Casting String to Integer not working, throwing NumberFormatException

The value of walletBalance is a string, eg "150.0".

I am trying to display an error message in form of a toast in another activity(SuccessActivity) is the amount to be withdrawn from the user is less than the wallet balance. I keep getting NumberFormatException error for the value of i, so i decided to use a try catch block but it still doesnt work. Here is the method below.

 private void checkWalletBalance(int amount, Context context){
        String walletBalance = Preferences.getBalance(context);

                try {
            int i = Integer.parseInt(walletBalance.trim());
                    if(amount < i){
                        Intent intent = new Intent(getBaseContext(), SuccessActivity.class);
                        startActivity(intent);
                      
                        Toast. makeText(ActivityHome.this,"Insufficient Wallet Balance",Toast. LENGTH_LONG).show();
                    }
        }
        catch (NumberFormatException nfe){
            System.out.println("NumberFormatException: " + nfe.getMessage());

        }


    }

Alos, I want to display a toast in the success Activity, If the condition i true. here is the code in success activity to display the toast message.

    private void insufficientError(){
        Intent intent = getIntent();
        intent.getExtras();
        
        Toast.makeText(SuccessActivity.this,"Insufficient  Balance",Toast.LENGTH_LONG).show();
        
    }

Like @Blackbelt commented, you are trying to parse a double string and not an integer.

Therefore, you need to do the following:

double amount = Double.parseDouble(walletBalance.trim());

You could use either of the following-

Double.valueOf(walletBalance.trim());
Double.parseDouble(walletBalance.trim());

And then if you want to convert them to Integer/int like this -

Integer i = Double.valueOf(walletBalance.trim()).intValue();
int i = (int) Double.parseDouble(walletBalance.trim());

NumberFormatException - Thrown to indicate that the application has attempted to convert a string to one of the numeric types, but that the string does not have the appropriate format.

Don't

 int i = Integer.parseInt(walletBalance.trim());  //walletBalance.trim() ==150.0

Do

   int i = (int) Double.parseDouble(walletBalance.trim());