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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);
}

Creating custom Label in C# and passing data in events

I had been playing around with an idea for a game, and implementation was going fairly well, but I have hit a stumbling block.
Basically, I have a form, which will show talent trees. I am just going to use labels to display the relevant details, and I want to create them programmatically. The display part is working fine, the part I am having trouble with is adding an event handler to the labels.
I want to be able to pass data during the event handling, so that I can identify which specific label was clicked, but I am hitting a brick wall. So when a particular label is clicked, the name of its associated skill (just passing a string) will be sent to the event handler. Any help would be appreciated. Here is the relevant code that I have:
public void DisplayTree()
{
int i=0;
startPoint.X = 40;
startPoint.Y = 125;
foreach(SkillNode s in tree.tier1)
{
for (i=0; i < s.labels.Count;i++ )
{
//Displays a label for each available rank for a skill
s.labels.ElementAt(i).Text = (i+1).ToString()+"/"+s.maxRank.ToString();
s.labels.ElementAt(i).Location = startPoint;
startPoint.Y += s.labels.ElementAt(i).Height + 2;
s.labels.ElementAt(i).Name = "lbl"+s.name+i.ToString();
//Only enable it to be clicked if the user is at the correct rank
if (s.rank == i)
{
s.labels.ElementAt(i).Enabled = true;
}
else
{
s.labels.ElementAt(i).Enabled = false;
}
//Add Event here
//I want to pass the name of the skill with the event
this.Controls.Add(s.labels.ElementAt(i));
}
startPoint.X += s.title.Width + 5;
startPoint.Y = 125;
}
}
public void LabelClick()
{
//Code here to pick out the name of the label
}

Try this:
public void LabelClick()
{
Console.WriteLine(((Control)sender).Name);
}

When you create an event and want to follow the official C# styleguide, you follow the following pattern:
public delegate void {YourName}EventHandler(object sender, {YourName}EventArgs args);
public event {YourName}EventHandler EventName;
Every information about what happened in the event or can be manipulated by the subscriber is stored in a class that inherits EventArgs. The delegate also contains a reference to the sender, which is the object that fires the event.
When you fire an event you do the following, regularly in a protected method that has the same name as the Event with an "On" as prefix:
EventName?.Invoke(this, new {YourName}EventArgs() { Initialize Stuff });
As you can see, you can work with the sender and identify the object. In your case you could also change object sender to UIElement sender (or similar) to make it easier to identify stuff without a cast.

WPF WebBrowser scroll on reload

I have a System.Windows.Controls.WebBrowser. It has some html that is coming from another document that the user is editing. When the html changes, what I want to do is update the WebBrowser's html, then scroll the WebBrowser back to wherever it was. I am successfully cacheing the scroll offset (see How to retrieve the scrollbar position of the webbrowser control in .NET). But I can't get a callback when the load is complete. Here is what I have tried:
// constructor
public HTMLReferenceEditor()
{
InitializeComponent();
WebBrowser browser = this.EditorBrowser;
browser.LoadCompleted += Browser_LoadCompleted;
//browser.Loaded += Browser_Loaded; // commented out as it doesn't fire when the html changes . . .
}
private void Browser_LoadCompleted(object sender, System.Windows.Navigation.NavigationEventArgs e)
{
CommonDebug.LogLine("LoadCompleted");
this.ScrollWebBrowser();
}
private void ScrollWebBrowser()
{
WebBrowser browser = this.EditorBrowser;
ReferenceHierarchicalViewModel rhvm = this.GetReferenceHierarchichalViewModel();
int? y = rhvm.LastKnownScrollTop; // this is the cached offset.
browser?.ScrollToY(y);
}
The LoadCompleted callbacks are firing all right. But the scrolling is not happening. I suspect the callbacks are coming too soon. But it is also possible that my scroll method is wrong:
public static void ScrollToY(this WebBrowser browser, int? yQ)
{
if (yQ.HasValue)
{
object doc = browser?.Document;
HTMLDocument castDoc = doc as HTMLDocument;
IHTMLWindow2 window = castDoc?.parentWindow;
int y = yQ.Value;
window?.scrollTo(0, y);
CommonDebug.LogLine("scrolling", window, y);
// above is custom log method; prints out something like "scrolling HTMLWindow2Class3 54", which
// at least proves that nothing is null.
}
}
How can I get the browser to scroll? Incidentally, I don't see some of the callback methods others have mentioned, e.g. DocumentCompleted mentioned here does not exist for me. Detect WebBrowser complete page loading. In other words, for some reason I don't understand, my WebBrowser is different from theirs. For me, the methods don't exist.

how to hide on EditText soft keyboard windows 8 Metro Application?

I'm having an EditText and a Button in my Frame using C#. After writing inside the edit field and clicking on the Button, I want to hide the virtual soft keyboard.

Add a dummy button and set focus to it and the keyboard will be hidden.

Thanks for your question.
i have get a better solution for this problem. like this
first we can add handler in xaml
<Grid x:Name= Tapped="Grid_Tapped_1">
......
</Grid >
then we focus current page like follow. it works well.
private void Grid_Tapped_1(object sender, TappedRoutedEventArgs e)
{
this.Focus(FocusState.Programmatic);
}

You cannot. There is more information on the behavior of the Input Hosting Manager and Soft Keyboard and you can register to know when it shows or becomes hidden. But, you cannot programmatically control whether it's up or down.

When the textbox that showed the virtual keyboard has it’s propery IsEnabled set to false, the virtual keyboard disappears. We can immediately set is to true after that and the virtual keyboard will remain hidden. Just like this:
MyTextBox.KeyDown += (s, a) => {
if (a.Key == VirtualKey.Enter) {
MyTextBox.IsEnabled = false;
MyTextBox.IsEnabled = true;
}
};

Try to set the IsReadOnly property of the Textbox`.
I'm doing something "similar"
private void textbox_input_LostFocus(object sender, RoutedEventArgs e)
{
textbox_input.IsReadOnly = false;
}
private void textbox_input_Tapped(object sender, TappedRoutedEventArgs e)
{
if(e.PointerDeviceType != Windows.Devices.Input.PointerDeviceType.Mouse)
textbox_input.IsReadOnly = true;
else
textbox_input.IsReadOnly = false;
}
With this snipped I suppress the keyboard if the user isn't using the mouse...
Also the KeyDown event is fired while the textbox is readonly so you could use the data directly to set your viewmodel and update over it your textbox ;)

There is a solution which can hide the touch-keyboard by setting the container's IsTabStop=true automaticly after clicking your Button as "submit".
But, btw, I've noticed that the next time entering that page, the EditText (supposed to be a TextBox) will be auto-focused, and have the touch-keyboard showed. Maybe you'd better Disable the EditText after submitting. (seems to finish and block the input operation)

I had the same problem, only with a little difference.
When I switched from a textbox to a datepicker the softkeyboard won't disappear.
I tried all of your suggestions, but nothing worked like it should. Every time my datepicker had a strange behaviour, after I tried one of the above solutions (Or some of other stackoverflow threads).
After some time I found something via Google, which worked like a charm. HERE
In the comment section Dusher16 wrote a very clean solution, which works also for WinRT / Win8 / Win8.1 / Metro or how you will call it.
Create a new class:
using System.Runtime.InteropServices;
using Windows.Devices.Input;
namespace Your.Namespace
{
public static class TouchKeyboardHelper
{
#region < Attributes >
private const int WmSyscommand = 0x0112; // Flag to received/send messages to the system.
private const int ScClose = 0xF060; // Param to indicate we want to close a system window.
#endregion < Attributes >
#region < Properties >
public static bool KeyboardAttached
{
get { return IsKeyboardAttached(); }
}
#endregion < Properties >
#region < Methods >
[DllImport("user32.dll")]
private static extern int FindWindow(string lpClassName, string lpWindowName); // To obtain an active system window handler.
[DllImport("user32.dll")]
private static extern int SendMessage(int hWnd, uint Msg, int wParam, int lParam); // To send a message to the system.
/// <summary>
/// To detect if a real keyboard is attached to the dispositive.
/// </summary>
/// <returns></returns>
private static bool IsKeyboardAttached()
{
KeyboardCapabilities keyboardCapabilities = new KeyboardCapabilities(); // To obtain the properties for the real keyboard attached.
return keyboardCapabilities.KeyboardPresent != 0 ? true : false;
}
/// <summary>
/// To close the soft keyboard
/// </summary>
public static void CloseOnscreenKeyboard()
{
// Retrieve the handler of the window
int iHandle = FindWindow("IPTIP_Main_Window", ""); // To find the soft keyboard window.
if (iHandle > 0)
{
SendMessage(iHandle, WmSyscommand, ScClose, 0); // Send a close message to the soft keyboard window.
}
}
#endregion < Methods >
}
}
And in for example some XAML.cs file you add the following lines:
private void DatePicker_GotFocus(object sender, RoutedEventArgs e)
{
if (TouchKeyboardHelper.KeyboardAttached)
TouchKeyboardHelper.CloseOnscreenKeyboard();
}

Method executing several times even though it is called once

I am doing a project which includes dynamic controls creation and removal from the WinForm,
So I decided to that part on a small test project.
Test project has two files Form1.cs and NewControls.cs. This program creates additional buttons whenever user clicks an Add button already on the form.And removes the newly created button when it is clicked (self removal button). Also after removal of button other button's Name, Text and their position are changed according to a local variable (controlIndex).
Form1.cs
public partial class Form1 : Form
{
static List<NewControl> newControlsList = new List<NewControl>();
public Form1()
{
InitializeComponent();
}
private void Add_Click(object sender, EventArgs e)
{
newControlsList.Add(new NewControl(newControlsList.Count));
}
public static void RemoveButton(object sender, EventArgs e)
{
NewControl tempNewControl = (NewControl)(sender as Button).Tag;
tempNewControl.RemoveControl();
newControlsList.Remove(tempNewControl);
MessageBox.Show("Removed!");
foreach (NewControl tempcontrol in newControlsList)
{
tempcontrol.controlIndex = newControlsList.IndexOf(tempcontrol);
tempcontrol.PlaceControl();
}
}
}
NewControl.cs
class NewControl
{
public int controlIndex = 0;
Button newButton = new Button();
public NewControl(int index)
{
controlIndex = index;
PlaceControl();
}
public void RemoveControl()
{
newButton.Dispose();
Form1.ActiveForm.Controls.Remove(newButton);
}
public void PlaceControl()
{
newButton.Tag = this;
newButton.Name = "btn" + controlIndex.ToString("D2");
newButton.Text = "btn" + controlIndex.ToString("D2");
newButton.Size = new Size(100, 20);
newButton.Left = controlIndex * 100;
Form1.ActiveForm.Controls.Add(newButton);
newButton.Click += new EventHandler(Form1.RemoveButton);
}
}
Program works nearly as expected. Problem is the MessageBox which I used in form1.cs in RemoveButton() fires many time (as opposed to just one time), which implies whole method being executed several times. Actually I pasted that MessageBox for debugging (sort of).
Since I cannot debug the application as when "Form1.ActiveForm.Controls.Add(newButton);" statement is executed, debugger Throws NullReferenceException, as there is not an active form while debugging.
I know that's like a bonus question but I thought to just put it there. I am a beginner and can't see the way through both the problems. 1st problem is really important for my original project as it will cause problem when many controls are added.

I think it is because you call PlaceControl from Form1.cs AND in the constructor of the NewControl class, Because you say newButton.Click += new EventHandler(Form1.RemoveButton);.
You are adding EventHandlers, so there can be more of them.
So when you call placeControl multiple times, you've got multiple event handlers, i think.

Probably the EventHandler hasn't been removed by RemoveButton. (I've been working in java most recently so my terms might be a little off for C#.) Suggestion: set control visibility to true when you want it and false otherwise rather than adding and removing.

Everytime a button is removed you go over your existing list of controls, and you call "PlaceControl", which attaches yet another handler.
foreach (NewControl tempcontrol in newControlsList)
{
tempcontrol.controlIndex = newControlsList.IndexOf(tempcontrol);
tempcontrol.PlaceControl();
}
Remove the above code block from RemoveButton, and you will see that your dynamically added buttons will each only trigger the event once.

In your RemoveButton event you loop on each button and call again PlaceControl.
The only reason is to reposition the remainder controls.
I think it's better a call to a separate method that do only this work.
public void RepositionControl()
{
newButton.Left = controlIndex * 100;
}
this will prevent to mess with event handlers added more than one time