Question

我的主要课程是：

package com.myapps.myapp;

import android.os.Bundle; 
//...and all the other imports


public class MainActivity extends Activity {


    @Override
    public void onCreate(Bundle savedInstanceState) {

    //...

    }

    MoneyCalc moneyCalculator = new MoneyCalc();
    moneyCalculator.MoneyCalculate(this);

}

我的第二堂课：

package com.myapps.myapp;

public class MoneyCalc{

    public void MoneyCalculate(MainActivity activity){
        TextView textview = (TextView) activity.findViewById(R.id.MoneyResult);
        EditText edittext = (EditText) activity.findViewById(R.id.MoneyInput);
    Spinner spinner = (Spinner) activity.findViewById(R.id.MoneySpinner1);
    Spinner spinner2 = (Spinner) activity.findViewById(R.id.MoneySpinner2);
        //...
        }
}

第二类不是活动，我只保留一些方法。单击按钮时会调用MoneyCalc方法。我无法阅读MainActivity中的方法，它说：

Multiple markers at this line
    - Syntax error on token(s), misplaced construct(s)
    - Syntax error on token "this", delete this token
    - Syntax error on token "MoneyCalculate", Identifier expected after this 
     token

logcat错误：

01-24 17:13:31.071: E/AndroidRuntime(3662): FATAL EXCEPTION: main
01-24 17:13:31.071: E/AndroidRuntime(3662): java.lang.IllegalStateException: Could not find a method MoneyCalculate(View) in the activity class com.myapps.myapp.MainActivity for onClick handler on view class android.widget.Button with id 'CalculateButton'
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.view.View$1.onClick(View.java:3584)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.view.View.performClick(View.java:4202)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.view.View$PerformClick.run(View.java:17340)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.os.Handler.handleCallback(Handler.java:725)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.os.Handler.dispatchMessage(Handler.java:92)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.os.Looper.loop(Looper.java:137)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.app.ActivityThread.main(ActivityThread.java:5039)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at java.lang.reflect.Method.invokeNative(Native Method)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at java.lang.reflect.Method.invoke(Method.java:511)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at dalvik.system.NativeStart.main(Native Method)
01-24 17:13:31.071: E/AndroidRuntime(3662): Caused by: java.lang.NoSuchMethodException: MoneyCalculate [class android.view.View]
01-24 17:13:31.071: E/AndroidRuntime(3662):     at java.lang.Class.getConstructorOrMethod(Class.java:460)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at java.lang.Class.getMethod(Class.java:915)
01-24 17:13:31.071: E/AndroidRuntime(3662):     at android.view.View$1.onClick(View.java:3577)
01-24 17:13:31.071: E/AndroidRuntime(3662):     ... 11 more

Answer 1

试试这个。将您的代码放在onCreate中并检查..

@Override
public void onCreate(Bundle savedInstanceState) {

//...

  MoneyCalc moneyCalculator = new MoneyCalc();
  moneyCalculator.MoneyCalculate(this);

}

Answer 2

这应该有效：

public class MainActivity extends Activity {


    @Override
    public void onCreate(Bundle savedInstanceState) {

    }

    MoneyCalc moneyCalculator = new MoneyCalc();

    {
        moneyCalculator.MoneyCalculate(this);
    }
}

但我不确定这是你想要的，也不是一种好的编码方式。也许你应该移动moneyCalculator.MoneyCalculate（this）; to onCreate方法或已经设置了活动内容的其他地方。现在它会编译但不会工作）

无法从另一个类调用方法（android）

2 个答案: