java - 从 fragment 返回到上一个 Activity

Question

我有一个 FragmentActivity，当用户按下后退按钮时，它会关闭应用程序。

为了尝试解决这个问题，我尝试过:

@Override
 public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
    onBackPressed();

}

return super.onKeyDown(keyCode, event);
}
@Override
public void onBackPressed() {
   Log.d("CDA", "onBackPressed Called");
   Intent intent = new Intent(this, betaEventsActivity.class);
   startActivity(intent);
}

问题是这不能很好地工作。它只是将用户带到指定的 Activity ，不一定返回到之前的 Activity 。

我也试过:

@Override
     public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
        Intent intent = new Intent(Intent.ACTION_MAIN);
        intent.addCategory(Intent.CATEGORY_HOME);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);//***Change Here***
        startActivity(intent);
        finish();
        System.exit(0);

    }

    return super.onKeyDown(keyCode, event);
    }

但这只会关闭应用程序。

下面是我的 FragmentActivity 代码:

public class usermatch extends FragmentActivity {
    private PageAdapter mPagerAdapter;
    private FeedbackDialog feedBack;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.viewpager_layout);
        initialisePaging();
        feedBack = new FeedbackDialog(this, "id");


    }

    private void initialisePaging() {
        // TODO Auto-generated method stub
        List<Fragment> fragments = new Vector<Fragment>();
        fragments.add(Fragment.instantiate(this, Fragment1.class.getName()));
        fragments.add(Fragment.instantiate(this, Fragment2.class.getName()));
        fragments.add(Fragment.instantiate(this, Fragment3.class.getName()));
        fragments.add(Fragment.instantiate(this, Fragment4.class.getName()));
        fragments.add(Fragment.instantiate(this, Fragment5.class.getName()));



        mPagerAdapter = new PageAdapter(this.getSupportFragmentManager(), fragments);
        ViewPager pager = (ViewPager) findViewById(R.id.viewpager);
        pager.setAdapter(mPagerAdapter);

    }

    @Override
     public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
        Intent intent = new Intent(Intent.ACTION_MAIN);
        intent.addCategory(Intent.CATEGORY_HOME);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);//***Change Here***
        startActivity(intent);
        finish();
        System.exit(0);

    }

    return super.onKeyDown(keyCode, event);
    }

如有任何帮助，我们将不胜感激。

Answer 1

尝试不覆盖 onBackPressed()。