In Android, how to make Login button disable with respect to EditText?

Question

If EditText is empty then Login Button has to be disabled. And if EditText has some texts then Login Button has to be ena

Answer 1

You need to track user's action inside EditText using TextWatcher object:

myEditText.addTextChangedListener(new TextWatcher()
        {

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

            }

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

            }

            @Override
            public void afterTextChanged(Editable s)
            {
                if (s.length() > 1)
                {
                    //enable button
                } else
                    //disable
            }
        });

Answer 2

heres what you are looking for :

private EditText et1,et2;
//  create a textWatcher member
private TextWatcher mTextWatcher = new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence charSequence, int i, int i2, int i3) {
    }

    @Override
    public void onTextChanged(CharSequence charSequence, int i, int i2, int i3) {
    }

    @Override
    public void afterTextChanged(Editable editable) {
        // check Fields For Empty Values
        checkFieldsForEmptyValues();
    }
};

void checkFieldsForEmptyValues(){
    Button b = (Button) findViewById(R.id.button1);

    String s1 = et1.getText().toString();
    String s2 = et2.getText().toString();

    if(s1.equals("")|| s2.equals("")){
        b.setEnabled(false);
    } else {
        b.setEnabled(true);
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login_check);
    et1 = (EditText) findViewById(R.id.editText1);
    et2 = (EditText) findViewById(R.id.editText2);


    // set listeners
    et1.addTextChangedListener(mTextWatcher);
    et2.addTextChangedListener(mTextWatcher);

    // run once to disable if empty
    checkFieldsForEmptyValues(); 
}

Answer 3

hey if want to use the code cut the button needs to change color if the editText1_id and the editText1_passcode is in and in 4 digits

checkValidation();

    editText1_id.addTextChangedListener(mWatcher);
    editText1_passcode.addTextChangedListener(mWatcher);
}

private void checkValidation() {
    // TODO Auto-generated method stub

    if ((TextUtils.isEmpty(editText1_id.getText()))
            || (TextUtils.isEmpty(editText1_passcode.getText())))
        loginbtn.setEnabled(false);
    else
        loginbtn.setEnabled(true);

}


TextWatcher mWatcher = new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence s, int start, int before,
                              int count) {
        // TODO Auto-generated method stub
        checkValidation();
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count,
                                  int after) {
        // TODO Auto-generated method stub

    }

    @Override
    public void afterTextChanged(Editable s) {
        // TODO Auto-generated method stub

    }
};

}