Changing TextInputLayout's Hint value as the user types in it

Question

Here is my TextInputEditText inside TextInputLayout. The hint you can see is set on TextInputLayout.

The user must write 255 characters otherwise the post is not valid.

I want the digit 255 to decrease as the user types and when reached to 0, the hint should be blank.

Here is my code :

private int charactersLeft = 256; is declared outside onCreate method.

And this code is inside onCreate method :

final TextInputLayout postTextInputBase = findViewById(R.id.post_text_input_base);

final TextInputEditText postTextInput = findViewById(R.id.post_text_input);

postTextInput.addTextChangedListener(new TextWatcher() {

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {

        if (charactersLeft == 0) {
            postTextInputBase.setHint(null);
        } else {
            postTextInputBase.setHint((charactersLeft - 1) + " characters left");
        }
    }

    @Override
    public void afterTextChanged(Editable s) {

    }
});

I also tried to set charactersLeft to characterLeft -= 1 but, the java won't allow me to do that.

Then, how do I do this ?

Answer 1

Use app:counterEnabled="true"

• Whether the character counter functionality is enabled or not in this layout.

Also use app:counterMaxLength="250"

• Sets the max length to display at the character counter.

Try this

<android.support.design.widget.TextInputLayout
    android:id="@+id/post_text_input_base"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:counterEnabled="true"
    app:counterMaxLength="250">

    <EditText
        android:id="@+id/post_text_input"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="UserName" />
</android.support.design.widget.TextInputLayout>

OUTPUT

EDIT

public class RecyclerViewActivity extends AppCompatActivity {

    TextInputLayout postTextInputBase;
    EditText postTextInputEditText;

    int textLength = 9;
    int len = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_recycler_view);

        postTextInputBase = findViewById(R.id.post_text_input_base);

        postTextInputEditText = findViewById(R.id.post_text_input);

        postTextInputBase.setHint(textLength + " characters left");

        postTextInputEditText.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

                // first check your EditText is empty or not
                if (!TextUtils.isEmpty(postTextInputEditText.getText().toString())) {

                    int len = postTextInputEditText.getText().toString().length();
                    // than check that editText text length is less than max length or not
                    // for test case i have set max length 10
                    if (len < 9) {
                        // if length of text is less than max length than use minus one from max length and set error in your text input layout
                        textLength--;
                    } else {
                        textLength++;
                        
                    }
                    
                    postTextInputBase.setHint(textLength + " characters left");
                } else {
                    textLength = 9;
                }
            }

            @Override
            public void afterTextChanged(Editable s) {

              if(postTextInputEditText.getText().toString().isEmpty()){
                  textLength = 9;
                  postTextInputBase.setHint(textLength + " characters left");
              }
            }
        });


    }


}

OUTPUT

EDIT 2 If you need set hint than use this

postTextInputBase.setHint(textLength + " characters left");

OUTPUT

NOTE Don't forgot to set android:maxLength="10" in edittext