为什么一按键就闪退
package com.example.calculatordemo;
import android.R.bool;
import android.support.v7.app.ActionBarActivity;
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;
import android.widget.TextView;
public class MainActivity extends Activity implements OnClickListener {
Button btn_0;
Button btn_1;
Button btn_2;
Button btn_3;
Button btn_4;
Button btn_5;
Button btn_6;
Button btn_7;
Button btn_8;
Button btn_9;
Button btn_point;
Button btn_clear;
Button btn_del;
Button btn_plus;
Button btn_minus;
Button btn_multiply;
Button btn_divide;
Button btn_equal;
EditText et_input;
boolean clear_flag;// 清空标示
@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);
EditText 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);
}
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;
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;
et_input.setText("");
}
et_input.setText(str + " " + ((Button) v).getText() + " ");
break;
case R.id.btn_del:
if (clear_flag) {
clear_flag = false;
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;
et_input.setText("");
break;
case R.id.btn_equal:
getResult();
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(" "));// 运算符前面的内容
String op = exp.substring(exp.indexOf(" ") + 1, exp.indexOf(" ") + 2);// 运算符
String s2 = exp.substring(exp.indexOf(" ") + 3);// 运算符后面的内容
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(".")) {
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("");
}
}
}
