通过包将ViewPager Activity中的值发送到Fragment

Question

我有一个ViewPager Activity,它调用代表幻灯片布局的片段.

我需要的是将值从活动传递到片段.我怎么能这样做？我尝试在onCreate()中传递一个int 2但不工作,我

活动:

@Override
protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_screen_slide);
    Intent intent = new Intent(this,ScreenSlidePageFragment.class);
    Bundle bundle = new Bundle();
    bundle.putInt("SIDE",2);
    intent.putExtras(bundle);
/**
 * Instantiate a ViewPager and a PagerAdapter
 */

    mPager = (ViewPager)findViewById(R.id.pager);
    mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
    mPager.setAdapter(mPagerAdapter);
    mPager.setOnPageChangeListener(new OnPageChangeListener() {

        @Override
        public void onPageSelected(int arg0) {
            if(itemOld > arg0){
                auxBack--;
                SIDE=1;
            }
            else if(itemOld < arg0){
                auxFront++;
                SIDE=0;
            }
        }

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onPageScrollStateChanged(int arg0) {
            // TODO Auto-generated method stub

        }
    });
}

@Override
public void onBackPressed(){
    if(mPager.getCurrentItem()==0){
        super.onBackPressed();
    }else{
        mPager.setCurrentItem(mPager.getCurrentItem()-1);
    }
} 


/**
 * A simple pager adapter that represents 5 ScreenSlidePageFragment objects, in sequence
 */

private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter{
    public ScreenSlidePagerAdapter(FragmentManager fm){
        super(fm);
    }

    @Override
    public ScreenSlidePageFragment getItem(int arg0) {
        return new ScreenSlidePageFragment();
    }

    @Override
    public int getCount() {
        //Toast.makeText(getApplicationContext(), "Num pages " + NUM_PAGES, Toast.LENGTH_LONG).show();
        return  NUM_PAGES;
    }
}

}

分段:

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle    savedInstanceState) {

    int tID = ((ScreenSlidePagerActivity)getActivity()).getIntent().getExtras().getInt("SIDE");
    Toast.makeText(getActivity(), "Side selected....." +tID,   Toast.LENGTH_LONG).show();

Answer 1

您必须通过setArguments()方法设置Bundle,而不是intent.如果您有ViewPager,则可以将参数传递给PagerAdapter,并在实例化Fragment时设置参数.

我不知道你的SIDE是如何计算的,它是什么意思,所以我展示了一般的ide.

@Override
protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_screen_slide);
    Bundle bundle = new Bundle();
    bundle.putInt("SIDE",2);
    mPager = (ViewPager)findViewById(R.id.pager);
    mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager(), bundle);
    mPager.setAdapter(mPagerAdapter);
}


private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter{

    private final Bundle fragmentBundle;

    public ScreenSlidePagerAdapter(FragmentManager fm, Bundle data){
        super(fm);
        fragmentBundle = data;
    }

    @Override
    public ScreenSlidePageFragment getItem(int arg0) {
        final ScreenSlidePageFragment f = new ScreenSlidePageFragment();
        f.setArguments(this.fragmentBundle);
        return f;
    }

    @Override
    public int getCount() {
        return  NUM_PAGES;
    }
}

分段

@Override
public void onCreate(Bundle state) {
    super.onCreate(state);
    final Bundle args = getArguments();
    final int side = args.getInt("SIDE");
}

Answer 2

这可能不是你要求的解决方案,但它是我做的,它可能会帮助某人:

在片段中创建一个公共方法:

public void doSomething(String myValue){
     // Do stuff in your fragment with myValue
}

在您的活动中,从适配器获取片段.根据添加的顺序,您知道它是哪个片段.执行您的片段方法,传入您的变量:

// Get FriendsFragment (first fragment)
MyFragment fragment = (MyFragment) mAdapter.getItem(0);
fragment.doSomething("some-value");