Android 操作系統(tǒng)概述計算器的實現(xiàn)實驗報告

1、信息學院實驗報告學號：I姓名：I班級：一課程名稱：Android操作系次概述|實驗名稱：計算器而實現(xiàn)一實驗性質：驗證性實驗實驗時間：2016年4月20| 實驗地點：睿智4-212.實驗目的用eclipse實現(xiàn)計算器。驗證 1/3+1/3+1/3=1 和 0.001+0.0011=0.0021 。.實驗內容及環(huán)境設備內容：實現(xiàn)計算器，并驗證 1/3+1/3+1/3=1 和 0.001+0.0011=0.0021 。設備：eclipse 軟件。.實驗步驟3.1、流程圖開始XML 布局和 MainActivity.java 代碼、在activity_main.xml文件中寫好布局。以其中一行為例，其

2、代碼如下：/線性布局/、 布局寫好后，在 MainActivity. java 頁中實例化 activity_main.xml中的按鈕和TextView ,其代碼如下：package com.candy.ll;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 Mai

3、nActivity extends Activity implements OnClickListener /聲明一些控件Button btn0=null;Button btn1=null;Button btn2=null;Button btn3=null;Button btn4=null;Button btn5=null;Button btn6=null;Button btn7=null;Button btn8=null;Button btn9=null;Button btnBackspace=null;Button btnCE=null;Button btnAdd=null;Button

4、btnSub=null;Button btnMul=null;Button btnDiv=null;Button btnEqu=null;TextView tvResult=null;/聲明兩個參數(shù)，接收 tvResult前后的值double num1=0,num2=0;double Result=0;/ 計算結果int op=0;int a=0;/判斷操作數(shù)boolean isClickEqu=false;/判斷是否按下=Overrideprotected void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanc

5、eState);setContentView(R.layout.counter);/從布局文件中獲取控件btn0=(Button)findViewById(R.id.btn0);btn1=(Button)findViewById(R.id.btn1);btn2=(Button)findViewById(R.id.btn2);btn3=(Button)findViewById(R.id.btn3);btn4=(Button)findViewById(R.id.btn4);btn5=(Button)findViewById(R.id.btn5);btn6=(Button)findViewById(

6、R.id.btn6);btn7=(Button)findViewById(R.id.btn7);btn8=(Button)findViewById(R.id.btn8);btn9=(Button)findViewById(R.id.btn9);btnBackspace=(Button)findViewById(R.id.btnBackspace);btnCE=(Button)findViewById(R.id.btnCE);btnEqu=(Button)findViewById(R.id.btnEqu);btnAdd=(Button)findViewById(R.id.btnAdd);btnS

7、ub=(Button)findViewById(R.id.btnSub); btnMul=(Button)findViewById(R.id.btnMul); btnDiv=(Button)findViewById(R.id.btnDiv); tvResult=(TextView)findViewById(R.id.tvRestult); /添加監(jiān)聽 btnBackspace.setOnClickListener(this); btnCE.setOnClickListener(this); btnO.setOnClickListener(this); btnl.setOnClickListen

8、er(this); btn2.setOnClickListener(this); btn3.setOnClickListener(this); btn4.setOnClickListener(this); btn5.setOnClickListener(this); btn6.setOnClickListener(this); btn7.setOnClickListener(this); btn8.setOnClickListener(this);btn9.setOnClickListener(this); btnAdd.setOnClickListener(this); btnSub.set

9、OnClickListener(this); btnMul.setOnClickListener(this); btnDiv.setOnClickListener(this); btnEqu.setOnClickListener(this); Override public void onClick(View v) / TODO Auto-generated method stub switch(v.getId() /btnBackspace 和 CEcase R.id.btnBackspace:String myStr=tvResult.getText().toString(); trytv

10、Result.setText(myStr.substring(0,myStr.length()-1); catch(Exception e) tvResult.setText();break; case R.id.btnCE:tvResult.setText(null); break; /btn09case R.id.btn0:if(isClickEqu)tvResult.setText(null); isClickEqu=false;String myString=tvResult.getText().toString(); myString+=0; tvResult.setText(myS

11、tring);break;case R.id.btn1:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString1=tvResult.getText().toString();myString1+=1;tvResult.setText(myStringl);break;case R.id.btn2:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString2=tvResult.getText().toString();mySt

12、ring2+=2;tvResult.setText(myString2);break;case R.id.btn3:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString3=tvResult.getText().toString();myString3+=3;tvResult.setText(myString3);break;case R.id.btn4:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString4=tvRe

13、sult.getText().toString();myString4+=4;tvResult.setText(myString4);break;case R.id.btn5:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString5=tvResult.getText().toString();myString5+=5;tvResult.setText(myString5);break;case R.id.btn6:if(isClickEqu) tvResult.setText(null); isClickE

14、qu=false;String myString6=tvResult.getText().toString();myString6+=6;tvResult.setText(myString6);break;case R.id.btn7:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString7=tvResult.getText().toString();myString7+=7;tvResult.setText(myString7);break;case R.id.btn8:if(isClickEqu) tv

15、Result.setText(null); isClickEqu=false;String myString8=tvResult.getText().toString();myString8+=8;tvResult.setText(myString8);Break;case R.id.btn9:if(isClickEqu) tvResult.setText(null); isClickEqu=false;String myString9=tvResult.getText().toString();myString9+=9;tvResult.setText(myString9);break;bu

16、tton+*/=case R.id.btnAdd:String myStringAdd=tvResult.getText().toString();if(myStringAdd.equals(null)return;num1=Double.valueOf(myStringAdd);a = myStringAdd.length();myStringAdd += +;tvResult.setText(myStringAdd);op=1;isClickEqu=false;break;case R.id.btnSub:String myStringSub=tvResult.getText().toSt

17、ring(); if(myStringSub.equals(null)return;num1=Double.valueOf(myStringSub);a = myStringSub.length();myStringSub +=-;tvResult.setText(myStringSub);op=2;isClickEqu=false;break;case R.id.btnMul:String myStringMul=tvResult.getText().toString();if(myStringMul.equals(null)return;num1=Double.valueOf(myStri

18、ngMul);a = myStringMul.length();myStringMul += x ;tvResult.setText(myStringMul);op=3;isClickEqu=false;break;case R.id.btnDiv:String myStringDiv=tvResult.getText().toString();if(myStringDiv.equals(null)return;num1=Double.valueOf(myStringDiv);a = myStringDiv.length();myStringDiv += +;tvResult.setText(myStringDiv);op=4;isClickEqu=false;break;case R.id.btnEqu:String myStringEqu=tvResult.getText().toString();if(myStringEqu.equals(null)return;num2=Double.valueOf(myStringEqu.substring(a+1, myStrin