package com.example.calculatordemo;

import android.R.string;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends Activity implements OnClickListener{
?Button btn_0;//0數(shù)字按鈕
?Button btn_1;//1數(shù)字按鈕
?Button btn_2;//2數(shù)字按鈕
?Button btn_3;//3數(shù)字按鈕
?Button btn_4;//4數(shù)字按鈕
?Button btn_5;//5數(shù)字按鈕
?Button btn_6;//6數(shù)字按鈕
?Button btn_7;//7數(shù)字按鈕
?Button btn_8;//8數(shù)字按鈕
?Button btn_9;//9數(shù)字按鈕
?Button btn_point;//小數(shù)點(diǎn)按鈕
?Button btn_clear;//清除按鈕
?Button btn_del;//刪除按鈕
?Button btn_plus;//加號(hào)按鈕
?Button btn_minus;//減號(hào)按鈕
?Button btn_multiply;//乘號(hào)按鈕
?Button btn_divide;//除號(hào)按鈕
?Button btn_equal;//等于按鈕
?EditText et_input;//顯示輸入內(nèi)容的顯示屏
?boolean clear_flag;

?@Override
?protected void onCreate(Bundle savedInstanceState) {
??super.onCreate(savedInstanceState);
??setContentView(R.layout.activity_main);
??btn_0=(Button) findViewById(R.id.btn_0);
??btn_1=(Button) findViewById(R.id.btn_1);
??btn_2=(Button) findViewById(R.id.btn_2);
??btn_3=(Button) findViewById(R.id.btn_3);
??btn_4=(Button) findViewById(R.id.btn_4);
??btn_5=(Button) findViewById(R.id.btn_5);
??btn_6=(Button) findViewById(R.id.btn_6);
??btn_7=(Button) findViewById(R.id.btn_7);
??btn_8=(Button) findViewById(R.id.btn_8);
??btn_9=(Button) findViewById(R.id.btn_9);
??btn_point=(Button) findViewById(R.id.btn_point);
??btn_clear=(Button) findViewById(R.id.btn_clear);
??btn_del=(Button) findViewById(R.id.btn_del);
??btn_plus=(Button) findViewById(R.id.btn_plus);
??btn_minus=(Button) findViewById(R.id.btn_minus);
??btn_multiply=(Button) findViewById(R.id.btn_multiply);
??btn_divide=(Button) findViewById(R.id.btn_divide);
??btn_equal=(Button) findViewById(R.id.btn_equal);
??et_input=(EditText) findViewById(R.id.et_input);
??btn_0.setOnClickListener(this);
??btn_1.setOnClickListener(this);
??btn_2.setOnClickListener(this);
??btn_3.setOnClickListener(this);
??btn_4.setOnClickListener(this);
??btn_5.setOnClickListener(this);
??btn_6.setOnClickListener(this);
??btn_7.setOnClickListener(this);
??btn_8.setOnClickListener(this);
??btn_9.setOnClickListener(this);
??btn_point.setOnClickListener(this);
??btn_clear.setOnClickListener(this);
??btn_del.setOnClickListener(this);
??btn_plus.setOnClickListener(this);
??btn_minus.setOnClickListener(this);
??btn_multiply.setOnClickListener(this);
??btn_divide.setOnClickListener(this);
??btn_equal.setOnClickListener(this);
?}

?@Override
?public boolean onCreateOptionsMenu(Menu menu) {
??// Inflate the menu; this adds items to the action bar if it is present.
??getMenuInflater().inflate(R.menu.main, menu);
??return true;
?}

?@Override
?public boolean onOptionsItemSelected(MenuItem item) {
??// Handle action bar item clicks here. The action bar will
??// automatically handle clicks on the Home/Up button, so long
??// as you specify a parent activity in AndroidManifest.xml.
??int id = item.getItemId();
??if (id == R.id.action_settings) {
???return true;
??}
??return super.onOptionsItemSelected(item);
?}

?@Override
?public void onClick(View v) {
??String str=et_input.getText().toString();
?? switch (v.getId()){?
???????? case R.id.btn_0:
???????? case R.id.btn_1:
???????? case R.id.btn_2:
???????? case R.id.btn_3:
???????? case R.id.btn_4:
???????? case R.id.btn_5:
???????? case R.id.btn_6:
???????? case R.id.btn_7:
???????? case R.id.btn_8:
???????? case R.id.btn_9:
???????? case R.id.btn_point:
??????? ? if (clear_flag) {
??????? ?? clear_flag=false;
??????? ?? str="";
??????? ?? et_input.setText("");
???}
???????? et_input.setText(str+((Button)v).getText());
???????????? break;
???????? case R.id.btn_plus:
???????? case R.id.btn_minus:
???????? case R.id.btn_multiply:
???????? case R.id.btn_divide:
??????? ? if (clear_flag) {
??????? ?? clear_flag=false;
??????? ?? str="";
??????? ?? et_input.setText("");
???}
???????? et_input.setText(str+""+((Button)v).getText()+"");
???????????? break;
???????? case R.id.btn_del:
??????? ? if (clear_flag) {
??????? ?? clear_flag=false;
??????? ?? str="";
??????? ?? et_input.setText("");
???}else if (str!=null&&!str.equals("")){
???????? et_input.setText(str.substring(0,str.length()-1));
???
??}
??????? ? break;
???????? case R.id.btn_clear:
??????? ? clear_flag=false;
??????? ? str="";
???????? et_input.setText("");
??????? ? break;
???????? case R.id.btn_equal:
???????????? break;
?}
}
?private void getResult() {
??String exp=et_input.getText().toString();
??if (exp==null||exp.equals("")) {
???return;
???
??}
??if (!exp.contains("")) {
???return;
??}
??if (clear_flag) {
???clear_flag=false;
???return;
???
??}
??clear_flag=true;
??double result=0;
??String s1=exp.substring(0,exp.indexOf(""));
??String op=exp.substring(exp.indexOf("")+1,exp.indexOf("")+2);
??String s2=exp.substring(exp.indexOf("")+3);
??if (!s1.equals("")&&!s2.equals("")) {
???double d1=Double.parseDouble(s1);
???double d2=Double.parseDouble(s2);
???if (op.equals("+")) {
????result=d1+d2;
???}else if (op.equals("-")) {
????result=d1-d2;}
???else if (op.equals("×")) {
????result=d1*d2;
???}
???else if (op.equals("÷")) {
????if (d2==0) {
?????result=0;
????}else {result=d1/d2;
?????
????}
???}
???if (!s1.contains(".")&&!s2.contains(".")&&!op.equals("÷")) {
????int r=(int)result;
????et_input.setText(r+"");
???}else {
????et_input.setText(result+"");
???}
??}else if (!s1.equals("")&&s2.equals("")) {
???et_input.setText(exp);
??}else if (s1.equals("")&&!s2.equals("")) {
???double d2=Double.parseDouble(s2);
???if (op.equals("+")) {
????result=0+d2;
???}else if (op.equals("-")) {
????result=0-d2;}
???else if (op.equals("×")) {
????result=0;
???}
???else if (op.equals("÷")) {
?????result=0;
???}
???if (!s2.contains(".")) {
????int r=(int)result;
????et_input.setText(r+"");
???}else {
????et_input.setText(result+"");
???}
??}else {et_input.setText("");
???
??}
?}
}