最終局部變量無法分配，因為它是用封閉類型定義的？

Question

希望能夠在最后創建一個變量，該變量具有時間和成本的值，最終將在TextView中顯示該值。 雖然遇到了我的問題。

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    final int intTime = 30;
    final int intCost = 10;

    CheckBox CP = (CheckBox)findViewById(R.id.checkPepperoni);
    CheckBox CS = (CheckBox)findViewById(R.id.checkSausage);
    CheckBox CB = (CheckBox)findViewById(R.id.checkBacon);
    CheckBox CM = (CheckBox)findViewById(R.id.checkMushroom);

    final ImageView cheese =(ImageView)findViewById(R.id.imgCheese);
    final ImageView pepperoni =(ImageView)findViewById(R.id.imgPepperoni);
    final ImageView sausage =(ImageView)findViewById(R.id.imgSausage);
    final ImageView bacon =(ImageView)findViewById(R.id.imgBacon);
    final ImageView mushroom =(ImageView)findViewById(R.id.imgMushroom);

    final SharedPreferences sharedPref =PreferenceManager.getDefaultSharedPreferences(this);



    CP.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
                        //Pepperoni Listener
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked1) {
            // TODO Auto-generated method stub

                  if(isChecked1){                       

                      pepperoni.setImageResource(R.drawable.pepperoni);
                      intTime = intTime + 6;
                      intCost = intCost + 5;
                    }
                   else{

                        pepperoni.setImageResource(0);
                        intTime = intTime - 6;
                        intCost = intCost - 5;
                   }

    }});

    CS.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
                    //Sausage Listener
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked2) {
            // TODO Auto-generated method stub

                  if(isChecked2){                       

                      sausage.setImageResource(R.drawable.sausage);
                      intTime = intTime + 6;
                      intCost = intCost + 5;

                    }
                   else{

                       sausage.setImageResource(0);
                       intTime = intTime - 6;
                        intCost = intCost - 5;

                   }

    }});

    CB.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked3) {
            // TODO Auto-generated method stub

                  if(isChecked3){                       

                      bacon.setImageResource(R.drawable.bacon);
                      intTime = intTime + 6;
                      intCost = intCost + 5;

                    }
                   else{

                       bacon.setImageResource(0);
                       intTime = intTime - 6;
                        intCost = intCost - 5;

                   }

    }});

    CM.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked4) {
            // TODO Auto-generated method stub

                  if(isChecked4){                       

                      mushroom.setImageResource(R.drawable.mushroom);
                      intTime = intTime + 6;
                      intCost = intCost + 5;

                    }
                   else{

                       mushroom.setImageResource(0);
                       intTime = intTime - 6;
                        intCost = intCost - 5;

                   }

    }});


    ImageButton IB = (ImageButton)findViewById(R.id.imgBtnGo);
    IB.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            String time = Integer.toString(intTime);
            String cost = Integer.toString(intCost);

            SharedPreferences.Editor editor = sharedPref.edit();
            editor.putString("keyTime", time);
            editor.putString("keyCost", cost);

            startActivity(new Intent(MainActivity.this, ResultActivity.class));

        }

    });
}

}

我遇到的錯誤是“無法分配最終的局部變量intCost，因為它是用封閉類型定義的。”

這是什么意思，有什么辦法可以使用所有復選框更改此變量？

Answer 1

問題的原因是final變量在聲明時應初始化，並且不能重新分配 。 在這種情況下，最好的選擇是在匿名類中創建以最終變量值開頭的內部字段，並且該內部字段會定期更新。

例：

CP.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
    //Pepperoni Listener
    int innerTime = intTime;
    int innerCost = intCost;

    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked1) {
        if(isChecked1) {
            pepperoni.setImageResource(R.drawable.pepperoni);
            innerTime += 6;
            innerCost += 5;
        } else {
            pepperoni.setImageResource(0);
            innerTime -= 6;
            innerCost -= 5;
        }
    }
});

更多信息：

• Java教程。 匿名班

Answer 2

我不知道為什么要首先使用midficator final ，如果您只是刪除它，您的代碼將運行良好，我不確定，但是我已經檢查過onClick並且可以正常工作。 只需將它們設置為字段，就可以了