I have a custom edittext control which has a clear (x) icon set on the right when it's in focus and has text. Clicking the clear icon removes the text from the textbox. Unfortunately, when you click into the textbox, the focus change event is fired infinitely, as changing the compound drawable within the focus change listener seems to fire off two more focus change events, the first with the focus off, and the second with the focus back on. Any idea how I can get this working without the infinite loop?
Here is the code:
public class CustomEditText : EditText {
private Drawable clearButton;
protected CustomEditText (IntPtr javaReference, JniHandleOwnership transfer) : base (javaReference, transfer) {
}
public CustomEditText (Context context) : base (context) {
Init ();
}
public CustomEditText (Context context, IAttributeSet attrs) : base (context, attrs) {
Init (attrs);
}
public CustomEditText (Context context, IAttributeSet attrs, int defStyle) : base (context, attrs, defStyle) {
Init (attrs);
}
protected void Init (IAttributeSet attrs = null) {
// Set up clear button
SetupClearButton ();
SetupEvents ();
}
private void SetupClearButton () {
clearButton = ContextCompat.GetDrawable (Android.App.Application.Context, Resource.Drawable.forms_edit_text_clear_gray);
clearButton.SetBounds (0, 0, clearButton.IntrinsicWidth, clearButton.IntrinsicHeight);
}
private void SetupEvents () {
// Handle clear button visibility
this.TextChanged += (sender, e) => {
if (this.HasFocus)
UpdateClearButton ();
};
this.FocusChange += (object sender, FocusChangeEventArgs e) => {
UpdateClearButton (e.HasFocus);// Gets called infinitely
};
// Handle clearing the text
this.Touch += (sender, e) => {
if (this.GetCompoundDrawables ()[2] != null &&
e.Event.Action == MotionEventActions.Up &&
e.Event.GetX () > (this.Width - this.PaddingRight - clearButton.IntrinsicWidth)) {
this.Text = "";
UpdateClearButton ();
e.Handled = true;
} else
e.Handled = false;
};
}
private void UpdateClearButton (bool hasFocus = true) {
var compoundDrawables = this.GetCompoundDrawables ();
var compoundDrawable = this.Text.Length == 0 || !hasFocus ? null : clearButton;
if (compoundDrawables[2] != compoundDrawable)
this.SetCompoundDrawables (compoundDrawables[0], compoundDrawables[1], compoundDrawable, compoundDrawables[3]);
}
}