Android课程设计简易计算器and保存记录.docxVIP

Android课程设计简易计算器and保存记录JisuanqiMainActivity.javapackage com.example.admin.myapplication;import android.app.Activity;import android.content.Context;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.CheckBox;import android.widget.EditText;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;public class JisuanqiMainActivity extends Activity { /** * Called when the activity is first created. */ private EditText output = null; private EditText input = null; private Button btn0 = null; private Button btn1 = null; private Button btn2 = null; private Button btn3 = null; private Button btn4 = null; private Button btn5 = null; private Button btn6 = null; private Button btn7 = null; private Button btn8 = null; private Button btn9 = null; private Button btnadd = null; private Button btnsubtract = null; private Button btnmultiply = null; private Button btndivide = null; private Button btnclear = null; private Button btnresult = null; private Button btndot = null; private EditText errorzero = null; private EditText resultText = null; private Button writeButton = null; private Button readButton = null; private CheckBox appendBox = null; private EditText textView = null; private EditText displayView = null; public String FILE_NAME = fileDemo.txt; private String str = ;//保存数字 private String strold = ;//原数字 private char act = ;//记录“加减乘除等于”符号 private int count = 0;//判断要计算的次数，如果超过一个符号，先算出来一部分 private Float result = null;//计算的输出结果 private Boolean errBoolean = false;//有错误的时候为true，无错为false private Boolean flagBoolean = false;//一个标志，如果为true，可以响应运算消息，如果为false，不响应运算消息，只有前面是数字才可以响应运算消息 private Boolean flagDot = false; //小数点标志位 @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_jisuanqi_main); output = (EditText) findViewById(R.id.output); input = (Edi