I am using AutoCompleteTextView, when the user clicks on it, I want to show suggestions even if it has no text - but setThreshold(0) works exactly
Destil's answer above almost works, but has one subtle bug. When the user first gives focus to the field it works, however if they leave and then return to the field it will not show the drop down because the value of mPopupCanBeUpdated will still be false from when it was hidden. The fix is to change the onFocusChanged method to:
@Override
protected void onFocusChanged(boolean focused, int direction,
Rect previouslyFocusedRect) {
super.onFocusChanged(focused, direction, previouslyFocusedRect);
if (focused) {
if (getText().toString().length() == 0) {
// We want to trigger the drop down, replace the text.
setText("");
}
}
}