Why can't I use an int from a spinner in the same class?
Ok so I am working on an android app and I have implanted spinners... I have a total of four spinners and I have learned that if the spinner reads the options from the strings it has a defined number for the selection(i.e the first option is "0" next is "1" and so on)

I have the following code for the spinner

    		Spinner a = (Spinner) findViewById(R.id.spinner1);
		a.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

			@Override
			public void onItemSelected(AdapterView adapter, View v, int a,
					long lng) {
				// do something here
				Toast.makeText(adapter.getContext(), "You selected: " + a,
						Toast.LENGTH_SHORT).show();
			}

			@Override
			public void onNothingSelected(AdapterView arg0) {
				// do something else
			}
		});

and another one but with the int "b"

but later on in the same class I want to use some maths to get e=a,b (i.e if a=6 and b=5 e=65, or a=4 and b=3 e=43)
This is easily done by executing 

    int e=a*10+b;

The problem is I want to display this when you press a button, so I have the following code

	public void Calc(View v) {
		int e = a * 10 + b;
		Toast.makeText(this, "Value: " + e, Toast.LENGTH_LONG).show();
	}

but results in the error ""a" & "b" cannot be resolved to a variable"
why is this and how can I create a button that will be able to read these variables?
Why can't I use an int from a spinner in the same class?
===

Ok so I am working on an android app and I have implanted spinners... I have a total of four spinners and I have learned that if the spinner reads the options from the strings it has a defined number for the selection(i.e the first option is "0" next is "1" and so on)

I have the following code for the spinner

    		Spinner a = (Spinner) findViewById(R.id.spinner1);
		a.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

			@Override
			public void onItemSelected(AdapterView adapter, View v, int a,
					long lng) {
				// do something here
				Toast.makeText(adapter.getContext(), "You selected: " + a,
						Toast.LENGTH_SHORT).show();
			}

			@Override
			public void onNothingSelected(AdapterView arg0) {
				// do something else
			}
		});

and another one but with the int "b"

but later on in the same class I want to use some maths to get e=a,b (i.e if a=6 and b=5 e=65, or a=4 and b=3 e=43)
This is easily done by executing 

    int e=a*10+b;

The problem is I want to display this when you press a button, so I have the following code

	public void Calc(View v) {
		int e = a * 10 + b;
		Toast.makeText(this, "Value: " + e, Toast.LENGTH_LONG).show();
	}

but results in the error ""a" & "b" cannot be resolved to a variable"
why is this and how can I create a button that will be able to read these variables?