Question

我是android新手。我有一个滑动标签布局和一个带片段的viewpager。我已经设置了这些之间的基本链接切换标签为5（即5个标签）问题是，在每个标签中，我想使用simplecursoradapter填充列表视图，为此我需要每个片段的位置所以我可以相应地填充它。我已经在片段适配器类中获得了位置，但我无法将其传递给主要活动。另外，如何在我的片段类中访问DBadapter以从数据库中填充listview？还是有其他方法可以做到这一点？以下是我的代码。任何帮助是极大的赞赏。提前谢谢。

public class myFragment extends Fragment{
    private ListView mainList;
    public static myFragment getInstance(int position){
        myFragment MyFragment = new myFragment();
        Bundle args = new Bundle();
        args.putInt("position", position);
        MyFragment.setArguments(args);

        return MyFragment;
    }
    @Override
    public View onCreateView(LayoutInflater inflater,
            @Nullable ViewGroup container,
            @Nullable Bundle savedInstanceState) {

            View layout = inflater.inflate(R.layout.fragment_main_list,container, false);
            mainList = (ListView)layout.findViewById(R.id.mainListView);
            Bundle bundle = getArguments();

            if(bundle!=null){
                if(bundle.getInt("position")==0){
                mainList.setBackgroundColor(getResources().getColor(R.color.primary500));
            }
            else if(bundle.getInt("position")==1){
                mainList.setBackgroundColor(getResources().getColor(R.color.primary100));
            }
            else if(bundle.getInt("position")==2){
                mainList.setBackgroundColor(getResources().getColor(R.color.primary700));
            }
            else if(bundle.getInt("position")==3){
                mainList.setBackgroundColor(getResources().getColor(R.color.accent));
            }
            else if(bundle.getInt("position")==4){
                mainList.setBackgroundColor(getResources().getColor(R.color.black));
            }

            }
            return layout;
    }   

}

主要活动如下：

public class MainActivity extends ActionBarActivity {
private Toolbar toolbar;
private ViewPager mPage;
private SlidingTabLayout mTabs;
DBadapter myDb;

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

    toolbar = (Toolbar)findViewById(R.id.app_bar);
    mPage = (ViewPager)findViewById(R.id.pager);
    mTabs = (SlidingTabLayout)findViewById(R.id.tabs);
    mFab = (FloatingActionButton)findViewById(R.id.fab);

    setSupportActionBar(toolbar);
    mPage.setAdapter(new myPagerAdapter(getSupportFragmentManager()));
    mTabs.setViewPager(mPage);
}
public class myPagerAdapter extends FragmentPagerAdapter{
        String[] tabs;
        public myPagerAdapter(FragmentManager fm) {
            super(fm);
            tabs = getResources().getStringArray(R.array.tabs);
        }

        @Override
        public Fragment getItem(int position) {
            myFragment MyFragment = myFragment.getInstance(position);
            return MyFragment;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return tabs[position];
        }

        @Override
        public int getCount() {
            return 5;
        }

    }

Answer 1

使用此方法：

mPage.setOnPageChangeListener(new SimpleOnPageChangeListener() {

            @Override
            public void onPageSelected(int pos) {
              // pos is the position of fragment that app showing
        });

<强>更新
在你的视图寻呼机适配器：

public Fragment getItem(int position) {
    return new myFragment(position);
 }

在你的片段类中：

public class myFragment extends Fragment{

private int pos
public void myFragment(int position){
   this.pos = position;
}
// other code of your class

如何在Activity中获取片段的位置？

1 个答案: