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Xamarin forms xaml button click handler not fired c#

I has rey use VS 2015 with xamarin forms to create a cross platform project. I add the xaml page which contain a text box and button. In the code behind, I has code as below
public Inno()
{
InitializeComponent();
btntest.Clicked += Btntest_Clicked;
}
Private void Btntest_Clicked(object sender, EventArgs e)
{
if(string.IsNullOrEmpty(Name.Text))
{
return;
}
}
When I run the android simulator to test the page, it fire the constructor. But when I clicke the button, it not fire the click event. Anything goes wrong? Please help. Thanks

Theres a few things you can try:
hook up the event handler in the xaml, see if that works - because you are subscribing to the event in the constructor this shouldn't make a difference functionality wise.
Edit: to do this, in your xaml:
<Button Clicked="buttonClicked" />
and Press tab when intellisense prompts you to create a new handler.
as #hankide said - set a breakpoint and make sure it isn't actually entering it and that the problem isn't the code inside the event handler.

You need to make sure that your btntest object has been properly mapped to the button on the XAML side of things. By default, XAML objects don't have "names" as you may be accustomed to in WinForms or WebForms and need to have a name property assigned to them. For me, I typically have my buttons marked up as:
<Button x:Name=btntest Text="Click Me></Button>
Then in the code behind I have to find the button by name in order to wire up the event:
var testButton = this.FindByName<Button>("btntest");
testButton.Clicked += Btntest_Clicked;
From there everything works as expected.

Try this:
btntest.Clicked += new EventHandler(Btntest_Clicked);

Thanks everyone for the answer...not sure why I close the solution and re-open it, it work fine.

Winform controls not firing events - validating, validated, gotfocus

My question is why i cannot get the events of the controls to fire. My code is as follows:
private void textBox1_GotFocus(object sender, EventArgs e)
{
MessageBox.Show("WORKS");
}
Please excuse the messagebox as i ended up creating a new form just for testing purposes. My plan is when a user clicks onto a textbox it opens a new form as a dialog to select a date and then return to the original form. But i cannot get the event to fire.
After reading loads of info online including: http://msdn.microsoft.com/en-us/library/system.windows.forms.control.gotfocus%28v=vs.110%29.aspx
I cannot see how it is not firing. Any help would be greatly appreciated.
Im new to posting on forums so please go gentle with me.

Probably you didn't attach the event handler, try this on Form Load:
textBox1.GotFocus += textBox1_GotFocus;
If you don't see Form_Load event double click your form in the designer and write this code inside of it.

adding an event handler to a dynamically created checkbox (aspx, c#)

So my problem is that I want to add an event handler to a dynamically created CheckBox. I have already looked at other ways to do this, and decided that creating a dynamic table which contains my CheckBoxes is the best option for me. I have not added these CheckBoxes to the Control Tree because I need to manage the ViewState manually. Either way, my code works in every way except that my CheckBox's CheckChanged Event does not fire. I am adding this eventhandler to my CheckBox in my pageLoad event, however, any page event I try seems to give me the same results:
CheckBox chbxLv1 = new CheckBox();
chbxLv1.ID = "DymanicallyCreatedIDForIdentification";
chbxLv1.AutoPostBack = true;
chbxLv1.CheckedChanged += new EventHandler(this.checkChanged);
/* Way lower in my code */
protected void checkChanged(object sender, EventArgs e)
{
//Some code goes here which never seems to execute... grrr
}
I thought that this may be a problem with the ViewState at first and did quite a bit of research on that. I'm now thinking I am doing something dumb with adding an event handler. I'm not sure why this event never fires, but I'm a little new at adding events to a control. Do I need a delegate here?
--Roman

In order for dynamically loaded controls to be handled properly during the ASP.NET Page Lifecycle, they need to be added to the page during OnInit (or prior to LoadViewState, really) otherwise their state information will not be maintained and you can, in fact, corrupt the viewstate depending on how/where things are added in the page's control graph.

C# event handler explanation please

Could anyone please explain what and how this code below is doing/working?
RoleEnvironment.Chaning += RoleEnvironmentChaning;
private void RoleEnvironmentChanaing(object sender, RoleEnvironmentchaningnEventArgs e)
{
......
}
basically, if you could walk me through how event handling works in c#.net will be greatly appreciated.
Thanks.

Let's forget about C# for a second and think about the following scenario.
You have a button on the screen that you want the user to click, you don't know when the user will click the button and neither do you want to check constantly if the user has clicked the button. What you want to do is run a bit of custom code when the user does eventually click on a button.
Welcome to events or delegates.
Let's take a look at the button.
The Button has a Click event that you can hook your custom code onto.
i.e.
//This happens in the designer
Button button = new Button();
button.Click += new EventHandler(YourMethod);
Your method will now be called once the button has been clicked.
What happens on Click of the button? Someone will check whether or not there are subscribers to the event
if(Click != null)
{
Click(this, someEventArguments);
}

Basically that's saying: whenever the RoleEnviroment decided to trigger the "changing" event, call that method. (I assume it should be Changing rather than Chaning or Chanaing as per your code.)
In other words, events in C# are an implementation of the publisher/subscriber or observer pattern.
See my article on events and delegates for more information.

Some first page search results:
http://www.codeproject.com/KB/cs/csevents01.aspx
http://www.c-sharpcorner.com/UploadFile/ddutta/EventHandlingInNetUsingCS11092005052726AM/EventHandlingInNetUsingCS.aspx
http://msdn.microsoft.com/en-us/library/aa645739%28VS.71%29.aspx

Registering a KeyPress Event Method in C# "DialPad.Designer.CS" page

Im designing a dialerPad form using Windows form, there is a textbox which should only take numbers and not text, my problem is that when i add the code
private void txtDialedNumber_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
//Blaah Blaah Code;
}
but its not getting registered in the other DialPad.Designer.CS page. For example the fallowing code registers TextChangedEvent
this.txtDailedNumber.TextChanged += new System.EventHandler(this.txtDailedNumber_TextChanged);
Can anybody help me on this?

You should never change *.designer.cs files manually.
What you should be doing is opening the design view of your form, selecting the object, and then setting the event handler in the objects properties:
Alternatively, if you want to register event handler manually (instead of using the designer), just put it under the InitializeComponent() call in the constructor for your form.

I would try to simplify Greg's answer.
Select the text box > go to properties > events tab> KeyPress Event > select the method this.txtDailedNumber.KeyPress
You are done.