Question

将int变量传递给另一个类时遇到问题。我已经尝试了很多传递这个变量的方法，但没有一个有效。帮助我将变量randomNum从MainActivity传递给HistoryActivity。谢谢！

public class MainActivity extends Activity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

    ........

        int min, max;
        max = 1;
        min = 0;
        int randomNum = min + (int) (Math.random() * ((max - min) + 1));


        int backgroundImages[] = {R.drawable.background1,
                R.drawable.background2};
        final Drawable backgroundImage = getResources().getDrawable(
                backgroundImages[randomNum]);
        linearLayoutBackground.setBackgroundDrawable(backgroundImage);



        // // WHAT TO DO NOW POGA
        buttonWhatToDoNow.setOnClickListener(new View.OnClickListener() {

                .........    

            }

        });


        buttonHistory.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Intent i = new Intent(MainActivity.this, HistoryActivity.class);
                startActivity(i);
                finish();

            }
        });    
    }
}

public class HistoryActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub

            .......

        randomNum =..............;

        int backgroundImages[] = {R.drawable.background1,
                R.drawable.background2};
        final Drawable backgroundImage = getResources().getDrawable(
                backgroundImages[randomNum]);
        linearLayoutBackground.setBackgroundDrawable(backgroundImage);
    }

}

Answer 1

Intent i = new Intent(MainActivity.this, HistoryActivity.class);
i.putExtra("intVariableName", randomNum);
startActivity(i);

历史活动 in on create method例如

 Intent mIntent = getIntent();
 int intValue = mIntent.getIntExtra("intVariableName", 0);

Answer 2

假设我们有2个课程和2个活动。

如果你希望你的值在HistoryActivity中，只需在Historyactivity的类中声明值（适用于第二页），并从第一个活动到historyactivity制作一个意图....就是这样!! !!

Answer 3

在您的onclick中：

    //onclick MainActivity
    Bundle bundle = new Bundle();
    bundle.putInt("key", randomInt);
    Intent intent = new Intent(MainActivity.this, HistoryActivity.class);
    intent.putExtras(bundle);
    finish();
    startActivity(intent);

    //then in your HistoryActivity onCreate
    int randomNum = getIntent().getExtras().getInt("key");`

将变量传递给其他类

3 个答案: