Question

我得到主要活动CrimeListActivity（片段为CrimeListFragment），调用CrimePagerActivity。在清单中我写道：

   <activity android:name=".CrimePagerActivity"
        android:parentActivityName=".CrimeListActivity"
        >

在CrimePagerActivity中，我将“getParentActivityIntent”重新定义为：

   @Nullable
@Override
public Intent getParentActivityIntent() {

    boolean mSubt=getIntent().getBooleanExtra(EXTRA_CRIME_SUBTITLE,true);

    Intent intent=new Intent(this,CrimeListActivity.class);
    intent.putExtra(CrimeListFragment.SAVED_SUBTITLE_VISIBLE,mSubt);
    return intent;
}

现在我想在List活动中“捕获”这个额外的，但是我无法在OnResume和片段的OnCreate中找到这个额外的。这个问题是独一无二的因为我不是在谈论开始活动的结果，我想要的是覆盖父意图以从父发送父数据。我在哪里可以找到它？

package software.eligo.com.criminalintent;

import android.support.v4.app.Fragment;

/**
 * Created by Bermud06 on 12.07.2016.
 */
public class CrimeListActivity extends SingleFragmentActivity {
    @Override
    protected Fragment createFragment() {
        return new CrimeListFragment();
    }
}




package software.eligo.com.criminalintent;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.AppCompatActivity;

/**
 * Created by Bermud06 on 12.07.2016.
 */
public abstract class SingleFragmentActivity extends AppCompatActivity{

    protected abstract Fragment createFragment();

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

        FragmentManager fm=getSupportFragmentManager();
        Fragment fragment=fm.findFragmentById(R.id.fragmentContainer);

        if(fragment==null){
            fragment=createFragment();
            fm.beginTransaction()
                    .add(R.id.fragmentContainer,fragment)
                    .commit();
        }
    }
}


package software.eligo.com.criminalintent;

import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;

import java.util.List;
import java.util.UUID;

/**
 * Created by mragl on 31.07.2016.
 */
public class CrimePagerActivity extends AppCompatActivity {
    private ViewPager mViewPager;
    private List<Crime> mCrimes;

    private static final String EXTRA_CRIME_ID="com.bignerdranch.android.criminalintent.crime_id";
    private static final String EXTRA_CRIME_SUBTITLE="com.bignerdranch.android.criminalintent.visible_subtitle";

    public static Intent newIntent(Context packageContext, UUID crimeID,boolean subt){
        Intent intent=new Intent(packageContext,CrimePagerActivity.class);
        intent.putExtra(EXTRA_CRIME_ID,crimeID);
        intent.putExtra(EXTRA_CRIME_SUBTITLE,subt);
        return intent;
    }

    @Nullable
    @Override
    public Intent getParentActivityIntent() {

        boolean mSubt=getIntent().getBooleanExtra(EXTRA_CRIME_SUBTITLE,true);

        Intent intent=new Intent(this,CrimeListActivity.class);
        intent.putExtra(CrimeListFragment.SAVED_SUBTITLE_VISIBLE,mSubt);
        return intent;
    }

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_crime_pager);

        UUID crimeID=(UUID)getIntent().getSerializableExtra(EXTRA_CRIME_ID);

        mCrimes=CrimeLab.get(this).getCrimes();

        mViewPager=(ViewPager)findViewById(R.id.activity_crime_pager_view_pager);







        FragmentManager fragmentManager=getSupportFragmentManager();
        mViewPager.setAdapter(new FragmentStatePagerAdapter(fragmentManager) {
            @Override
            public Fragment getItem(int position) {
                Crime crime=mCrimes.get(position);
                return CrimeFragment.newInstance(crime.getId());
            }

            @Override
            public int getCount() {
                return mCrimes.size();
            }
        });

        for(int i=0;i<mCrimes.size();i++){
            if(mCrimes.get(i).getId().equals(crimeID)){
                mViewPager.setCurrentItem(i);
                break;
                }
        }

    }



}

Answer 1

在CrimeListActivity中有一个布尔mSubtitleShow，用于确定字幕的可见性。我想让父母记住它的最后一个值，并在从子PagerActivity
返回时恢复它

要在活动中保存数据，您应该覆盖onSaveInstanceState()。然后，您还原onRestoreInstanceState()中的数据。您可以在CrimeListActivity中完成所有这些操作。不应该涉及PagerActivity，因为这个布尔值不会影响第二个活动的行为。

从儿童活动中获得额外收益

1 个答案: