Events and Interactivity in Xamarin Numeric Entry (SfNumericTextBox)

19 May 20212 minutes to read

Events

ValueChanged

We can perform operation while the changing the value of NumericTextBox’s Value using ValueChanged event. ValueChanged event returns the changed value in NumericTextBox.

Members	Description
Value	Displays changed value in NumericTextBox

xaml
c#
<syncfusion:SfNumericTextBox x:Name="numericTextBox" ValueChanged="Handle_ValueChanged" Value="123"  />
SfNumericTextBox numericTextBox=new SfNumericTextBox();
numericTextBox.Value = 123;
numericTextBox.ValueChanged += Handle_ValueChanged;
this.Content=numericTextBox;

void Handle_ValueChanged(object sender, Syncfusion.SfNumericTextBox.XForms.ValueEventArgs e)
{
    System.Diagnostics.Debug.WriteLine(e.Value.ToString());
}

Interactivity : ValueChangeMode

The ValueChangeMode property is used to mention when the validation need to take place, either in key pressed or in focus lost. When ValueChangeMode is set to OnKeyFocus, the validation will be carried out for each key press. When ValueChangeMode is OnLostFocus, the validation occur when the control lost the focus or the focus move to next control. ValueChangeMode includes the following options:

OnKeyFocus
OnLostFocus

OnKeyFocus

xaml
c#
<syncfusion:SfNumericTextBox ValueChangeMode="OnKeyFocus" x:Name="numericTextBox"  Value="123"  />
SfNumericTextBox numericTextBox=new SfNumericTextBox();
numericTextBox.Value = 123;
numericTextBox.ValueChangeMode = ValueChangeMode.OnKeyFocus;
this.Content=numericTextBox;

Display SfNumericTextBox control with ValueChanged event OnKeyFocus

OnLostFocus

xaml
c#
<syncfusion:SfNumericTextBox ValueChangeMode="OnLostFocus" x:Name="numericTextBox"  Value="123"  />
SfNumericTextBox numericTextBox=new SfNumericTextBox();
numericTextBox.Value = 123;
numericTextBox.ValueChangeMode = ValueChangeMode.OnLostFocus;
this.Content=numericTextBox;

Display SfNumericTextBox control with ValueChanged event OnLostFocus

Completed

Raised when the user finalizes the text in the NumericTextBox by pressing return key on the keyboard.

xaml
c#
<syncfusion:SfNumericTextBox x:Name="numericTextBox" Completed="Handle_Completed”/>
SfNumericTextBox numericTextBox=new SfNumericTextBox();
numericTextBox.Completed += Handle_Completed;
this.Content=numericTextBox;

void Handle_Completed(object sender, System.EventArgs e)
{
  System.Diagnostics.Debug.WriteLine(“Completed”);         
}