Question

我正在尝试使用从前一个活动中检索的getIntent值（得分），但似乎不可能。似乎在if下的加法和减法无法检测得分。还有其他办法吗？

package com.mkyong.android;

import com.mkyong.android.R;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import android.view.View;
import android.view.View.OnClickListener;

public class App2Activity extends Activity {

    private RadioGroup radioAnswerGroup2;
    private RadioButton radioAnswerButton2;
    private Button btnSubmit2;

    Button button2;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main2);
        addListenerOnButton();


    }

    public void addListenerOnButton() {

        final Context context = this;

        radioAnswerGroup2 = (RadioGroup) findViewById(R.id.radioAnswer2);


        button2 = (Button) findViewById(R.id.button2);
        Button button2pre = (Button) findViewById(R.id.button2pre);

        Intent intent = getIntent();
        final int score = intent.getIntExtra("int", -1);
        final TextView result2 = (TextView) findViewById(R.id.txtResult2);
        result2.setText("Result counting: " + String.valueOf(score));


        button2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {


                int correctId2 = (R.id.answer2b);

                // get selected radio button from radioGroup
                int selectedId2 = radioAnswerGroup2.getCheckedRadioButtonId();

                // find the radio button by returned id
                radioAnswerButton2 = (RadioButton) findViewById(selectedId2);

                if (selectedId2==correctId2){

                     score = score + 1;
                    //show toast saying it is correct
                    //Context context = getApplicationContext();
                    //CharSequence text = ("You are correct!");
                    //int duration = Toast.LENGTH_SHORT;

                    //Toast toast = Toast.makeText(context, text, duration);
                    //toast.show();
                }
                else{

                    score = score - 1;
                    //toast incorrect
                    //Context context = getApplicationContext();
                    //CharSequence text = ("You are wrong but it's ok and the answer is Data Link");
                    //int duration = Toast.LENGTH_LONG;

                    //Toast toast = Toast.makeText(context, text, duration);
                    //toast.show();
                }   

                Intent intent2 = new Intent(App2Activity.this, App3Activity.class);
                intent2.putExtra("int", score); 
                startActivity(intent2);  

            }

        });


        button2pre.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                Intent intent = new Intent(context, AppActivity.class);
                startActivity(intent);   

            }

        });


    }

}

Answer 1

将int score移动为全局变量，以便在onClick中访问它。您还需要删除final关键字，以便在初始化后更改该值。

 public class YourActivity extends Activity{

       int score;

      public onCreate( /*...etc.*/

Answer 2

只需从以下位置删除final关键字：

final int score = intent.getIntExtra("int", -1);

因为final变量只能通过初始值设定项或赋值语句初始化一次。

了解更多here。

错误：无法分配最终的局部变量分数，因为它是在封闭类型中定义的？

2 个答案: