I created an InputFilter for an EditText component that only allows doubles within a range (e.g. from 1.5 to 5.5). Everything worked fine until I deleted the decimal point:
I typed 1.68 and then deleted the decimal point. The value in the text field became 168, which is obviously outside the range.
Here is a simplified version of my filter
public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
if (isValid(dest.toString() + source.toString())) {
//input is valid
return null;
}else{
//The input is not valid
return "";
}
}
private boolean isValid(String input) {
Double inputValue = Double.parseDouble(input);
boolean isMinValid = (1.5 <= inputValue);
boolean isMaxValid = (5.5 >= inputValue);
return isMinValid && isMaxValid;
}
I solved my problem. Here is the solution in case someone else needs it:
public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
if (isValid(dest.toString() + source.toString())) {
//input is valid
return null;
}else{
//The input is not valid
if (source.equals("") && dest.toString().length() != 1) {
//backspace was clicked, do not accept that change,
//unless user is deleting the last char
CharSequence deletedCharacter = dest.subSequence(dstart, dend);
return deletedCharacter;
}
return "";
}
}