Android: On EditText Changed Listener

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Android: On EditText Changed Listener

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In my project I have a EditText. I want to show how many characters are there in the EditText and show it in the TextView. I have written following code and it works fine. However, my problem is when I click Backspace it counts up. I need to decrement the number. What should I do? How can I take Backspace Key?

    tv = (TextView)findViewById(R.id.charCounts);    textMessage = (EditText)findViewById(R.id.textMessage);    textMessage.addTextChangedListener(new TextWatcher(){        public void afterTextChanged(Editable s) {            i++;            tv.setText(String.valueOf(i) + " / " + String.valueOf(charCounts));        }        public void beforeTextChanged(CharSequence s, int start, int count, int after){}        public void onTextChanged(CharSequence s, int start, int before, int count){}    });

public interface

TextWatcher

implements NoCopySpan

android.text.TextWatcher

Known Indirect Subclasses

AbsListView, ExpandableListView, GridView, ListView, PasswordTransformationMethod, PhoneNumberFormattingTextWatcher

Class Overview

When an object of a type is attached to an Editable, its methods will be called when the text is changed.

Summary

Public Methodsabstract voidafterTextChanged(Editable s)

This method is called to notify you that, somewhere within s, the text has been changed.

abstract voidbeforeTextChanged(CharSequence s, int start, int count, int after)

This method is called to notify you that, within s, the count characters beginning at start are about to be replaced by new text with length after.

abstract voidonTextChanged(CharSequence s, int start, int before, int count)

This method is called to notify you that, within s, the count characters beginning at start have just replaced old text that had length before.

Public Methods

public abstract void afterTextChanged (Editable s)

Added in API level 1

This method is called to notify you that, somewhere within s, the text has been changed. It is legitimate to make further changes to s from this callback, but be careful not to get yourself into an infinite loop, because any changes you make will cause this method to be called again recursively. (You are not told where the change took place because other afterTextChanged() methods may already have made other changes and invalidated the offsets. But if you need to know here, you can use setSpan(Object, int, int, int) in onTextChanged(CharSequence, int, int, int) to mark your place and then look up from here where the span ended up.

public abstract void beforeTextChanged (CharSequence s, int start, int count, int after)

Added in API level 1

This method is called to notify you that, within s, the count characters beginning at start are about to be replaced by new text with length after. It is an error to attempt to make changes to s from this callback.

public abstract void onTextChanged (CharSequence s, int start, int before, int count)

Added in API level 1

This method is called to notify you that, within s, the count characters beginning at start have just replaced old text that had length before. It is an error to attempt to make changes to s from this callback.