点击等号，一点反应都没有，求大神帮忙看看
public class MainActivity extends Activity implements OnClickListener {
// 声明控件
Button btn_0, btn_1, btn_2, btn_3, btn_4, btn_5, btn_6, btn_7, btn_8,
btn_9, btn_add, btn_minus, btn_multiply, btn_divide, btn_del,
btn_clear, btn_point, btn_equel;
EditText et_input;
boolean clear_flag;//清空标识
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// 绑定控件
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_add = (Button) findViewById(R.id.btn_add);
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_del = (Button) findViewById(R.id.btn_del);
btn_clear = (Button) findViewById(R.id.btn_clear);
btn_point = (Button) findViewById(R.id.btn_point);
btn_equel = (Button) findViewById(R.id.btn_equel);
et_input = (EditText) findViewById(R.id.et);
// 设置按钮的点击事件
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_add.setOnClickListener(this);
btn_minus.setOnClickListener(this);
btn_multiply.setOnClickListener(this);
btn_divide.setOnClickListener(this);
btn_del.setOnClickListener(this);
btn_clear.setOnClickListener(this);
btn_point.setOnClickListener(this);
btn_equel.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// 判断点击的是那个按钮
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("");
}//清空标志位
// 将输入的字符添加到输入框中
et_input.setText(str + ((Button) v).getText());
break;
case R.id.btn_add:
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_equel :
getResult();
break;
default:
break;
}
}
//计算结果
public 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(" "));//截取字符串前面的字符
String op = exp.substring(exp.indexOf(" ")+1, exp.indexOf(" ")+2);//运算符
String s2 = exp.substring(exp.indexOf(" ")+3);//运算符后面的字符串
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 = d1/d2;
}else{
result = 0 ;
}
}
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("");
}
}
}
