Empty editText causing app to crash when trying to calculate

Question

I have an app with 4 EditText and one button that is supposed to calculate the inputs given

When one of those are left empty then the app crashes

How can I validate to throw an error when a EditText is left empty

Answer 1

You can use TextUtils.isEmpty(stringData) and it is preferred. For string.isEmpty() , a null string value will throw a NullPointerException .

TextUtils will always return a boolean value. In code, the former simply calls the equivalent of the other, plus a null check.

EditText myEditText1 = findViewById(R.id.editText1);
EditText myEditText2 = findViewById(R.id.editText2);
EditText myEditText3 = findViewById(R.id.editText3);
EditText myEditText4 = findViewById(R.id.editText4);

String myData1 = myEditText1.getText().toString();
String myData2 = myEditText2.getText().toString();
String myData3 = myEditText3.getText().toString();
String myData4 = myEditText4.getText().toString();

if(!TextUtils.isEmpty(myData1) && !TextUtils.isEmpty(myData2) && !TextUtils.isEmpty(myData3) && !TextUtils.isEmpty(myData4)) {
    //use edit text data
} else {
    Toast.makeText(this, "Fields value can not be empty",Toast.LENGTH_SHORT).show();
}

Answer 2

When you click the button check if the EditText is empty or not

Try below code

if(editText.getText().toString.length() == 0){
        // Display toast 
        Toast.makeText(getApplicationContext(), "Please enter something !",Toast.LENGTH_LONG).show();
}

Or you can use a library called AwesomeValiation

Answer 3

First you need to link the edit text and button with the id

EditText editText1 = findViewById(R.id.editText1);
EditText editText2 = findViewById(R.id.editText2);
EditText editText3 = findViewById(R.id.editText3);
EditText editText4 = findViewById(R.id.editText4);

Now you can get the value from the editText by using the below code

 String data = editText.getText();

For check the null value

if (data.isEmpty ){

Toast.makeText(getApplicationContext(),"the data is "+data,Toast.SHORT_LENGTH).show;

}