简易计算器

package com.hanqi.jisuanqi;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    Button a1;
    Button a2;
    Button a3;
    Button a4;
    Button a5;
    Button a6;
    Button a7;
    Button a8;
    Button a9;
    Button a0;
    Button xiao;
    Button gui;
    Button b1;
    Button b2;
    Button b3;
    Button b4;
    Button b5;
    Button dian;
    TextView et;
    //str==null !=str.length()==0
    //s6为何无效
    //s1存储数据
    double s1 = 0;
    //判断运算
    int s2 = 0;
    //承载连续运算数字
    double s3 = 0;
    //显示结果
    double s4;
    //运算完成后使用结果直接下次运算
    int s5=0;
    //确认小数点输入一次
    int s6=0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.jisuan);
        et = (TextView) findViewById(R.id.wenjian);
        a1 = (Button) findViewById(R.id.aa1);
        a2 = (Button) findViewById(R.id.aa2);
        a3 = (Button) findViewById(R.id.a3);
        a4 = (Button) findViewById(R.id.a4);
        a5 = (Button) findViewById(R.id.a5);
        a6 = (Button) findViewById(R.id.a6);
        a7 = (Button) findViewById(R.id.a7);
        a8 = (Button) findViewById(R.id.a8);
        a9 = (Button) findViewById(R.id.a9);
        a0 = (Button) findViewById(R.id.a0);
        b1 = (Button) findViewById(R.id.jia);
        b2 = (Button) findViewById(R.id.jian);
        b3 = (Button) findViewById(R.id.cheng);
        b4 = (Button) findViewById(R.id.chu);
        b5 = (Button) findViewById(R.id.deng);
        xiao = (Button) findViewById(R.id.xiao);
        gui = (Button) findViewById(R.id.gui);
        dian = (Button) findViewById(R.id.dian);

        a1.setOnClickListener(new shuzi());
        a2.setOnClickListener(shu);
        a3.setOnClickListener(shu);
        a4.setOnClickListener(shu);
        a5.setOnClickListener(shu);
        a6.setOnClickListener(shu);
        a7.setOnClickListener(shu);
        a8.setOnClickListener(shu);
        a9.setOnClickListener(shu);
        a0.setOnClickListener(shu);
        b1.setOnClickListener(jia1);
        b2.setOnClickListener(jian1);
        b3.setOnClickListener(cheng1);
        b4.setOnClickListener(chu1);
        b5.setOnClickListener(deng1);
        dian.setOnClickListener(dian1);
        xiao.setOnClickListener(xiao1);
        gui.setOnClickListener(gui1);

    }

    shuzi shu = new shuzi();
     jia jia1=new jia();
    jian jian1=new jian();
    cheng cheng1=new cheng();
    chu chu1=new chu();
    deng deng1=new deng();
    xiao xiao1=new xiao();
    gui gui1=new gui();
    dian dian1=new dian();



    class shuzi implements View.OnClickListener {
        public void onClick(View v) {
            if (s5 == 1) {
                et.setText(null);
                s1 = 0;
                s2 = 0;
                s3 = 0;
                s4 = 0;
                s5 = 0;
            }
            Button b = (Button) v;
            String str = et.getText().toString();
            String str2 = b.getText().toString();
            str += str2;
            et.setText(str);
        }
    }

    class dian implements View.OnClickListener {
            public void onClick(View v) {
                if(s5==1){et.setText(null);
                    s1=0;
                    s2=0;
                    s3=0;
                    s4=0;
                    s5=0;}

                if(s6==1){
                    Toast.makeText(MainActivity.this, "好好输入", Toast.LENGTH_SHORT).show();
                    return;}
                Button b = (Button) v;
                String str = et.getText().toString();

                if(str.length()==0||str.equals("0.")){
                    et.setText("0.");
                    Toast.makeText(MainActivity.this, "111", Toast.LENGTH_SHORT).show();
                    return;
                }

                String str2 = b.getText().toString();
                str += str2;
                et.setText(str);
                s6=1;
            }
        }

    class jia implements View.OnClickListener {
        public void onClick(View v) {
            s5=0;
            Button b = (Button) v;
            String str = et.getText().toString();
            if (str.length()==0) {
                return;
            }
            if (s1 == 0) {
                s1 = Double.parseDouble(str);

            } else {
                s3 = Double.parseDouble(str);


                if (s2 == 0) {
                    s1 = s3;
                }
                if (s2 == 1) {
                    s1 += s3;
                }
                if (s2 == 2) {
                    s1 -= s3;
                }
                if (s2 == 3) {
                    s1 *= s3;
                }
                if (s2==4&&s3!=0) {
                    s1 /= s3;
                }
                if (s2==4&&s3==0) {
                    Toast.makeText(MainActivity.this, "全部清除重新输入", Toast.LENGTH_SHORT).show();
                    s1=0;
                    s2=0;
                    s3=0;
                    s4=0;
                    s5=0;
                }
            }
                et.setText(null);
                 s2 = 1;
            s6=0;
            Toast.makeText(MainActivity.this, ("s1="+s1+" s2="+s2+" s3="+s3), Toast.LENGTH_SHORT).show();
        }
    }

    class jian implements View.OnClickListener {
            public void onClick(View v) {
                s5=0;
                Button b = (Button) v;
                String str = et.getText().toString();
                if (str.length()==0) {
                    return;
                }
                if (s1 == 0) {
                    s1 =Double.parseDouble(str);

                } else {
                    s3 = Double.parseDouble(str);
                    if(s2==0){s1=s3;}
                    if(s2==1){s1+=s3;}
                    if(s2==2){s1-=s3;}
                    if(s2==3){s1*=s3;}
                    if(s2==4&&s3!=0){s1/=s3;}
                    if (s2==4&&s3==0) {
                        Toast.makeText(MainActivity.this, "全部清除重新输入", Toast.LENGTH_SHORT).show();
                        s1=0;
                        s2=0;
                        s3=0;
                        s4=0;
                        s5=0;
                    }
                }
                s2 = 2;
                s6=0;
                et.setText(null);
                Toast.makeText(MainActivity.this, ("s1="+s1+" s2="+s2+" s3="+s3), Toast.LENGTH_SHORT).show();

            }
        }

    class cheng implements View.OnClickListener {
            public void onClick(View v) {
                s5=0;
                Button b = (Button) v;
                String str = et.getText().toString();
                if (str.length()==0) {
                    return;
                }
                if (s1 == 0) {
                    s1 = Double.parseDouble(str);

                } else {
                    s3 = Double.parseDouble(str);
                    if(s2==0){s1=s3;}
                    if(s2==1){s1+=s3;}
                    if(s2==2){s1-=s3;}
                    if(s2==3){s1*=s3;}
                    if(s2==4&&s3!=0){s1/=s3;}
                    if (s2==4&&s3==0) {
                        Toast.makeText(MainActivity.this, "全部清除重新输入", Toast.LENGTH_SHORT).show();
                        s1=0;
                        s2=0;
                        s3=0;
                        s4=0;
                        s5=0;
                    }
                }
                s2 = 3;
                s6=0;
                et.setText(null);
                Toast.makeText(MainActivity.this, ("s1="+s1+" s2="+s2+" s3="+s3), Toast.LENGTH_SHORT).show();

            }
        }

    class chu implements View.OnClickListener {
            public void onClick(View v) {
                s5=0;
                Button b = (Button) v;
                String str = et.getText().toString();
                if (str.length()==0) {
                    return;
                }

                if (s1 == 0) {
                    s1 = Double.parseDouble(str);

                } else {

                    s3 = Double.parseDouble(str);
                    if(s2==0){s1=s3;}
                    if(s2==1){s1+=s3;}
                    if(s2==2){s1-=s3;}
                    if(s2==3){s1*=s3;}
                    if(s2==4&&s3!=0){s1/=s3;}
                    if (s2==4&&s3==0) {
                        Toast.makeText(MainActivity.this, "全部清除重新输入", Toast.LENGTH_SHORT).show();
                        s1=0;
                        s2=0;
                        s3=0;
                        s4=0;
                        s5=0;
                    }
                }
                s2 = 4;
                s6=0;
                et.setText(null);
                Toast.makeText(MainActivity.this, ("s1="+s1+" s2="+s2+" s3="+s3), Toast.LENGTH_SHORT).show();
            }
        }

    class deng implements View.OnClickListener {
            public void onClick(View v) {
                String str = et.getText().toString();
                if(str.length()==0){return;}
                s3 = Double.parseDouble(str);
                if(s3==0&&s2==4){
                    Toast.makeText(MainActivity.this, "逗逼", Toast.LENGTH_SHORT).show();
                    return;
                }
                if(s2==0){s4=s3;}
                if(s2==1){s4=s1+s3;}
                if(s2==2){s4=s1-s3;}
                if(s2==3){s4=s1*s3;}
                if(s2==4&&s3!=0){s4=s1/s3;}
                if (s2==4&&s3==0) {
                    Toast.makeText(MainActivity.this, "全部清除重新输入", Toast.LENGTH_SHORT).show();
                    s1=0;
                    s2=0;
                    s3=0;
                    s4=0;
                    s5=0;
                }
                String str2=s4+"";
                et.setText(str2);
                s5=1;
                s2=0;
                s6=0;
                Toast.makeText(MainActivity.this, ("s1="+s1+" s2="+s2+" s3="+s3), Toast.LENGTH_SHORT).show();

            }
        }

    class gui implements View.OnClickListener {
        public void onClick(View v) {
            s1=0;
            s2=0;
            s3=0;
            s5=0;
            s4=0;
            s6=0;
            et.setText(null);
        }
    }

    class xiao implements View.OnClickListener {
        public void onClick(View v) {

            String str=et.getText().toString();
            if(str.length()==0){
                return;
            }
            String str2=str.substring(0,str.length()-1);
            et.setText(str2);
            if(s5==1){
                s5=0;
            }
        }
    }
    }

<?xml version="1.0" encoding="utf-8"?>
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:rowCount="6"
    android:columnCount="4">
    <TextView

        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_columnSpan="4"
        android:layout_rowWeight="15"
        android:hint="0"
        android:gravity="bottom|right"
        android:textSize="30dp"
        android:id="@+id/wenjian"

        />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="C"
        android:textSize="30dp"
        android:id="@+id/xiao"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="◀"
        android:textSize="30dp"
        android:id="@+id/gui"
        />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="÷"
        android:textSize="30dp"
        android:id="@+id/chu"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="×"
        android:textSize="30dp"
        android:id="@+id/cheng"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="1"
        android:textSize="30dp"
        android:id="@+id/aa1"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="2"
        android:textSize="30dp"
        android:id="@+id/aa2"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="3"
        android:textSize="30dp"
        android:id="@+id/a3"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="－"
        android:textSize="30dp"
        android:id="@+id/jian"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="4"
        android:textSize="30dp"
        android:id="@+id/a4"
        />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="5"
        android:textSize="30dp"
        android:id="@+id/a5"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="6"
        android:textSize="30dp"
        android:id="@+id/a6"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="+"
        android:textSize="30dp"
        android:id="@+id/jia"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="7"
        android:textSize="30dp"
        android:id="@+id/a7"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="8"
        android:textSize="30dp"
        android:id="@+id/a8"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="9"
        android:textSize="30dp"
        android:id="@+id/a9"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:layout_rowSpan="2"
        android:text="="
        android:textSize="30dp"
        android:id="@+id/deng"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:layout_columnSpan="2"
        android:text="0"
        android:textSize="30dp"
        android:id="@+id/a0"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_rowWeight="1"
        android:layout_columnWeight="1"
        android:text="."
        android:textSize="30dp"
        android:id="@+id/dian"/>


</GridLayout>