has to be in separate instances, right? I've managed to make it work, so it creates new instance of form with new text in textbox every time you click, but after several steps I ended up with screen full of new windows and I need it to show only 2 windows through whole runtime.

Create the windows in your Main method, but don't show them immediately, then access them through the static properties:
public static class Program {
public static Form1 Form1 { get; private set; }
public static Form2 Form2 { get; private set; }
public static Int32 Main(String[] args) {
using( Program.Form1 = new Form1() )
using( Program.Form2 = new Form2() ) {
Application.Run( Program.Form1 ); // Form1's `Load` method would then show `Form2`
}
Program.Form1 = Program.Form2 = null;
return 0;
}
}
Form1 (is responsible for showing Form2 because Application.Run only shows a single form itself):
public class Form1 : Form {
protected override void OnLoad(...) {
Program.Form2.Show();
}
private void Button1_Click(...) {
Program.Form2.TextBox1.Text = this.textBox1.Text;
}
}
Form2 (you need to expose its TextBox via a public property):
public class Form2 : Form {
public TextBox TextBox1 { get { return this.textBox1; } }
}

Here's an example that shows how to pass a reference to the first form, into the second form using its Constructor. That reference is stored at class level so it can be used later. The exact same code/form is being used for both instances:
public partial class Form1 : Form
{
private Form1 target = null;
public Form1()
{
InitializeComponent();
this.Text = "Instance #1";
this.target = new Form1(this);
this.target.Text = "Instance #2";
this.target.Show();
}
public Form1(Form1 target)
{
InitializeComponent();
this.target = target;
}
private void button1_Click(object sender, EventArgs e)
{
if (this.target == null || this.target.IsDisposed)
{
this.target = new Form1(this);
this.target.Show();
}
this.target.textBox1.Text = this.textBox1.Text;
}
}

got bogged down in encapsulation problems, since both forms has to be in separate instances, right?
"encapsulation" immediately made me think of nested classes. The quintessential use case is for a class that is not/should not be used anywhere except in the containing class.
The idea is to allow clients to instantiate Form1 but have no access to Form2 or any of its members. If you need to expose anything from Form2 I suggest you write Form1 properties so that the client sees everything coming from Form1 only.
public class Form1 : Form {
protected Form Sibling { get; set; }
public Form1() {
Sibling = new Form2(this);
}
protected override void OnLoad(...) {
Sibling.Show();
}
private void Button1_Click(...) {
Sibling.TextBox1.Text = this.textBox1.Text;
}
protected class Form2 : Form {
protected Form Sibling { get; set; }
public Form1 ( Form mySibling ) {
Sibling = mySibling;
}
private void Button1_Click(...) {
Sibling.TextBox1.Text = this.textBox1.Text;
}
} // Form2
} // Form1

Accessing Form's Controls from another class

I have a windows forms application with some controls added to the designer. When I want to change something (LIKE) enabling a text box from inside the Form1.cs, I simply use:
textBox1.Enabled = true;
but now I have a separated class called class1.cs.
How could I enable textBox1 from a static function class1.cs?
NOTE: I did not try any code because I am totally clueless about doing this.

EDIT: Lot of edit.
public partial class Form1 : Form
{
// Static form. Null if no form created yet.
private static Form1 form = null;
private delegate void EnableDelegate(bool enable);
public Form1()
{
InitializeComponent();
form = this;
}
// Static method, call the non-static version if the form exist.
public static void EnableStaticTextBox(bool enable)
{
if (form != null)
form.EnableTextBox(enable);
}
private void EnableTextBox(bool enable)
{
// If this returns true, it means it was called from an external thread.
if (InvokeRequired)
{
// Create a delegate of this method and let the form run it.
this.Invoke(new EnableDelegate(EnableTextBox), new object[] { enable });
return; // Important
}
// Set textBox
textBox1.Enabled = enable;
}
}

This is just another method:
TextBox t = Application.OpenForms["Form1"].Controls["textBox1"] as TextBox;

You shouldn't really change UI controls in your Form from your class1, but instead create a method or a property in class1 that would tell if the textbox should be enabled or not.
Example:
// I changed the name class1 to MySettings
public class MySettings
{
public bool ShouldTextBoxBeEnabled()
{
// Do some logic here.
return true;
}
// More generic
public static bool SetTextBoxState(TextBox textBox)
{
// Do some logic here.
textBox.Enabled = true;
}
// Or static property (method if you like)
public static StaticShouldTextBoxBeEnabled { get { return true; } }
}
Then in your form:
MySettings settings = new MySettings();
textBox1.Enabled = settings.ShouldTextBoxBeEnabled();
// Or static way
textBox1.Enabled = MySettings.StaticShouldTextBoxBeEnabled;
// Or this way you can send in all textboxes you want to do the logic on.
MySettings.SetTextBoxState(textBox1);

You can pass the instance of your Form to the class
MyForm frm = new MyForm();
MyClass c = new MyClass(frm);
Then your class can take that instance and access the textbox
public class MyClass
{
public MyClass(MyForm f)
{
f.TextBox1.Enabled = false;
}
}
The design does not look OK
It is better to call the class in your form and based on the value returned, manipulate the textbox
//MyForm Class
MyClass c = new MyClass();
c.DoSomethings();
if(c.getResult() == requiredValue)
textBox1.enabled = true;
else
textBox1.enabled = false;
//MyForm Class ends here
UPDATE
public class Class1
{
public static int SomeFunction()
{
int result = 1;
return result;
}
public static void SomeFunction(out int result)
{
result = 1;
}
}
Usage
if(Class1.SomeFunction() == 1)
textBox1.Enabled = true;
else
textBox1.Enabled = false;
OR
int result = 0;
Class1.SomeFunction(out result);
if(result == 1)
textBox1.Enabled = true;
else
textBox1.Enabled = false;

You could let your class1 have an event to enable the Textbox.
public class Class1
{
public event Action<object, EventArgs> subscribe ;
private void raiseEvent()
{
var handler = subscribe ;
if(handler!=null)
{
handler(this,EventArgs.Empty);//Raise the enable event.
}
}
}
Let the class containing the TextBox subscribe to it somehow. In TextBox wrapper class
public class TextBoxWrapper
public void EnablePropertyNotification(object sender, EventArgs args)
{
TextBox1.Enabled = true ; //Enables textbox when event is raised.
}
public TextBoxWrapper()
{
class1Instance.subscribe+=EnablePropertyNotification ;
}

To access/modify a Form Element property, just write this in your outside Class.
Form1.ActiveForm.Controls["textBox1"].Enabled = true;
Where textBox1 is the variable name of TextBox.
What this actually does: Gets the active Form object's control specified by the name in string.
WARNING: Active form means the form which is currently open and focused on. If you do something else on your computer, with your minimized WindowsForm application, the Form1.ActiveForm will not get the form, instead, it will give null, which can lead to errors later. Be careful!

based on the answer from #vr_driver you can do that to avoid problems with other containers like groupbox, panels...
TextBox t = Application.OpenForms["Form1"].Controls.Find("textBox1", true)[0] as TextBox;

In this example you have a form called Main.cs and a class called MyClass:
In MyClass (Note: the name of my Form Class = 'Main'):
Main ui = new Main();
ui.toolStripProgressBarStickers.PerformStep();
In (FormName).Designer.cs so in my case Main.designer.cs change the appropriate control from 'private' to 'public':
public System.Windows.Forms.ToolStripProgressBar toolStripProgressBarStickers;
This solved it for me.
Thanks, Ensai Tankado

I had to do this at work and didn't find that any of these answers matched what I ended up doing, so I'm showing how I made it work.
First, initialize a copy of your class in your load event.
NameOfClass newNameofClass;
Then you want to bind to your class (in the load event):
textBox1.DataBindings.Add(new Binding("Enabled", newNameofClass, "textBox1Enabled"));
In your class, do the following:
private bool textBox1Enabled = false;
public bool TextBox1Enabled
{
get
{
return textBox1Enabled;
}
set
{
textBox1Enabled = value;
}
}
The false setting will initialize your textbox to being disabled
Set textBox1Enabled to true if you want to enable by default.
If you have other logic to enable/disable the textbox, simply modify the value of textBox1Enabled accordingly.

Very easy:
Create an Instance of your Form Object where want to access the Elements from.
Form1 ui = new Form1();
and now change the Form Elements to "public" - like this in the Designer Code:
...
public System.Windows.Forms.TextBox textBox6;
...
Now you can access them like this in your Code:
ui.textBox6 ...

I had the same problem. I used windows forms & Visual Studio to generate a UI in a utility with textbox, checkbox, and button controls but ALL the code was in the same class.
I'm rewriting the utility now that I know "more" OOP concepts and created actual objects and separate classes. I too had problems getting the separate classes to be able to access the form controls and any shared methods that are in the form class. I tried the various suggestions in this thread as well as other threads but none of those solutions worked for me.
What worked for me (not sure if its the right thing to do or not) was I had each class that needed to access the controls and forms methods inherit from the Form.
Here is the relevant part of the Form.cs file:
namespace Utility
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public void WriteNote(string noteText, bool asHeading = false)
{
//Writes Messages to the Message box in the UI
Font font1 = new Font(this.ResultsTB.Font, FontStyle.Bold);
Font font2 = new Font(this.ResultsTB.Font, FontStyle.Regular);
if (asHeading)
this.ResultsTB.Font = font1;
else
this.ResultsTB.Font = font2;
this.ResultsTB.AppendText(noteText + "\r\n");
}
My Form contains a textbox called DirTB and a method called "WriteNote" that writes info to another textbox called ResultsTB. Here is the class (at least as far down as the first successful call of the WriteNote method from the Form:
namespace Utility
{
public class AppServerDTO : Form1
{
#region App Server attributes
//attributes listed here
#endregion App Server attributes
#region AppServerDTO Constructor
public AppServerDTO()
{
//These methods verify and set all the attributes
VerifyInstallFolder();
}//end of constructor AppServer
#endregion AppServerDTO Constructor
#region AppServerDTO class methods
public void VerifyInstallFolder()
{
string keypath = string.Empty;
string locationVerification = DirTB.Text + #"\SomeText";
for (int i = 0; i < 4; i++) //allows 3 attempts to get the install folder right
{
if (Directory.Exists(locationVerification))
{
i = 4;//Kills the loop
}
else if (!Directory.Exists(locationVerification))
{
locationVerification = DirTB.Text + #"\SomeMoreText";
}
else if (!Directory.Exists(locationVerification))
{
WriteNote("The directory listed in the Install Directoy box is not reachable.");
WriteNote("Please select the correct directory.");
WriteNote("The correct directory is the folder that contains the ApplicationUpdates & UpdateManager folders.");
WriteNote(#"i.e. C:\Somewhere or D:\Someplace\Somewhere");
var folderpath = FolderPrompt(#"C:\");
DirTB.Text = folderpath; //updates the install folder textbox to the new location
keypath = folderpath;
i++;
}
}//end for loop
}//end VerifyInstallFolder
As long as you are very careful with what you mark as public vs private, it should be ok.

This is how you should do :
I wrote the code below in my form class :
public static Form1 form = null;
private delegate void SetImageDelegate(Image image);
public Form1()
{
InitializeComponent();
form = this;
}
public static void SetStaticImage(Image image)
{
if (form != null)
form.pic1.Image = image;
}
private void setImage(Image img)
{
// If this returns true, it means it was called from an external thread.
if (InvokeRequired)
{
// Create a delegate of this method and let the form run it.
this.Invoke(new SetImageDelegate(setImage), new object[] { img });
return; // Important
}
// Set textBox
pic1.Image = img;
}
and the code below should be in anouther class :
Form1 frm= Form1.form;
frm.pic1.Image = image;
Note that i changed private static Form1 form = null; to public static Form1 form = null;
Good Luck ... Written by Hassan Eskandari :)

Pass variable between forms when clicking button

I have two Forms. One with where all the main code is being executed. And the other form is displayed when clicking a menu item by using this method:
Form2 videoSettings = new Form2();
private void videoToolStripMenuItem_Click(object sender, EventArgs e)
{
videoSettings.Show();
}
The form which is then opened containsfields where the user gets to set some settings for the application.
Then when clicking the "save" button I want this variable: public int deviceIndex;
to be fetched from the original Form.
So I'm wondering if I can add any event or something in Form1 which detects when the save button is clicked in videoSettings (Form2)?

I would do it a different way. I'd separate the code between the UI handling and the business logic layers. So your scenario would run in such a way:
The first form issues an event notifying that the button with certain semantics has been activated. The data needed for the processing is included into the event's data.
The business logic listens to this event, and decides to issue a command on the second form. It calls an appropriate method on the form's class, passing the needed information as a parameter (and maybe preprocessing the parameter if needed).
The second form receives the command from the business logic and updates the view.
This way the problem doesn't arise at all.
Example: (I'm not the winforms expert, beware it can be totally wrong from the POV of best winforms practices.)
Part 1 (first form):
class ProcessingActivatedEventArgs : EventArgs
{
public ProcessingActivatedEventArgs(int data) { MoreData = data; }
public int MoreData { get; protected set; }
}
class Form1 : Form
{
private int currentData;
public event EventHandler<ProcessingActivatedEventArgs> ProcessingActivated;
void OnButtonClick(object sender, EventArgs args)
{
// ...
if (ProcessingActivated != null)
ProcessingActivated(new ProcessingActivatedEventArgs(currentData));
}
}
Part 2: (business logic)
class Controller
{
Form1 f1;
Form2 f2;
void StartFirstForm()
{
f1 = new Form1();
f1.ProcessingActivated += OnProcessingActivated;
f1.Show();
}
void OnProcessingActivated(object sender, ProcessingActivatedEventArgs args)
{
int data = args.MoreData;
f1.DisableProcessingRequests();
model.ProcessingFinished += OnProcessingFinished;
model.StartProcessing(data);
if (data > 0)
f2.DisplayDataProcessing(0, data);
else if (data < 0)
f2.DisplayDataProcessing(data, 0);
else
throw new SomeCoolException("impossible data");
}
}
Part 3: (second form)
class Form2 : Form
{
public void DisplayDataProcessing(int lower, int upper)
{
// ... update the UI
}
}
Note that this implementation ties the Controller and forms tighter than it could be done. In WPF, the decoupling is achieved by using the appropriate DataContext (but I don't know how to do it properly in WinForms).

Let me suggest another way, something between the simplest ShowDialog() and the elaborated way of separation between business logic and interface.
I wish to create a new event in Form2. I call this event SettingsSaved
In Form2 add as global declaration
public delegate void SettingsSavedEventHandler(object sender, SettingsSavedEventArgs e);
public event SettingsSavedEventHandler SettingsSaved;
and in the cmdSave_Click event
if(SettingsSaved != null)
{
SettingsSavedEventArgs ss = new SettingsSavedEventArgs() { DeviceIndex = deviceIndex};
SettingsSaved(this, ss);
}
the skeleton for the class SettingsSavedEventArgs
public class SettingsSavedEventArgs: EventArgs
{
public int DeviceIndex {get; set;}
// Other settings could be added here
}
now in the code calling the Form2 we can subscribe to the event and get notified when the user clicks on the Form2 Save button
Form2 videoSettings = new Form2();
videoSettings.SettingsSaved += new SettingsSavedEventHandler(SavedHandler);
videoSettings.Show();
....
private void SavedHandler(object sender, SettingsSavedEventArgs ss)
{
int deviceIndex = ss.DeviceIndex;
}
Observer Pattern

There are many suggestions, but I'd like to add my two cents.
You could use form2.ShowDialog(); which will stop the execution of your form1 thread until the form2 is closed. Which means you can just do this from form1:
Form2 videoSettings = new Form2();
//show options
videoSettings.ShowDialog();
//at this point, the user has either clicked save, cancel, or closed the form
//(because the form is closed, obviously :) )
int device = videoSettings.deviceIndex;
If you cant have it locking up your form like that, here is another way using an event in Form2:
Form2 : Form
{
public event EventHandler Saved;
OnSaveButtonClicked(...)
{
if(Saved != null) Saved(this, new EventArgs());
}
}
and then from Form1:
Form2 frm = new Form2();
frm.Saved += (s, e) =>
{
//saved button clicked, retrieve value.
//also could be handled as a method, or really any way.
};
frm.Show();

Maybe you could try to have your second form to implement INotifyPropertyChanged interface. Then when you click on Save, you Raise the PropertyChanged event, and you capture it in the first form.

You can pass information something like this
private Form1 mainForm = null;
public Form2(Form callingForm)
{
mainForm = callingForm as Form1;
InitializeComponent();
}
Then, you can access the Form1 property from Form2 like this:
//Call this in Save button click event
this.mainForm.deviceIndex;