I am new to c# windows forms and I'm trying to make a GUI that has two panels. The left panel is used to display dynamically added user controls that contain buttons. The right panel is used to display dynamically added usercontrols that contain other controls: textboxes, labels, comboboxes, buttons, etc.
I've created a form1 that has the two panels. I can successfully load both panels with different UserControl.cs content by using a menu that I've added to the top of the form. When I click a menu option, form1 buttonPanel is loaded with the appropriate buttonPanel.cs content and form1 mainPanel is loaded with the appropriate mainPanel.cs content. However, when I click the button that exists on buttonPanel.cs, I can't get form1 mainPanel to change it's content.
ie: WelcomeMenu.cs has a button called btnPage2 that should change mainPanel controls to show Page2.cs usercontrol instead of Welcome.cs usercontrol.
I want to be able to use in the button click handler on UserControl.cs:
mainPanel.Controls.Clear();
UserControl usrCtl = new UserControl();
Form1.mainPanel.Controls.Add(usrCtl);
My problem seems to be that WelcomeMenu.cs cannot see or access Form1 mainPanel.
Is there a way to make this work? Or am I trying to do this the wrong way?
My reason for this method is so I can load a new buttonPanel.cs usercontrol and mainPanel.cs usercontrol for each department and then be able to change mainPanel content for each button I click in the current buttonPanel. I'm trying to avoid creating a bunch of panels on Form1 and then hiding them and only making them visible when I need them.
Update:
buttonMenu.cs
{
{
public partial class ucWelcomeMenu : UserControl
public ucWelcomeMenu()
{
InitializeComponent();
}
private void btnPage2_Click(object sender, EventArgs e)
{
Form1.mainPanel.Controls.Clear();
ucWelcome frm = new ucWelcome();
Form1.mainPanel.Controls.Add(frm);
}
}
}
Form1.mainPanel.Controls.Add(frm) generates an error on Form1.mainPanel that states:
"An object reference is required for the non-static field, method, or property 'Form1.mainPanel'
UPDATE 2:
Ok. I've searched several different links and found some helpful information. However, I am still unable to fire an event from a button click in a dynamically added UserControl.cs. I have 2 panels on Form1. menuPanel and mainPanel. They are both set to Modifiers = Public.
Here is my Form1:
namespace TestUserControl
public partial class Form1 : Form
{
private ucWelcomeMenu welc = new ucWelcomeMenu();
public Form1()
{
InitializeComponent();
ucWelcomeMenu welcomeMenu = new ucWelcomeMenu();
menuPanel.Controls.Add(welcomeMenu);
welc.ButtonClick += new EventHandler(this.CustomEvent_Handler);
}
private void CustomEvent_Handler(object sender, EventArgs e)
{
MessageBox.Show("Yes");
}
}
}
And Here is my UserControl:
namespace TestUserControl.UserControls
public partial class ucWelcomeMenu : UserControl
{
public event EventHandler ButtonClick;
public ucWelcomeMenu()
{
InitializeComponent();
}
private void btnPage2_Click(object sender, EventArgs e)
{
if (ButtonClick != null)
ButtonClick(sender, e);
}
}
}
Ok. I am definitely a little slow. I found my problem. I was Instantiating the ucWelcomeMenu twice. Once I removed the private instantiation above the constructor, the event fired just fine. Thanks for all the input. It sent me to some good links with some very helpful information.
Here is what I ended up with:
Form1 Menu Option Click Handler:
private void option1ToolStripMenuItem_Click(object sender, EventArgs e)
{
UserControl1 ctl1 = new UserControl1();
menuPanel.Controls.Add(ctl1);
ctl1.btn1Click += new EventHandler(btn1_Click);
UserControl2 ctl2 = new UserControl2();
mainPanel.Controls.Add(ctl2);
}
Button 1 Click Handler on Form1:
private void btn1_Click(object sender, EventArgs e)
{
mainPanel.Controls.Clear();
UserControl2 frm = new UserControl2();
mainPanel.Controls.Add(frm);
}
UserControl1.cs
public partial class UserControl1 : UserControl
{
public event EventHandler btn1Click;
public UserControl1()
{
InitializeComponent();
}
private void btn1_Click(object sender, EventArgs e)
{
if (btn1Click!= null)
btn1Click(sender, e);
}
}
Set the accessibility Modifiers property of mainPanel from private to internal public.
Related
This question already has answers here:
Communicate between two windows forms in C#
(12 answers)
Closed 3 years ago.
I have a usercontrol named as myUserControl.
1. myUserControl has a button.
2. The Constructor of myUserControl initializes a variable.
public partial class myUserControl : Usercontrol
{
public string test;
public myUserControl ()
{
InitializeComponent();
test = "This is test";
}
}
my Form1 has a flowlayout pannel.On my Form1.Load I add my myUserControl to a FLowLayoutPanel
private void Form1_Load(object sender, EventArgs e)
{
myUserControl muc = new myUserControl();
myFlowLayoutPannel.Controls.Add(muc);
}
now in Form1, i have a FlowlayoutPannel showing my myUserControl without an issue, what i want is when i click on the button of myUserControl, a Messagebox to be shown with the value of Test variable which defined in myUserControl.
I hope my idea is clear, of course, this is just an example to explain my question and your answer will help me to do something more.
You could add the button to the user control form using the Visual Studio Designer.
Add an event handler for button click or simply double click on the button in the designer: a Button1_Click event handler will be generated.
Define a event using EventHanlder, that the user control will raise after the button is clicked.
public partial class myUserControl : UserControl
{
public string test;
public event EventHandler<UserEventArgs> SomebuttonClicked;
public myUserControl()
{
InitializeComponent();
test = "This is test";
}
private void UserControl1_Load(object sender, EventArgs e)
{
}
private void Button1_Click(object sender, EventArgs e)
{
SomebuttonClicked(sender, new UserEventArgs
{
SomeVariable = test
}
);
}
}
public class UserEventArgs : EventArgs
{
public string SomeVariable { get; set; }
}
In your main form class, register to the event of the user control.
myUserControl1.SomebuttonClicked += MyUserControl1_SomebuttonClicked;
Finally, add the event handler function to the form:
private void MyUserControl1_SomebuttonClicked(object sender, UserEventArgs e)
{
MessageBox.Show(e.SomeVariable);
}
So I have a MainForm, in which I got a Panel.
To this I have created several UserControls that I will put in my Panel on request from different buttons.
My question is: I need to change the windowsize on MainForm depending on which UC I have in the Panel. How do I do this?
I was thinking of creating a public method in MainForm and then call it in the different UC on load, what do you think? Give me your best solutions. Thanks.
Edit: If this is to any help, this is in my MainUC-code to bring in other UC to replace MainUC in panel
private void UC1Button_Click(object sender, EventArgs e)
{
Panel MainPanel = MainForm.MainPanel;
if (!MainPanel.Controls.Contains(UC1.Instance))
{
MainPanel.Controls.Add(UC1.Instance);
UC1.Instance.Dock = DockStyle.Fill;
UC1.Instance.BringToFront();
}
else
{
UC1.Instance.BringToFront();
}
In each UserControl you can create an event which is triggered when content should change. For example you can create an event when a button is clicked
public partial class MyControl : UserControl
{
public event OnButtonClicked ButtonClicked;
public MyControl()
{
InitializeComponent();
}
private void MyButton_Click(object sender, EventArgs e)
{
if(ButtonClicked != null)
{
ButtonClicked((Button)sender);
}
}
}
public delegate void OnButtonClicked(Button button);
Then in your MainForm you can subscribe to events and change panel content and window size when appropriate.
public partial class MainForm : Form
{
MyControl myControl;
void Subscribe()
{
myControl.ButtonClicked += myControl_ButtonClicked;
}
void myControl_ButtonClicked(Button button)
{
// Change panel content
// Resize window
}
}
I'm trying to make a button that shows a message box when you click it. The button is made as a user control and it's put inside a panel container. What i want to do is when you click the button, the controls dissapear within the panel.
Code in usercontrol
public partial class UserControl1 : UserControl
{
public event EventHandler ButtonClick;
public UserControl1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
//bubble the event up to the parent
if (this.ButtonClick != null)
this.ButtonClick(this, e);
MessageBox.Show("Test"); //test if the button itself is working
}
}
Code in Form
public partial class Form1 : Form
{
UserControl1 usercontrol1 = new UserControl1();
public Form1()
{
usercontrol1.ButtonClick += new EventHandler(btnIsClicked);
InitializeComponent();
}
private void btnIsClicked(object sender, EventArgs e)
{
panel1.Controls.Clear();
}
}
Having used the code above it's not working, the button works but nothing happens in the form.
I am really new to programming and currently working on a C# Windows Forms application.
The problem is the following:
I have a Form with different objects and controls like: tabpages, textboxes, timers, etc .
I also have a UserControl form which I load into one of the main Form's tabpages.
I would like to write a code into the UserControl , how can I manipulate element properties of the main Form.
For example: when I click on a button on the UserControl form It sets the main Form's timer.Enabled control to true.
It is possible to do this, but having the user control access and manipulate the form isn't the cleanest way - it would be better to have the user control raise an event and have the hosting form deal with the event. (e.g. on handling the button click, the form could enable/disable the timer, etc.)
That way you could use the user control in different ways for different forms if need be; and it makes it more obvious what is going on.
Update:
Within your user control, you can declare an event - In the button click, you raise the event:
namespace WindowsFormsApplication1
{
public partial class UserControl1 : UserControl
{
public event EventHandler OnButtonClicked;
public UserControl1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
EventHandler handler = OnButtonClicked;
// if something is listening for this event, let let them know it has occurred
if (handler != null)
{
handler(this, new EventArgs());
}
}
}
}
Then within your form, add the user control. You can then hook into the event:
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
userControl11.OnButtonClicked += userControl11_OnButtonClicked;
}
void userControl11_OnButtonClicked(object sender, EventArgs e)
{
MessageBox.Show("got here");
}
}
}
You may want to rethink what it is you are trying to accomplish. However, to answer your question, it can be done.
The best way to do it is to make a property in your UserControl called MainForm:
public Control MainForm {
get;
set;
}
Then, in your MainForm's Load event, set the property to itself:
userControl1.MainForm = this;
Finally, in your user control, set the MainForm's timer:
protected button_click(object sender, EventArgs e)
{
timerName = "timer1";
EnableTimer(timerName);
}
private void EnableTimer(timerName)
{
var timer = MainForm.Controls.FirstOrDefault(z => z.Name.ToLower().Equals(timerName.ToLower());
if (timer != null)
{
((Timer)timer).Enabled = true;
} else {
// Timer was not found
}
}
This is very simple. It's called events. On the user control you would expose an event with a EventHandler for the form to subscribe to.
public partial class MyUserControl : UserControl
{
/// You can name the event anything you want.
public event EventHandler ButtonSelected;
/// This bubbles the button selected event up to the form.
private void Button1_Clicked(object sender, EventArgs e)
{
if (this.ButtonSelected != null)
{
// You could pass your own custom arguments back to the form here.
this.ButtonSelected(this, e)
}
}
}
Now that we have the user control code we'll implement it in the form code. Probably in the constructor of the form you'll have some code like below.
MyUserControl ctrl = new MyUserControl();
ctrl.ButtonSelected += this.ButtonSelected_OnClick;
Finally in the form code you'll have a method that subscribed to the event like the below code that will set the Timer enabled to true.
private void ButtonSelected_OnClick(object sender, EventArgs e)
{
this.Timer1.Enabled = true;
}
And that's how you allow an event on a user control on a form set an object on the form.
You can set the timer1.Modifiers property to "internal" and access it with an instance to Form1:
form1.timer1.Enabled = true;
You need to have an instance of your class Form1, not the class itself. For example:
// INVALID
Form1.timer1.Enabled = true;
// VALID
var form1 = Form1.ActiveForm;
form1.timer1.Enabled = true;
But this is not a very clean way to do this, you would rather use events as described in NDJ's answer.
You need to put the below code,
(`userControl11.OnButtonClicked += userControl11_OnButtonClicked;`)
in a separate file in Visual Studio. The other file is called 'Form1.Designer.cs', and can be found in the Solution Explorer pane under
Form1 >> Form1.cs >> Form1.Designer.cs.
Hope this helps!
I have a main parent winform in which I have implemented some features and that have a number of child windows. Now I want the functionality I have implemented to run also on the child windows.
For instance, in the parent window I am moving an image on the selection of a checkbox. Now, if this checkbox is checked then the image should also move on the all other child windows.
Note: The image moving on the parent window should disapper and should only show on the opend dialogue or child window.
Please suggest if it is possible.
Try using events.
Create an event for the parent form called ImageMoved.
The child forms should subscribe to this event, and when you move the image, you raise the event, then the child forms will know to do their thing.
Lots of different ways to do this. Simple example:
public partial class Form1 : Form {
public event EventHandler ImageMoved;
private void OnImageMoved() {
if (ImageMoved != null)
ImageMoved(this, new EventArgs());
}
private void button1_Click(object sender, EventArgs e) {
OnImageMoved();
}
private void button2_Click(object sender, EventArgs e) {
Form2 f2 = new Form2(this);
f2.Show();
}
}
Then your child forms could look something like this:
public partial class Form2 : Form {
public Form2(Form1 parentForm) {
InitializeComponent();
parentForm.ImageMoved += new EventHandler(parentForm_ImageMoved);
}
void parentForm_ImageMoved(object sender, EventArgs e) {
MessageBox.Show("Image moved");
}
}
You could also create your own EventArgs class if you want to pass more information, such as which image, etc.