Grade Point Calculation Method in Android

private void calculateGradePoint() {
        String percentageStr = editTextPercentage.getText().toString();

        if (percentageStr.isEmpty()) {
            Toast.makeText(this, "Please enter a percentage.", Toast.LENGTH_SHORT).show();
            return;
        }

        try {
            double percentage = Double.parseDouble(percentageStr);

            if (percentage < 0 || percentage > 100) {
                textViewGradePoint.setText("Invalid input. Please enter a percentage between 0 and 100.");
                return;
            }

            double gradePoint;

            if (percentage >= 96) {
                gradePoint = 4.0;
            } else if (percentage >= 90) {
                gradePoint = 3.5;
            } else if (percentage >= 84) {
                gradePoint = 3.0;
            } else if (percentage >= 78) {
                gradePoint = 2.5;
            } else if (percentage >= 72) {
                gradePoint = 2.0;
            } else if (percentage >= 66) {
                gradePoint = 1.5;
            } else if (percentage >= 60) {
                gradePoint = 1.0;
            } else {
                gradePoint = 0;
            }

            textViewGradePoint.setText("Your grade point is: " + gradePoint);

        } catch (NumberFormatException e) {
            Toast.makeText(this, "Invalid input. Please enter a valid number.", Toast.LENGTH_SHORT).show();
        }
    }