Java Android简单兴趣计算器

我是Android环境的初学者程序员。我需要你的帮助

这就是我要做的

---

我的xml：

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:paddingBottom="@dimen/activity_vertical_margin"
        android:paddingLeft="@dimen/activity_horizontal_margin"
        android:paddingRight="@dimen/activity_horizontal_margin"
        android:paddingTop="@dimen/activity_vertical_margin"
        tools:context=".SICalculatorActivity" >

        <TextView
            android:id="@+id/Years"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/IR_bar"
            android:layout_centerVertical="true"
            android:text="2 Year(s)"
            android:textSize="20sp" />

        <SeekBar
            android:id="@+id/year_bar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/Years"
            android:layout_below="@+id/Years"
            android:layout_marginTop="21dp" />

        <Button
            android:id="@+id/calculate"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/year_bar"
            android:layout_alignParentBottom="true"
            android:layout_alignRight="@+id/year_bar"
            android:text="Calculate" />

        <EditText
            android:id="@+id/IR_bar"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_above="@+id/Years"
            android:layout_marginBottom="14dp"
            android:ems="10"
            android:inputType="number" >

            <requestFocus />
        </EditText>

        <TextView
            android:id="@+id/Interest_Rate"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_above="@+id/IR_bar"
            android:layout_alignLeft="@+id/IR_bar"
            android:layout_marginBottom="15dp"
            android:text="Interest Rate"
            android:textSize="20sp" />

        <TextView
            android:id="@+id/PA"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/PA_bar"
            android:layout_alignParentTop="true"
            android:layout_marginTop="14dp"
            android:text="Principal Amount"
            android:textSize="20sp" />

        <EditText
            android:id="@+id/PA_bar"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/Interest_rate"
            android:layout_below="@+id/PA"
            android:layout_marginTop="17dp"
            android:ems="10"
            android:inputType="number" />

    </RelativeLayout>

---

---

实际上，我需要非xml部分的帮助。我需要java编码部分的帮助。即使我尝试使用onclicklistener，编译器是否总是在编码页面上显示错误？有人能帮我吗？

您的代码中有语法错误。您缺少右括号和分号

calculate.setOnClickListener(new OnClickListener() {

    public void onClick(View v){


    }
}); //<--- Change is here.

calculate.setOnClickListener（新的OnClickListener（）{
公共void onClick（视图v）{
}
}); // 试试这个：

public class MainActivity extends Activity  {
 TextView PA;
 TextView Interest_Rate;
 TextView Years;
 EditText PA_bar;
 EditText IR_bar;
 EditText  year_bar;
 Button   calculate;
 TextView t1;

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

    PA = (TextView) findViewById(R.id.PA);
    Interest_Rate = (TextView) findViewById(R.id.Interest_Rate);
    Years = (TextView) findViewById(R.id.Years);
    PA_bar = (EditText) findViewById(R.id.PA_bar);
    IR_bar = (EditText) findViewById(R.id.IR_bar);
    year_bar = (EditText) findViewById(R.id.year_bar);
    calculate = (Button) findViewById(R.id.calculate);
    t1 = (TextView) findViewById(R.id.t1);

    calculate.setOnClickListener(new View.OnClickListener()
    {
        public void onClick(View v) {
            int num1 = Integer.parseInt(PA_bar.getText().toString());
            int num2 = Integer.parseInt(IR_bar.getText().toString());
            int num = Integer.parseInt(year_bar.getText().toString());

            int si = (num1 * num2 * num) / 100;
            t1.setText(Integer.toString(si));
        }
    });
}};

在问题中加上你得到的错误。还有一个更好的主意是，用户移动搜索栏后，兴趣就会被计算出来。使视图变量
final
在
OnClickListener
中可见，然后进行计算。
public class MainActivity extends Activity  {
 TextView PA;
 TextView Interest_Rate;
 TextView Years;
 EditText PA_bar;
 EditText IR_bar;
 EditText  year_bar;
 Button   calculate;
 TextView t1;

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

    PA = (TextView) findViewById(R.id.PA);
    Interest_Rate = (TextView) findViewById(R.id.Interest_Rate);
    Years = (TextView) findViewById(R.id.Years);
    PA_bar = (EditText) findViewById(R.id.PA_bar);
    IR_bar = (EditText) findViewById(R.id.IR_bar);
    year_bar = (EditText) findViewById(R.id.year_bar);
    calculate = (Button) findViewById(R.id.calculate);
    t1 = (TextView) findViewById(R.id.t1);

    calculate.setOnClickListener(new View.OnClickListener()
    {
        public void onClick(View v) {
            int num1 = Integer.parseInt(PA_bar.getText().toString());
            int num2 = Integer.parseInt(IR_bar.getText().toString());
            int num = Integer.parseInt(year_bar.getText().toString());

            int si = (num1 * num2 * num) / 100;
            t1.setText(Integer.toString(si));
        }
    });
}};