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Load popup form cross thread

I'm having trouble manipulating forms when from another thread.
I've overcome the issue by loading the form at runtime, showing it then hiding it. This means the form is created on the right thread and can be manipulated using invokes.
This is not the right way to do it. I have 3 problems that come from using this method
I can't spawn another popup box I have to use the one I created at runtime
The forms flash briefly on load - now that I have 3 forms its pretty obvious what I'm doing.
I have to use a variable bool to hold if the popup is open or not.
If anyone could point me in the right direction It would be much appreciated. Currently my code looks like:
On Main form Load:
CallerIDfrm = new frmCallerID();
CallerIDfrm.Show();
CallerIDfrm.Hide();
to manipulate the popup Im using
delegate void StringArgReturningVoidDelegate1(string CallerIDnum, string CallerIDname, string ContactID);
private void CallerID(string CallerIDnum, string CallerIDname, string ContactID)
{
if (CallerIDfrm.InvokeRequired)
{
StringArgReturningVoidDelegate1 d = new StringArgReturningVoidDelegate1(CallerID);
CallerIDfrm.Invoke(d, new object[] { CallerIDnum, CallerIDname, ContactID });
}
else
{
if (ContactID != null || ContactID != "0")
{
CallerIDfrm.ContactID = ContactID;
}
CallerIDfrm.Mainfrm = this;
CallerIDfrm.TopLevel = true;
CallerIDfrm.TopMost = true;
CallerIDfrm.lblCallerIDname.Text = CallerIDname;
CallerIDfrm.lblCallerIDnum.Text = CallerIDnum;
CallerIDfrm.Show();
CallerIDOpen = true;
}
}
To Hide the popup until required again im using:
delegate void StringArgReturningVoidDelegate2();
private void CallerIDClose()
{
if (CallerIDfrm.InvokeRequired)
{
StringArgReturningVoidDelegate2 d = new StringArgReturningVoidDelegate2(CallerIDClose);
CallerIDfrm.Invoke(d, new object[] { });
}
else
{
try
{
CallerIDfrm.Hide();
CallerIDOpen = false;
}
catch
{
}
}
}
I've tried otherways but the Popup loads as if it is not responding and I loose access to the popup.
Ultimately I'd like to be able to spawn multiple popups and have the ability to close them from the Main Form.

What I gather from your question: You have an caller api/lib/class and you like to show CallerId on a popup form when a call is received. Have a look at Events and Event Driven programming.
The following codes has not been tested, I wrote it from top of my head. Might not compile, they are here to show an example:
Create an CallReceived event in api/lib class as follows:
public event EventHandler<CallReceivedEventArgs> CallReceived;
protected void OnCallReceived(EventArgs e)
{
var handler = CallReceived;
if (handler != null)
handler(this, e);
// Note: For C# 6.0 and later, above statements can be simplified to
// CallReceived?.Invoke(this, e);
}
Note: If you don't have access to this api/lib code, create a Gateway class and put your event in there along with mechanism to trigger it.
Also create a CallReceivedEventArgs, this will be used to transfer event data:
public class CallReceivedEventArgs : EventArgs
{
public string CallerIDnum {get; set;}
public string CallerIDname {get; set;}
public string ContactID {get; set;}
}
Now, in your api/lib class raise this event whenever a call is received:
// a call received, replace dummy values with actual values
OnCallReceived(new CallReceivedEventArgs() { CallerIDnum="5554443322", CallerIDname="SOME_NAME", ContactID="SOME_CONTACT" });
Finally in your GUI form, register to said event and process accordingly.
// inside your main form class
private CallerAPI callerApi = new CallerAPI();
// somewhere inside you main form class, register to event
// from your use case, I would place it inside Main Form's constructor
callerApi.CallReceived += callerApi_Callreceived;
// receive event
void callerApi_Callreceived(object sender, CallReceivedEventArgs e)
{
var callerIDnum = e.CallerIDnum;
// etc.
// show callerId form with details
// you need to change frmCallerID's constructor accordingly
CallerIDfrm = new frmCallerID(e.CallerIDnum, CallerIDname, ContantID);
// to be able to track opened popups, you can store them inside a list
// private List<Form> openPopupList = new List<Form>();
//
// alternatively, you can assign CallerIDnum to form's name property
// and store these inside a List<string> instead of List<Form>
openPopupList.add(CallerIDfrm);
CallerIDfrm.Show();
}
Don't forget to unregister from event.
callerApi.CallReceived -= callerApi_Callreceived;
To wrap it up:
I can't spawn another popup box I have to use the one I created at runtime
You can create and show multiple frmCallerID, independent from each other.
The forms flash briefly on load - now that I have 3 forms its pretty obvious what I'm doing.
Since new approach creates CallerID forms based on events, you won't see these form flashing. It'll open whenever a CallReceived event is received.
I have to use a variable bool to hold if the popup is open or not.
A better approach would be: Register to forms FormClosed event, and remove from openPopupList accordingly.
frmCallerID.FormClosed += frmCallerID_FormClosed;
void frmCallerID_FormClosed(object sender, EventArgs e)
{
// remove form from openPopupList
frmCallerID closedPopup = (frmCallerID) sender;
openPopupList.remove(closedPopup);
}

Disallowing interaction with background form

On my application's first run, two forms open. The topmost form needs to take priority, and disallow any interaction with the form in the background. I have tried ShowDialog() as referenced here, however this hides the form in the background which I do not wish to do. Is there a method of accomplishing this?
public Form1()
{
InitializeComponent();
if (!fileexists(#"c:\Management Tools\Absence Tracker\bin\data\tbase.skf"))
{ firstrunactions(); }
}
void firstrunactions()
{
//open the get-started form and invite user to populate serialisable objects
firstrun frwindow = new firstrun();
frwindow.ShowDialog();
}

When you are using .ShowDialog() the execution of the containing method is paused until you close the newly opened window. So make sure to do everthing else before you call .ShowDialog(). Otherwise your program gets stuck in this method. If you are calling .ShowDialog() before the background window is shown will cause problems.
But using .ShowDialog() here is totally correct and has the right functionality.
Example how not to do it (causes the same behavior like in your problem):
public Form1()
{
InitializeComponent();
//this is the wrong place for showing a child window because it "hides" its parent
Form frwindow = new Form();
frwindow.ShowDialog(this);
}
The magical place where it works:
private void Form1_Shown(object sender, EventArgs e)
{
Form frwindow = new Form();
frwindow.ShowDialog(this);
}
Edit: In your case it is enough moving if(!fileexistst...) into the Form1_Shown()-event.

Try with frwindow.ShowDialog(this);
Or instead "this" pass the other form as parameter.
Also move this part if (!fileexists(#"c:\Management Tools\Absence Tracker\bin\data\tbase.skf"))
{ firstrunactions(); }
}
in OnLoad override.

How to make a button on a form be enabled from a different form?

Im making a game with a menu that opens new forms for each level. When you complete a level, it is supposed to congratulate you through a message box (it does) and then enable the next level's button on the different menu form. So I accessed the designer and made the buttons public and tried:
new LevelMenu().button2.Enabled = true;
But that didn't work.
I also tried doing:
public event Action levelCompleted;
//then down lower i did (after it is declared that you won the level):
if (levelCompleted != null)
levelCompleted();
W1L1.levelCompleted += () => LevelMenu.button2.Enabled = true;
But that give me the error of:
An object reference is required for the non-static field, method, or property 'The_Levels.W1L1.levelCompleted'
The form i'm working with is "W1L1", and "LevelMenu" is the menu form. Thanks in advance

You basically need a reference to your instance of LevelMenu.
So when you create your "W1L1" form, you might just pass the LevelMenu to it.
public class W1L1
{
private readonly LevelMenu _levelMenu;
public W1L1(LevelMenu levelMenu)
{
this._levelMenu = levelMenu;
}
//Where you want to enable the button
this._levelMenu.button2.Enabled = true;
}
It's not the best solution, in an architectural way, but it works.
But it would be better if you create a more OOP way for enabling the button of the next level.

When you open the next level open it as a separate object as a new form. Now when the level is completed you can access the public controls on that form from the originating class. Something like this might help:
LevelMenu NextLevel = new LevelMenu();
public event Action levelCompleted;
if (levelCompleted != null)
levelCompleted();
NextLevel.button2.Enabled = true;

here's what I did I hope this helps
I created 2 Forms
Form1 = where menu is (buttons), Form2 = the game level (i.e. level 1)
then in Form2 I added an even LevelCompleted that will notify form1 that the player completed the level
//add this to form2
//the delegate
public delegate void LevelCompleted(Int32 level);
//the event
public event LevelCompleted LevelCompletedEvent;
then on Form1 (the menu form) when you create an instance of Form2 (which has the event) subscribe to it and create a handler, in my case I added it after i created the instance of Form2
private void button1_CLick(object sender, EventArgs e)
{
Form2 level1 = new Form2();
level1.LevelCompletedEvent += new Form2.LevelCompleted(level1_LevelCompletedHandler);
level1.Show();
}
//and this is the handler method
void level1_LevelCompletedHandler(int level)
{
//the logic for controlling the button states
// the level parameter can be used to indicate what is the current level completed.
if(level == 1)
{
button1.Enabled = false;
button2.Enabled = true;
}
}
Note: that in Form2 (the game level) I created a field gameOver that can be used if he did not complete the game
If in case he is permitted to go to next level, You must raise the event in this form to notify Form1 (the menu)
that he (the user) completed the level and Form1 will execute the method level1_LevelCompletedHandler(int level).
I know this is not well explained but I hope I can give you an idea on the event.

Need to define control flow and functionalities

I have a project with requirements as below,
Login form opens up and asks for user name and password.
Login Successful - Login form closes and another main form opens and all the functionalities will be added here.
In the main form there is a Call button when clicked on it, it will pop a dial pad.
When the number is entered on the dial pad and clicked "ok", control comes back to the same main form.
When logout is clicked, It wil take me to the login screen again.
For this can anybody explain me the following points:
How do I tranfer the control from one form to another?
I have to make sure when user clicks on the close 'x' , I have to log out and close the windows?
Neeed some rough class information.
Thanks in advance.
This is what i used earlier to carry data from one form to other
public partial class DialPad : Form
{
public MainGUI guiObject;
public DialPad(MainGUI mG)
{
InitializeComponent();
guiObject = mG;
}

By the sounds of it your dialler form should be a dialog..
class MyDiallerDialog : Form
{
public String DialledNumber
{
get { return this.txtNumber.Text; } // Or however the form stores its number...
}
}
class MyMainForm : Form
{
void btnCall_Click(object sender, EventArgs e)
{
using (var dialog = new MyDiallerDialog())
{
if (dialog.ShowDialog() == DialogResult.OK)
{
String number = dialog.DialledNumber;
// do something interesting with the number...
}
}
}
}

For your point no. 2
I have to make sure when user clicks
on the close 'x' , I have to log out
and close the windows?
In the event FormClosing of the form, take a look at e.ClosingReason.
So if user closes using Close Button (X), then ClosingReason would be UserClosing. So check that and then write appropriate code therein.
How do I tranfer the control from one
form to another?
For e.g
If you want to get the number in main form from Dialpad form.
1st in the contructor of main form
public static MainForm instance = null;
public string numberInMainForm = null;
public MainForm()
{
instance = this;
}
now in your dialpad form, when user enters the number, you can pass the number (or any other variable.) to main form from the dialpad form directly.
In dialpad form just write:
MainForm.instance.numberInMainForm = number;
thats it. You are done !!

let us assume you 1st form is loginform,
Suppose User press OK on the login form, so on
OK_click()
event call another form.
suppose your name of the another form is MainForm.cs then you can call using...
MainForm mf = new Mainform()
Suppose you want to close the login form when user press OK of your logIn form you can keep the order in following way..
private void OK_Click(object sender, EventArgs e)
{
. . .
// your validations
//return bool (true or false ) to confirm you have complted validations
MainForm mf = new Mainform();
mf.show(); // or you can use mf.ShowDialog();
. . .
. . .
this.close();
}
When you will close the MainForm,its control will come directly to the next line after mf.show();
To close any form use
this.close() command.
I hope this will help you ands you can start working on your project now.
EDIT:
Add a new class file named commondata.cs and in that use static variables like
public static string myString = "";
You can keep all the static functions and variables in the common file like commonData.cs so that you can modify its value from anywhere and can be used from anywhere.
Before closing your current form store the information in the static myString so even if u close the current form related information will be stored in myString & you can access it in any form using commonData.myString command.
string temp = commonData.myString;
Regards,
Sangram Nandkhile.

Changing the property of a control on another form

Basically, I have a settings window, and when you click "OK", it's suppose to apply settings to the main form (eg, set font of a control, etc), and then close.
frmmain frm = new frmmain();
frm.OLVAltBackColor = Color.Aquamarine ;
I tried that, but it only applies the settings to that instance, and you can see it if you do frm.Show();
I'm trying to make it so the already opened form has it's control's properties changed.

What you are trying to do is not working because you are creating a NEW instance of your main form and updating that rather than the first instance. It is possible to update the main form by keeping a reference to it in your settings form... but...
...it sounds like you are approaching this from the wrong direction.
Don't make the settings form dependent on the main form. Instead create the settings form from the main dialog.
class SettingsForm : Form
{
// You need to ensure that this color is updated before the form exits
// either make it return the value straight from a control or set it
// as the control is updated
public Color OLVAltBackColor
{
get;
private set;
}
}
In your main form
(I'm assuming some kind of button or menu click)
private void ShowSettingsClicked(object sender, EventArgs args)
{
using (SettingsForm settings = new SettingsForm())
{
// Using 'this' in the ShowDialog parents the settings dialog to the main form
if (settings.ShowDialog(this) == DialogResult.OK)
{
// update settings in the main form
this.OLVAltBackColor = settings.OLVAltBackColor;
}
}
}

Apply the property change to the form that already exists and is already shown instead of creating a new form and changing that one.

In this code you're creating a new instance of the frmmain. Any changes you make to that new object will happen in the new object, not the one you actually want to change.:
frmmain frm = new frmmain(); //Creating a new object isn't the way.
frm.OLVAltBackColor = Color.Aquamarine ;
What you're looking for is a way to call on the already existant frmmain class and change the property of that.
Edit, for example:
using System;
class Statmethod
{
//A class method declared
static void show()
{
int x = 100;
int y = 200;
Console.WriteLine(x);
Console.WriteLine(y);
}
public static void Main()
{
// Class method called without creating an object of the class
Statmethod.show();
}
}