Question

我浏览标签后，我在列表中的列表视图内容（使用视图寻呼机的可切换的tans）似乎消失了。我有三个选项卡Polygon，Line，Point。一旦我浏览列表视图中的所有三个选项卡内容消失。我通过将数据从活动传递到每个片段来获取我的内容以填充listview。 `

 class ViewPagerAdapter extends FragmentPagerAdapter {
    int noOfTabs;

    public ViewPagerAdapter(FragmentManager fm, int noOfTabs ) {
        super(fm);
        this.noOfTabs = noOfTabs;

    }

    @Override
    public Fragment getItem(int position) {
        Bundle bundle = new Bundle();
        switch (position) {
            case 0:
                SavedPolygonFragment polyFrag = new SavedPolygonFragment();

                for (int i = 0; i<savedShapes.size(); i++) {
                    bundle.putParcelable("extras" + i, savedShapes.get(i));
                }
                polyFrag.setArguments(bundle);
                return polyFrag;

            case 1:
                SavedLineFragment lineFrag = new SavedLineFragment();
                for (int i = 0; i<savedLines.size(); i++) {
                    bundle.putParcelable("extras" + i, savedLines.get(i));
                }
                lineFrag.setArguments(bundle);
                return lineFrag;
            case 2:
                SavedPointFragment pointFrag = new SavedPointFragment();
                for (int i = 0; i<savedPois.size(); i++) {
                    bundle.putParcelable("extras" + i, savedPois.get(i));
                }
                pointFrag.setArguments(bundle);
                return pointFrag;
            default:
                return null;
        }
    }

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

}`

这是我从中获取所有三个选项卡的数据库数据的活动。

我的 SavedPolygonFragment.java 看起来像这样

package com.miraglo.drawing.fragment;


public class SavedPolygonFragment extends android.support.v4.app.Fragment {
private static String LOG_TAG = SavedPolygonFragment.class.getName();

private String message = "No message";
private ListView shapeList;
private SavedShapeAdapter savedShapeAdapter;
private long        projId;
private float       scaleFactor;
private List<Shape> savedShapes = new ArrayList<>();

public SavedPolygonFragment() {

}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View view = inflater.inflate(R.layout.fragment_one, container, false);


    for (String key : getArguments().keySet()) {
        savedShapes.add(getArguments().<Shape>getParcelable(key));
    }

    shapeList = (ListView) view.findViewById(R.id.shapeList);


    return view;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Toast.makeText(getActivity(), "Here poly create",Toast.LENGTH_SHORT).show();
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    Toast.makeText(getActivity(), "Here",Toast.LENGTH_SHORT).show();
    if (savedShapeAdapter != null) {
        savedShapeAdapter.notifyDataSetChanged();
    } else {

        savedShapeAdapter = new SavedShapeAdapter(savedShapes, getActivity());
        shapeList.setAdapter(savedShapeAdapter);

        shapeList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

                Toast.makeText(getActivity(), " " + String.valueOf(((Shape) view.getTag()).getShapeId()), Toast.LENGTH_SHORT).show();
            }
        });
    }

}

}

Answer 1

OMG终于找到了修复程序。发布答案，以便有一天有人不会偶然发现这个麻烦制造者..只需添加这个

mViewPager.setOffscreenPageLimit(2);

感谢this post。花了一段时间才找到它。

刷卡后，可切换视图内容消失

1 个答案: