最容易理解的Android计算器实现

package com.example.Calcuator;
import com.wk.cal.CalAdd;
import com.wk.cal.CalDiv;
import com.wk.cal.CalMul;
import com.wk.cal.CalSub;
import com.wk.cal.Calculator;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class MyActivity extends Activity {
    TextView mtvText;
    Button mbtnAdd, mbtnSub, mbtnMul, mbtnDiv, mbtnResult, mbtnClear, mbtn0,
            mbtn1, mbtn2, mbtn3, mbtn4, mbtn5, mbtn6, mbtn7, mbtn8, mbtn9,mbtnExit;
    String num1, num2;
    String cal_Operator = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        initButton();
        AddButtonAction();
    }

    private void initButton() {
        mbtnClear = (Button) findViewById(R.id.btnClear);
        mtvText = (TextView) findViewById(R.id.tvResult);
        mbtnAdd = (Button) findViewById(R.id.btnAdd);
        mbtnSub = (Button) findViewById(R.id.btnSub);
        mbtnMul = (Button) findViewById(R.id.btnMul);
        mbtnDiv = (Button) findViewById(R.id.btnDiv);
        mbtnResult = (Button) findViewById(R.id.btnResult);
        mbtnExit    = (Button) findViewById(R.id.btnExit);
        mbtn0 = (Button) findViewById(R.id.btn0);
        mbtn1 = (Button) findViewById(R.id.btn1);
        mbtn2 = (Button) findViewById(R.id.btn2);
        mbtn3 = (Button) findViewById(R.id.btn3);
        mbtn4 = (Button) findViewById(R.id.btn4);
        mbtn5 = (Button) findViewById(R.id.btn5);
        mbtn6 = (Button) findViewById(R.id.btn6);
        mbtn7 = (Button) findViewById(R.id.btn7);
        mbtn8 = (Button) findViewById(R.id.btn8);
        mbtn9 = (Button) findViewById(R.id.btn9);

    }

    private void AddButtonAction() {
        mbtn0.setOnClickListener(new ButtonActionListener());
        mbtn1.setOnClickListener(new ButtonActionListener());
        mbtn2.setOnClickListener(new ButtonActionListener());
        mbtn3.setOnClickListener(new ButtonActionListener());
        mbtn4.setOnClickListener(new ButtonActionListener());
        mbtn5.setOnClickListener(new ButtonActionListener());
        mbtn6.setOnClickListener(new ButtonActionListener());
        mbtn7.setOnClickListener(new ButtonActionListener());
        mbtn8.setOnClickListener(new ButtonActionListener());
        mbtn9.setOnClickListener(new ButtonActionListener());
        mbtnAdd.setOnClickListener(new ButtonActionListener());
        mbtnSub.setOnClickListener(new ButtonActionListener());
        mbtnMul.setOnClickListener(new ButtonActionListener());
        mbtnDiv.setOnClickListener(new ButtonActionListener());
        mbtnResult.setOnClickListener(new ButtonActionListener());
        mbtnClear.setOnClickListener(new ButtonActionListener());
        mbtnExit.setOnClickListener(new ButtonActionListener());
    }

    class ButtonActionListener implements OnClickListener {
        public void btnClearAction(View v) {
            if (v.getId() == R.id.btnClear) {
                mtvText.setText("");

            }
        }

        public void btnAddAction(View v) {
            if (v.getId() == R.id.btnAdd) {
                num1 = (String) mtvText.getText();
                System.out.println("[num1]"+num1);
                mtvText.setText("");
                cal_Operator  = (String) mbtnAdd.getText();
            }
        }

        public void btnSubAction(View v) {
            if (v.getId() == R.id.btnSub) {
                num1 = (String) mtvText.getText();
                System.out.println("[num1]" + num1);
                mtvText.setText("");
                cal_Operator  = (String) mbtnSub.getText();
            }
        }

        public void btnMulAction(View v) {
            if (v.getId() == R.id.btnMul) {
                num1 = (String) mtvText.getText();
                System.out.println("[num1]"+num1);
                mtvText.setText("");
                cal_Operator  = (String) mbtnMul.getText();

            }
        }

        public void btnDivAction(View v) {
            if (v.getId() == R.id.btnDiv) {
                num1 = (String) mtvText.getText();
                System.out.println("[num1]"+num1);
                System.out.println(num1);
                mtvText.setText("");
                cal_Operator  = (String) mbtnDiv.getText();

            }
        }

        public void btn0Action(View v) {
            if (v.getId() == R.id.btn0) {
                mtvText.setText(mtvText.getText() + "0");
            }
        }

        public void btn1Action(View v) {
            if (v.getId() == R.id.btn1) {
                mtvText.setText(mtvText.getText() + "1");
            }
        }

        public void btn2Action(View v) {
            if (v.getId() == R.id.btn2) {
                mtvText.setText(mtvText.getText() + "2");
            }
        }

        public void btn3Action(View v) {
            if (v.getId() == R.id.btn3) {
                mtvText.setText(mtvText.getText() + "3");
            }
        }

        public void btn4Action(View v) {
            if (v.getId() == R.id.btn4) {
                mtvText.setText(mtvText.getText() + "4");
            }
        }

        public void btn5Action(View v) {
            if (v.getId() == R.id.btn5) {
                mtvText.setText(mtvText.getText() + "5");
            }
        }

        public void btn6Action(View v) {
            if (v.getId() == R.id.btn6) {
                mtvText.setText(mtvText.getText() + "6");
            }
        }

        public void btn7Action(View v) {
            if (v.getId() == R.id.btn7) {
                mtvText.setText(mtvText.getText() + "7");
            }
        }

        public void btn8Action(View v) {
            if (v.getId() == R.id.btn8) {
                mtvText.setText(mtvText.getText() + "8");
            }
        }

        public void btn9Action(View v) {
            if (v.getId() == R.id.btn9) {
                mtvText.setText(mtvText.getText() + "9");
            }
        }

        public void btnResultAction(View v) {
             try{
                 if(v.getId() ==  R.id.btnResult){
                     num2 = (String) mtvText.getText();
                     System.out.println("[num2]"+num2);
                     mtvText.setText("");
                     CalFactory factory = new CalFactory();
                     factory.createCalFactory(cal_Operator);
                 }
             }catch(Exception  e){
             }
        }

        public void btnExitAction(View v){
            if(v.getId() == R.id.btnExit){
                System.exit(0);
            }
        }

        @Override
        public void onClick(View v) {
            btnExitAction(v);
            btnClearAction(v);
            btn0Action(v);
            btn1Action(v);
            btn2Action(v);
            btn3Action(v);
            btn4Action(v);
            btn5Action(v);
            btn6Action(v);
            btn7Action(v);
            btn8Action(v);
            btn9Action(v);
            btnAddAction(v);
            btnSubAction(v);
            btnMulAction(v);
            btnDivAction(v);
            btnResultAction(v);

        }

    }

    class CalFactory {
        public void createCalFactory(String cal_Operator) {
            Calculator cal = null;
            switch (cal_Operator) {
                case "+":
                    cal = new CalAdd();
                    cal.setNum1(Double.valueOf(num1));
                    cal.setNum2(Double.valueOf(num2));
                    System.out.println("[num1]"+cal.getNum1()+"[num2]"+cal.getNum2());
                    mtvText.setText("加法"+num1+"[参数2]"+num2);
                    mtvText.setText(String.valueOf(cal.getResult()));
                    break;
                case "―":
                    cal = new CalSub();
                    cal.setNum1(Double.valueOf(num1));
                    cal.setNum2(Double.valueOf(num2));
                    mtvText.setText(String.valueOf(cal.getResult()));
                    break;
                case "×":
                    cal = new CalMul();
                    cal.setNum1(Double.valueOf(num1));
                    cal.setNum2(Double.valueOf(num2));
                    mtvText.setText(String.valueOf(cal.getResult()));
                    break;
                case "÷":
                    cal = new CalDiv();
                    cal.setNum1(Double.valueOf(num1));
                    cal.setNum2(Double.valueOf(num2));
                    mtvText.setText(String.valueOf(cal.getResult()));
                    break;
            }
        }
    }

}