我正在尝试构建一个片段,其中包含一个漂亮的 UI 的网格视图。我已经使用了一些示例代码来尝试构建它。
我真的需要跟踪并保存我的片段状态以进行方向切换(显然我需要)还是我错过了什么?从它的声音(它是 FragmentPagerAdapter 文档)看来,FragmentPagerAdapter 为我保存了所有状态......
我只想说,这是我的问题(我有 4 个片段,其中有一些文本视图):
1.当我在Fragment0上倾斜屏幕时,底层数据消失,直到我移动到Fragment2才会重新出现。
2.当我在Fragment1上倾斜屏幕时,它的底层数据和Fragment0消失了,Fragment1的数据不会重新出现,直到我转到Fragment3但当我转到Fragment2时Fragment0的数据会重新出现(就像上面的案例1一样)。
3.当我在Fragment2上倾斜屏幕时,它的底层数据和Fragment1消失,如果我转到Fragment3,Fragment1会重新出现,如果我转到Fragment0,Fragment2会重新出现。
4.当我倾斜 Fragment3 时,只有 Fragment2 消失。
我显然做错了什么,所以这是我的代码:
这是我的 onCreate(或至少其中一些):
mAdapter = new FragPagerAdapter(getSupportFragmentManager());
mPager = (ViewPager)findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
这是我的 FragmentPagerAdapter:
private class FragPagerAdapter extends FragmentPagerAdapter {
public FragPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return numFrags;
}
@Override
public Fragment getItem(int position) {
return ArrayFragment.newInstance(position, mItem2.get(position));
}
}
这是我的片段(带有我的 ArrayAdapter):
public static class ArrayFragment extends Fragment {
int mNum;
private ArrayList<Item> mItems;
private GridAdapter myGridAdapter;
private static GridView mGridView;
static ArrayFragment newInstance(int num, ArrayList<Item> items) {
ArrayFragment f = new ArrayFragment();
Bundle args = new Bundle();
args.putInt("num", num);
args.putSerializable("items", items);
f.setArguments(args);
return f;
}
@SuppressWarnings("unchecked")
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mNum = getArguments() != null ? getArguments().getInt("num") : 1;
mItems = (ArrayList<Item>) (getArguments() != null ? getArguments().getSerializable("items") : null);
myGridAdapter = new GridAdapter(getActivity().getApplicationContext(), R.layout.grid_item, mItems);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//View v = inflater.inflate(R.layout.fragment_pager_list, container, false);
View v = inflater.inflate(R.layout.grid, container, false);
View tv = v.findViewById(R.id.text);
((TextView)tv).setText("Fragment #" + mNum);
mGridView = (GridView) v.findViewById(R.id.gridview);
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
@Override
public void onStart()
{
super.onStart();
mGridView.setAdapter(myGridAdapter);
mGridView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
Toast.makeText(getActivity(), mItems.get(arg2).getSecret(), Toast.LENGTH_LONG).show();
}
});
}
public class GridAdapter extends ArrayAdapter<Item> {
private int count;
private LayoutInflater inflater;
private Context context;
private ArrayList<Item> items;
public GridAdapter(Context context, int resource,
ArrayList<Item> items_) {
super(context, resource);
count = items_.size();
items = items_;
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// TODO Auto-generated constructor stub
}
@Override
public int getCount()
{
return count;
}
@Override
public Item getItem(int position)
{
return items.get(position);
}
@Override
public long getItemId(int position)
{
return position;
}
public void setItems(ArrayList<Item> items)
{
this.items = items;
}
@Override
public View getView(int position, View convertView, ViewGroup parent)
{
View v = convertView;
try
{
v = inflater.inflate(R.layout.grid_item, null);
}
catch (NullPointerException npe)
{
npe.printStackTrace();
}
Item item = items.get(position);
try
{
TextView name = (TextView) v.findViewById(R.id.grid_att_name);
TextView value = (TextView) v.findViewById(R.id.grid_att_value);
name.setText(item.getName());
value.setText(item.getValue());
}
catch (NullPointerException npe)
{
npe.printStackTrace();
}
return v;
}
}
}