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如何使用Android Studio计算Java中的总和_Java_Android_String_Sum - Fatal编程技术网

如何使用Android Studio计算Java中的总和

如何使用Android Studio计算Java中的总和,java,android,string,sum,Java,Android,String,Sum,我刚刚用Android Studio学习了Java 使用整数计算和的代码错误 我尝试将字符串解码为整数,但仍然出错 protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); edtvalue = (EditText) findViewById(R.i

我刚刚用Android Studio学习了Java

使用整数计算和的代码错误

我尝试将字符串解码为整数,但仍然出错

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        edtvalue = (EditText) findViewById(R.id.value);
        final Spinner edtjw = (Spinner) findViewById(R.id.spinner1);
        txtpa = (TextView) findViewById(R.id.pa);
        txttotal = (TextView) findViewById(R.id.total);

        btncount.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String value = edtvalue.getText().toString().trim();
                String jw = edtjw.getSelectedItem().toString().trim();

                double h = Double.parseDouble(value);
                double j = Double.parseDouble(jw);

                String numbertostring = String.format ("%.2f", (0.02*h));
                String numbertostring2 = String.format ("%.2f", (0.025*h));
                String numbertostring3 = String.format ("%.2f", (0.0275*h));
                if (j == 1){
                    txtpa.setText(numbertostring);
                } else if (j ==2){
                    txtpa.setText(numbertostring);
                } else if (j ==3){
                    txtpa.setText(numbertostring);
                } else if (j ==4){
                    txtpa.setText(numbertostring2);
                } else  if (j ==5){
                    txtpa.setText(numbertostring3);
                } else {
                    txtpa.setText(0);
                }

                int tot = (h*j)+txtpa;
                txttotal.setText("Total : "  + tot);
}}

通过查看代码段,您应该从TextView类型的txtpa获取字符串值,然后将其解析为double

double tot=h*j+double.parseDoubletxtpa.getText.toString


如Naitik Soni在上述评论中所述。

Hi,欢迎来到Stack Overflow。你说你有错误,你能告诉我们错误是什么吗?请尽可能详细地告诉我们您的问题,以便我们能够帮助您。您遇到了什么错误?添加您得到的错误/异常的内容。我想添加int h、int j和字符串txtpa的总和。你能帮我吗?试试double total=h*j+double.parseDoubletxtpa.getText.toString;tot应该是双精度的,而不是整数