在Android中,如果RecyclerView未能更新数据,可能是由于以下原因:
setData()
或类似方法来更新数据集。public class MyAdapter extends RecyclerView.Adapter {
private List itemList;
// ...
public void setData(List newData) {
itemList = newData;
notifyDataSetChanged();
}
// ...
}
notifyDataSetChanged()
。public class MyViewModel extends ViewModel {
private MutableLiveData> itemListLiveData;
// ...
public LiveData> getItemListLiveData() {
if (itemListLiveData == null) {
itemListLiveData = new MutableLiveData<>();
}
return itemListLiveData;
}
public void updateItemList(List newList) {
itemListLiveData.setValue(newList);
}
}
public class MyFragment extends Fragment {
private MyAdapter adapter;
private MyViewModel viewModel;
// ...
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// ...
viewModel.getItemListLiveData().observe(getViewLifecycleOwner(), new Observer>() {
@Override
public void onChanged(List newList) {
adapter.setData(newList);
}
});
}
}
requestLayout()
方法触发重新布局。public class MyFragment extends Fragment {
private RecyclerView recyclerView;
// ...
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// ...
viewModel.getItemListLiveData().observe(getViewLifecycleOwner(), new Observer>() {
@Override
public void onChanged(List newList) {
adapter.setData(newList);
recyclerView.requestLayout(); // 触发重新布局
}
});
}
}
通过以上方法,您应该能够解决RecyclerView未更新数据的问题。