实现加减乘除等简单计算的Android计算器源码包

package ymq.demo03; import android.app.Activity; import android.os.Bundle; import android.view.*; import android.widget.*; public class demo03 extends Activity { /** Called when the activity is first created. */ String str=""; EditText et; int c=0,flag=0; double b=0.0,g=0.0,f=0.0; View vi; public boolean onCreateOptionsMenu(Menu menu) { // TODO Auto-generated method stub menu.add(0, 1, 1, "退出"); return super.onCreateOptionsMenu(menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // TODO Auto-generated method stub if(item.getItemId()==1){finish();} return super.onOptionsItemSelected(item); } //计算方法 public double calculater(){ switch(c){ case 0:f=g;break; case 1:f=b+g;break; case 2:f=b-g;break; case 3:f=b*g;break; case 4:f=b/g;break; } b=f; c=0; return f; } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //获得按键 final Button number[]=new Button[10]; final Button fuhao[]=new Button[11]; fuhao[0]=(Button)findViewById(R.id.button01); fuhao[1]=(Button)findViewById(R.id.button02); fuhao[2]=(Button)findViewById(R.id.button03); fuhao[3]=(Button)findViewById(R.id.button04); fuhao[4]=(Button)findViewById(R.id.button05); fuhao[5]=(Button)findViewById(R.id.button06); fuhao[6]=(Button)findViewById(R.id.buttonce); fuhao[7]=(Button)findViewById(R.id.buttonc); fuhao[8]=(Button)findViewById(R.id.zheng); fuhao[9]=(Button)findViewById(R.id.kaifang); fuhao[10]=(Button)findViewById(R.id.pingfang); number[0]=(Button)findViewById(R.id.button0); number[1]=(Button)findViewById(R.id.button1); number[2]=(Button)findViewById(R.id.button2); number[3]=(Button)findViewById(R.id.button3); number[4]=(Button)findViewById(R.id.button4); number[5]=(Button)findViewById(R.id.button5); number[6]=(Button)findViewById(R.id.button6); number[7]=(Button)findViewById(R.id.button7); number[8]=(Button)findViewById(R.id.button8); number[9]=(Button)findViewById(R.id.button9); et=(EditText) findViewById(R.id.textView1); et.setText(str); fuhao[6].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub str=""; et.setText(str); vi=v; } }); fuhao[7].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub b=0.0;c=0;g=0.0; str=""; et.setText(str); } }); fuhao[8].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(vi!=fuhao[5]&&str;!=""){ char ch=str.charAt(0); if(ch=='-') str=str.replace("-",""); else str="-"+str; et.setText(str); } } }); fuhao[9].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""){ double a=Double.parseDouble(str); str=Math.sqrt(a)+""; et.setText(str); }} }); fuhao[10].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""){ double a=Double.parseDouble(str); str=""+a*a; et.setText(str); }} }); //设定数字按键 number[0].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=0; et.setText(str); flag=0; } else{ char ch1[]; ch1=str.toCharArray(); if(!(ch1.length==1&&ch1;[0]=='0')) {str+=0; et.setText(str);} } vi=v; } }); number[1].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=1; et.setText(str); flag=0; } else{ str+=1; et.setText(str); } vi=v; } }); number[2].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=2; et.setText(str); flag=0; } else{ str+=2; et.setText(str); } vi=v; } }); number[3].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=3; et.setText(str); flag=0; } else{ str+=3; et.setText(str); } vi=v; } }); number[4].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=4; et.setText(str); flag=0; } else{ str+=4; et.setText(str); } vi=v; } }); number[5].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=5; et.setText(str); flag=0; } else{ str+=5; et.setText(str); } vi=v; } }); number[6].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=6; et.setText(str); flag=0; } else{ str+=6; et.setText(str); } vi=v; } }); number[7].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=7; et.setText(str); flag=0; } else{ str+=7; et.setText(str); } vi=v; } }); number[8].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=8; et.setText(str); flag=0; } else{ str+=8; et.setText(str); } vi=v; } }); number[9].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(flag==1){ str=""; str+=9; et.setText(str); flag=0; } else{ str+=9; et.setText(str); } vi=v; } }); //设定符号键 //加 fuhao[0].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""){ if(vi==fuhao[0]||vi==fuhao[1]||vi==fuhao[2]||vi==fuhao[3]){ c=1; } else{ g=Double.parseDouble(str); calculater(); str=""+f; et.setText(str); c=1; flag=1; vi=v; }} } }); //减 fuhao[1].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""){ if(vi==fuhao[0]||vi==fuhao[1]||vi==fuhao[2]||vi==fuhao[3]){ c=2; } else{ g=Double.parseDouble(str); calculater(); str=""+f; et.setText(str); c=2; flag=1; vi=v; }} } }); //乘 fuhao[2].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""){ if(vi==fuhao[0]||vi==fuhao[1]||vi==fuhao[2]||vi==fuhao[3]){ c=3; } else{ g=Double.parseDouble(str); calculater(); str=""+f; et.setText(str); c=3; flag=1; vi=v; }} } }); //除 fuhao[3].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""){ if(vi==fuhao[0]||vi==fuhao[1]||vi==fuhao[2]||vi==fuhao[3]){ c=4; } else{ g=Double.parseDouble(str); calculater(); str=""+f; et.setText(str); c=4; flag=1; vi=v; }} } }); //等号 fuhao[4].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str!=""&&vi;!=fuhao[0]&&vi;!=fuhao[1]&&vi;!=fuhao[2]&&vi;!=fuhao[3]){ g=Double.parseDouble(str); calculater(); str=""+f; et.setText(str); flag=1; vi=v; } } }); //小数点 fuhao[5].setOnClickListener(new View.OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub if(str==""){ str+="."; et.setText(str); } else{ char ch1[];int x=0; ch1=str.toCharArray(); for(int i=0;i<ch1.length;i++) if(ch1[i]=='.') x++; if(x==0){ str+="."; et.setText(str); } } } }); } }