I have an UWP app that controls my tv. I have some Buttons, Checkboxes etc. and keyboard controls/events. This combination causes problems. When check a checkbox and then press VirtualKey.Subtract the checkbox is unchecked and I don't want any changes through keyboard. The use of e.Handled doesn't seem to work.
How can I disable default Keyboard navigation behaviour or Keyboard Focus in a UWP App?
private async void Page_Loaded(object sender, RoutedEventArgs e)
{
Window.Current.CoreWindow.KeyDown += KeyEventHandler;
Window.Current.CoreWindow.KeyUp += KeyEventHandlerDevNull;
}
private void KeyEventHandlerDevNull(CoreWindow sender, KeyEventArgs e)
{
e.Handled = true;
}
private async void KeyEventHandler(CoreWindow sender, KeyEventArgs e)
{
e.Handled = true; //gets unset in case of default
if (MainViewModel.ControlsEnabled)
{
switch (e.VirtualKey)
{
case VirtualKey.Left:
await ButtonPressLeft();
break;
case VirtualKey.Right:
await ButtonPressRight();
break;
default:
e.Handled = false;
break;
}
}
}
Sorry if this question might be a duplicate one but I think it's different for UWP (Universal Windows Platform).
You need to implement/use your custom checkbox and override the OnKeyDown Event to prevent changes to your checkbox.
public sealed partial class MyCheckBox : CheckBox
{
public MyCheckBox()
{
this.InitializeComponent();
}
protected override void OnKeyDown(KeyRoutedEventArgs e)
{
e.Handled = true;
//your logic
}
}
Related
So, apparently I had some problem when handling keys such as F10 or F11.
I want to move the focus from current textbox into another textbox, but not in one particular textbox. So, I wrote some code to handle key:
private void checkKeys(KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
buyerName.Focus();
}
else if (e.KeyCode == Keys.F11)
{
discount.Focus();
}
}
But, if I put this into individual textbox, which kinda hassle to me. Is there any method to listen key whether in global userControl or textbox?
Edit : here's my structure that I want to ask :
Form-
|-User Control
|-TextBox
Edit 2 : here's some image might help img
To use a global keyboard listener in Winforms, you just need to add a handler to KeyUp action for the main form itself:
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
textBox1.Focus();
e.Handled = true; //To use F10, you need to set the handled state to true
} else if (e.KeyCode == Keys.F11)
{
textBox2.Focus();
}
}
Then make sure that the KeyPreview property on the main form is set to True.
The issue with the application freezing when pressing F10 is because it is waiting for another consecutive action. To bypass this simply set the Handled property on the keyevent to TRUE. This releases the unresolved event.
This is my entire form class, refactored to use a helper method as you are refering to. This works fine. But you have to make sure that the KeyPreview property on your form is True, unless your keypresses will not be matched to your event handlers.
namespace KeyTest
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
CheckKeys(e);
}
private void CheckKeys(KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
textBox1.Focus();
e.Handled = true;
}
else if (e.KeyCode == Keys.F11)
{
textBox2.Focus();
e.Handled = true;
}
}
}
}
Now in your comment you are mentioning a UserControl, if you want that, then you need to create an instance method on your UserControl class, and pass the event to that from your global keyboard event handler on your main form.
public partial class UserControl1 : UserControl
{
public UserControl1()
{
InitializeComponent();
}
public void HandleKeys(KeyEventArgs e)
{
if (e.KeyCode == Keys.F10)
{
textBox1.Focus();
e.Handled = true;
}
else if (e.KeyCode == Keys.F11)
{
textBox2.Focus();
e.Handled = true;
}
}
}
Then on your main form:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Form1_KeyUp(object sender, KeyEventArgs e)
{
CheckKeys(e);
}
private void CheckKeys(KeyEventArgs e)
{
uc1.HandleKeys(e); //Instance method on your user control.
}
}
This then works as intended.
As pointed out in one of the comments, a better way would be to override the ProcessCmdKey method on the Form base class. This would be done like so:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
userControl11.HandleKeys(keyData); // method on the userControl to handle the key code.
base.ProcessCmdKey(ref msg, keyData);
return true;
}
}
The handler on the UserControl stays more or less the same:
public void HandleKeys(Keys keys)
{
if (keys == Keys.F10)
{
nameTB.Focus();
} else if (keys == Keys.F11)
{
emailTB.Focus();
}
}
Whether this is a more correct way of doing it, I am unsure of. They certainly both accomplish the same result. The documentation shows the first method in for handling keyboard events at the form level here:
How to handle keyboard input
But states here that the ProcessCmdKey method is to provide additional handling of shortcuts and MDI accellerators.
ProcessCmdKey
I will leave that up to you to decide what is the best for your scenario. But keep it in to show how you would use it should you choose to.
You can hook up to the KeyUp event of your form.
That way, any key pressed while your form is focused will be send to you (if the control didn't handle the key).
Thanks to #Espen and #reza-aghaei for handling keys into main form. Unfortunately, I still didn't managed find a way to focus to designated textbox inside a UserControl. However, I make some dirty method which kinda crappy and un-efficient by searching child control from it's parent
//MainForm.cs
if(yourUserControl.Name)//Do some check for targeted userControl, if null can cause NullReferenceException
{
if (e.KeyCode == Keys.F10)
{
this.Controls.Find("textboxName", true).First().Focus();
e.Handled = true;
}
}
I have a calculator usercontrol, the usercontrol is added to a panel in my form:
On my main Form I have:
private void frmPOS_KeyDown(object sender, KeyEventArgs e)
{
// here I want to pass the keydown captured to my calculator
// usercontrol so the KeyDown event is fired in my usercontrol
}
In my Calculator.cs I have:
private void Calculator_KeyDown(object sender, KeyEventArgs e)
{
switch (e.KeyCode)
{
case Keys.NumPad0:
// one
lblResult.Text = "0";
break;
case Keys.NumPad1:
// one
lblResult.Text = "1";
break;
case Keys.NumPad2:
// two
lblResult.Text = "2";
break;
// .. etc
case Keys.Add:
// Plus
break;
default:
// Avoid setting e.Handled to
return;
}
e.Handled = true;
}
Any clue?
One way I have done this is by creating an event on the user control and raise it when the actual event happens. So, in the user control I would do something like...
public partial class Calculator : UserControl
{
//create an event
public event EventHandler<KeyPressEventArgs> OnKeyPressed;
public Calculator()
{
InitializeComponent();
}
private void Calculator_KeyPress(object sender, KeyPressEventArgs e)
{
//raise the event when the key press happens and someone is listening
if (OnKeyPressed != null)
{
OnKeyPressed(sender, e);
}
}
}
and then on the Main form you would subscribe to the event and handle it..
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
//subscribe to the event we create on the user control
calculator1.OnKeyPressed += new EventHandler<KeyPressEventArgs>(MyKeyPressHandlerInMainForm);
}
private void MyKeyPressHandlerInMainForm(object sender, KeyPressEventArgs e)
{
//Handle the event. Here you would write your logic.
//Since you have keypressEventArgs coming in as a parameter you would be able to
//do determine what key was pressed and all that.
}
}
enter code here
You can move your switch block to a new public method in the control, eg.:
public void HandleKeyEvent(KeyEventArgs e) { ... }
This method can be invoked from your form (and your existing control event handler if you need to keep it).
As a side note, if you set the form's KeyPreview-property to true you won't get problems with a focused control incorrectly getting the event. See MSDN for more information about this property.
Today I'm having a problem with the keyup event not working on a custom theme.
public Main()
{
InitializeComponent();
tbResolveS2I.KeyUp += new KeyEventHandler(tbResolveS2I_KeyUp);
tbResolveI2S.KeyUp += new KeyEventHandler(tbResolveI2S_KeyUp);
this.KeyPreview = true;
}
private void tbResolveS2I_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
btnResolveS2I_Click(sender, e);
e.SuppressKeyPress = true;
}
}
When I hit enter on my keyboard it sends both textboxes to do the same result. What i mean is if i hit enter on the first textbox it will act like I'm pressing enter on the other textbox aswell
If you want different events to perform the same thing you could add that code to a method and just call that method from the controls event method.
Also in the theme pack you are using, the button extends from Control and does not have a PerformClick() method.
example:
public Main() {
InitializeComponent();
KeyUp += new KeyEventHandler(Main_KeyUp);
this.KeyPreview = true;
}
private void Main_KeyUp(object sender, KeyEventArgs e) {
if(e.KeyCode == Keys.Enter) {
CustomCode();
e.SuppressKeyPress = true;
}
}
private void btnResolveS2I_Click(object sender, EventArgs e) {
CustomCode();
}
private void CustomCode() {
//Perform code here
}
}
I have a user control in window c# and i am adding that control into another project. I want to capture mouse click event which was clicked outside of the user control. How can i enable this feature in it?
You'll have to assign these,but this should work
bool ValidClick = false;
private void form_Click(object sender, EventArgs e)
{
if(!ValidClick)
ValidClick = true;
method();
}
private void control_Click(object sender, EventArgs e)
{
ValidClick = false;
method();
}
public void method()
{
if(ValidClick)
{
//Do method
}
}
In my User Control I have a Text Box which does the validation to take only digits. I place this user control on my form but the Keypress event is not Firing in form.Following is the code in my user control
protected override void OnKeyPress(KeyPressEventArgs e)
{
base.OnKeyPress(e);
if (this.KeyPress != null)
this.KeyPress(this, e);
}
private void txtLocl_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar!=(char)Keys.Back)
{
if (!char.IsDigit(e.KeyChar))
{
e.Handled = true;
}
}
}
but in Form also i want keypress event to fire but it is not firing
public Form1()
{
InitializeComponent();
txtNum.KeyPress += new KeyPressEventHandler(txtPrprCase1_KeyPress);
}
void txtPrprCase1_KeyPress(object sender, KeyPressEventArgs e)
{
MessageBox.Show("KeyPress is fired");
}
but it is not firing. I don't understand what i want to do? It is Urgent for me.
This following override is not needed:
protected override void OnKeyPress(KeyPressEventArgs e)
{
base.OnKeyPress(e);
if (this.KeyPress != null)
this.KeyPress(this, e);
}
Because base.OnKeyPress(e); will fire the attached event. You don't need to do it manually.
Instead call OnKeyPress of user control in the text-box's event handler:
private void txtLocl_KeyPress(object sender, KeyPressEventArgs e)
{
base.OnKeyPress(e);
if (e.KeyChar!=(char)Keys.Back)
{
if (!char.IsDigit(e.KeyChar))
{
e.Handled = true;
}
}
}
Try putting the event handler code in your Form_Load event, or using the Form Designer to create the event handler (it's in the lightning icon on the properties page).