Validation on EditText in alertDialog

Question

I am trying to add empty field validations on EditText on AlertDialog. But even after field is empty error message is not getting displayed, instea

Answer 1

This is how to validate input password inside AlertDialog.

Make sure you have created an individual xml layout file for the password which has only one component/view that is EditText to get the password from the user.

After creating a layout for input password, we will inflate the layout with Dialog as to set our custom view to the AlertDialog.

Inflater inflater = new Inflater(this);
View myPasswordView = inflater.inflate(R.xml.my_custom_password_layout);

AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
alertDialogBuilder.setTitle("Password");
//alertDialogBuilder.setMessage("Enter password to open Application.");
alertDialogBuilder.setView(myPasswordView);

alertDialogBuilder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which)
            {
                // Do not use this place as we are overriding this button later in the cade.
            }
        }); alertDialogBuilder.setPositiveButton("Cancel", 
        new DialogInterface.OnClickListener({
            @Override
            public void onClick(DialogInterface dialog, int which)
            {
                // Dismiss dialog and close activity if appropriated, do not use this (cancel) button at all. 
                dialog.dismiss();
            }
        });

final AlertDialog alertDialog = alertDialogBuilder.create();
alertDialog.show();
// Overriding the that button here immediatly handle the user's activity.
alertDialog.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(new View.OnClickListener()
      {            
          @Override
          public void onClick(View v)
          {
              Boolean isError = false;
              //Do your job here. For example we are checking the input password.
              final EditText txtPassword = myPasswordView.findViewById(R.id.txtPassword);
              String password = txtPassword.getText().toString().trim();
              Boolean isError = true;

              // Check password if not empty. You can add another IF statement to do your logic for password validation.
              if(password.isEmpty()) {
                  isError = true;
                  txtPassword.setError("Password cannot be empty");
              }
              if(password.equals("1234") {
                  // You password is correct. 
                  isError = false;
                  txtPassword.setError(null);
              }
              if(!isError)
                  dialog.dismiss();
              // Otherwise the dialog will stay open.
          }
      });