Android can anyone tell me whats wrong with this? the if else doesn't give me what i want

So im making a converter. I'm having problems with the result which i named "dataValue". i think its my if-else statement but im not sure... i did the string.equals thing but im new to this stuff....

heres the code:

private void SetOnClickConvertButton(){
    Button convert = (Button) findViewById(R.id.buttonConvert);


    convert.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            EditText value = (EditText) findViewById(R.id.editTextValue);
            String dataValue = value.getText().toString();

            EditText unit = (EditText) findViewById(R.id.editTextUnits);
            String dataUnit = unit.getText().toString();

            EditText toUnit = (EditText) findViewById(R.id.editTextToUnits);
            String dataToUnit = unit.getText().toString();


            if(dataUnit.equals("Pound")){
                if(dataUnit.equals("Stone")){

                    double num=0;
                    num = 0.0714286 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Milligram")){

                    double num=0;
                    num = 453592 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Gram")){

                    double num=0;
                    num = 453.592 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);


                }if(toUnit.equals("Kilogram")){

                    double num=0;
                    num = 0.453592 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }

            }if(dataUnit.equals("Stone")){
                if(toUnit.equals("Pound")){

                    double num=0;
                    num = 14 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Milligram")){

                    double num=0;
                    num = 6350290 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Gram")){

                    double num=0;
                    num = 6350.29 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Kilogram")){

                    double num=0;
                    num = 6.35029 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }

            }if(dataUnit.equals("Milligram")){
                if(toUnit.equals("Pound")){

                    double num=0;
                    num = 0.0000022046 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Stone")){

                    double num=0;
                    num = 0.0000001575 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("gram")){

                    double num=0;
                    num = 0.001 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Kilogram")){

                    double num=0;
                    num =  0.000001 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }

            }if(dataUnit.equals("Gram")){
                if(toUnit.equals("Pound")){

                    double num=0;
                    num = 0.0022046226 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Stone")){

                    double num=0;
                    num = 0.000157473 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Milligram")){

                    double num=0;
                    num = 1000 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Kilogram")){

                    double num=0;
                    num = 1000000 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }

            }if(dataUnit.equals("Kilogram")){
                if(toUnit.equals("Pound")){

                    double num=0;
                    num = 2.2046226218 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Stone")){

                    double num=0;
                    num = 0.1574730444 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Milligram")){

                    double num=0;
                    num = 1000000 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }if(toUnit.equals("Gram")){

                    double num=0;
                    num = 1000 * (Double.parseDouble(dataValue));
                    dataValue = String.valueOf(num);

                }
            TextView DisplayValue = (TextView) findViewById(R.id.textViewAnswerValue);
            TextView DisplayUnit = (TextView) findViewById(R.id.textViewAnswerUnits);
            DisplayUnit.setText(dataToUnit);
            DisplayValue.setText(dataValue);
        }
    });

}

so guys what do you thing is wrong with the codes?