Question

My layout is:

1 EditText (id = etvalue1)
1 EditText (id = etvalue2)
1 Button (id = save)

I need to know how to do the following with these widgets:

• If the User clicks on the button with the EditText empty display a message and wait for the User to enter the value.
• Display the message until the User and enter the value after the value is to enter the calculation (etvalue1 + etvalue2) and show the result.

Answer 1

In onclicklistener for the button do the following

if(edit1.getText().equals("") || edit2.getText().equals(""))  
{
     //toast the error message 
     return;
}
 //calculate the result

The maximum time for toast is Toast.LENGTH_LONG. If you want the message to be displayed till the user enters data in edittext, then use a textview to display the message. Set onTextChangedListener on both the EditTexts to check if the text is changed. in afterTextChanged method you can do the calculation.