Question

我有一个这样的课程：

public class TimerActivity extends Activity
{
CountDownTimer cntTimer = null;
@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_timers);

    final ImageButton startTimerButton = (ImageButton)findViewById(R.id.timer1ImageButton);

    final EditText timerText = (EditText) findViewById(R.id.timerEditText1);

    final TextView timerTextValue = (TextView) findViewById(R.id.timerTextView);

    boolean checkstate =false;

    timerCountDown(checkstate,startTimer3Button,timerText3, timerTextValue3);
}

public void timerCountDown(boolean check,final ImageButton startTimerImageButton ,
        final EditText timerText,final TextView timerTextValue)
{
    Integer input = 0;
    if(timerText.getText().toString()!="")
        {
             input = Integer.parseInt(timerText.getText().toString())*1000 ;
        }

    CountDownTimer timer = new CountDownTimer(input, 1000)
    {
         public void onTick(long millisUntilFinished) 
         {
             timerTextValue.setText("seconds remaining: " + millisUntilFinished / 1000);
         }

         public void onFinish() 
         {
             timerTextValue.setText("done!");

         }
    };

    timerStatus(check,startTimerImageButton,timer);
}

public void timerStatus(final boolean checkstate, final ImageButton startTimer3Button ,final CountDownTimer downTimer) 
{
    startTimer3Button.setOnClickListener(new View.OnClickListener() 
    {
          public void onClick(View v) 
          {
                if(checkstate==false)
            {
                startTimer3Button.setImageResource(R.drawable.reset);
                //Error
                checkstate = true;
                downTimer.start();
            }
            else
            {
                startTimer3Button.setImageResource(R.drawable.start);
                //Error
                checkstate = false;
                downTimer.cancel();
            }
         }
        });
}

}

但是我在timerStatue方法上遇到checkstate = false和checkstate = true的错误：无法分配最终的局部变量checkstate，因为它是在封闭类型中定义的！

我搜索了谷歌和stackoverflow但没有找到我的问题的兼容答案！你能帮助我吗？提前谢谢！

Answer 1

你可以创建一个实现OnClickListener的类，甚至你当前的类都可以这样做，并以这种方式覆盖onclick()你可以访问任何变量（不仅是最终的）

示例：修改

1）让你的活动实现OnClickListener

2）覆盖活动中的onClick（）方法。

3）在班级（boolean checkstate =false;之外）

移动onCreate()

4）将startTimer3Button.setOnClickListener(...更改为startTimer3Button.setOnClickListener(TimerActivity.this);

6）将存在于timerStatus（）中的onClick（）内的代码移动到添加到活动类的onclick（）

public class TimerActivity extends Activity implements OnClickListener{


//code and methods ....

public void timerStatus(final boolean checkstate, final ImageButton startTimer3Button ,final CountDownTimer downTimer) 
{
    startTimer3Button.setOnClickListener(TimerActivity.this);
}

//code and methods ....
    @override
    public void onClick(View v){
        if(checkstate==false)
        {
            startTimer3Button.setImageResource(R.drawable.reset);
            //Error
            checkstate = true;
            downTimer.start();
        }
        else
        {
            startTimer3Button.setImageResource(R.drawable.start);
            //Error
            checkstate = false;
            downTimer.cancel();
        }
    }
}

Answer 2

我不知道您是否想要使用您的代码。这有点模糊。正如Yazan所说，最好实现OnClickListener接口以避免向其发送最终方法。那之后为什么一切都是final？您必须在类级别（类变量）中定义变量，以便轻松地从其他方法访问它们，并且onCreate()方法设置其主要值。所以，无论我修改你的代码如何，没有任何错误，但我仍然没有做它的意思：

public class TimerActivity extends Activity
{
    CountDownTimer cntTimer = null;
    ImageButton startTimerButton;
    EditText timerText;
    TextView timerTextValue;
    boolean checkstate =false;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_timers);

        startTimerButton = (ImageButton)findViewById(R.id.timer1ImageButton);

        timerText = (EditText) findViewById(R.id.timerEditText1);

        timerTextValue = (TextView) findViewById(R.id.timerTextView);

        timerCountDown();
    }

    public void timerCountDown()
    {
        Integer input = 0;
        if(timerText.getText().toString()!="")
            {
                 input = Integer.parseInt(timerText.getText().toString())*1000 ;
            }

        CountDownTimer timer = new CountDownTimer(input, 1000)
        {
             public void onTick(long millisUntilFinished) 
             {
                 timerTextValue.setText("seconds remaining: " + millisUntilFinished / 1000);
             }

             public void onFinish() 
             {
                 timerTextValue.setText("done!");

             }
        };

        timerStatus(timer);
    }

    public void timerStatus(final CountDownTimer downTimer) 
    {
        startTimerButton.setOnClickListener(new View.OnClickListener() 
        {
              public void onClick(View v) 
              {
                    if(checkstate==false)
                {
                    startTimerButton.setImageResource(android.R.drawable.ic_secure);
                    //Error
                    checkstate = true;
                    downTimer.start();
                }
                else
                {
                    startTimerButton.setImageResource(android.R.drawable.ic_delete);
                    //Error
                    checkstate = false;
                    downTimer.cancel();
                }
             }
            });
    }

}

无法分配最终的局部变量checkstate，因为它是在封闭类型中定义的

2 个答案: