我在sqlite android中存储标题，缩略图，id，并在recyclerview中显示。我创建了所有方法，即在我的sqlite助手类中获取数据，添加，删除和更新，并在我的片段Android中调用这些方法。
，但是问题是当我删除或添加项目中的sqlite时，它没有令人耳目一新。是的，我在片段类中定义了adapter.notifydatasetChanged()。
示例：
这是我的sqlite openhelper类：
-
public List<dataModel> getDatabase(); -
public void addData(dataModel data); -
public void deleteData(dataModel data);
我在片段中调用这些方法，我正在分配 getDatabase()列在片段中。
预先感谢。编辑1：
public class LightFragment extends Fragment {
RecyclerView mRecyclerView;
FloatingActionButton addLightTitle,allLightsOff;
ArrayList<LightTitle> lightTitle;
RecyclerView.LayoutManager mLayoutManager;
EditText edxLightName;
Button btnLightName;
SQLiteDatabase db;
LDbHelper lHelper;
ArrayList<LightPojo> mLightPojos = new ArrayList<>();
LightRecyclerView li;
@SuppressLint("ValidFragment")
public LightFragment(Context mContext) {
lHelper = new LDbHelper(mContext);
}
public LightFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_light, container, false);
}
@Override
public void onPause() {
super.onPause();
mLightPojos = lHelper.getLightData();
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mRecyclerView = view.findViewById(R.id.light_frag);
addLightTitle = view.findViewById(R.id.fab_add_light_title);
allLightsOff = view.findViewById(R.id.fab_off_all_lights);
mLayoutManager = new LinearLayoutManager(getContext(),LinearLayoutManager.HORIZONTAL,false);
mLightPojos = lHelper.getLightData();
li = new LightRecyclerView(getContext(),mLightPojos);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(li);
li.notifyDataSetChanged();
mRecyclerView.addOnItemTouchListener(new RecyclerTouchListener(getActivity(),mRecyclerView,new ClickListener(){
@Override
public void onClick(View view, int position) {
Log.d("BT","clicked" + mLightPojos.get(position).getName());
//toast("clicked" + position );
if (!mLightPojos.get(position).isClicked()){
ImageView lightPopUp = view.findViewById(R.id.row_light_thumbnail);
lightPopUp.setImageResource(R.drawable.light_on);
//DrawableCompat.setTint(lightPopUp.getDrawable().mutate(), ContextCompat.getColor(getContext(), R.color.white));
toast(mLightPojos.get(position).getName() + "light on");
Log.d("BT","clicked" + mLightPojos.get(position).isClicked());
//mLightPojos.get(position).setClicked(true);
LightPojo pojo = new LightPojo(mLightPojos.get(position).getId(),R.drawable.light_on,true);
lHelper.upDateState(pojo);
}else {
ImageView lightPopUp = view.findViewById(R.id.row_light_thumbnail);
toast(mLightPojos.get(position).getName() + "light off");
lightPopUp.setImageResource(R.drawable.light_off);
//DrawableCompat.setTint(lightPopUp.getDrawable().mutate(), ContextCompat.getColor(getContext(), R.color.colorAccent));
Log.d("BT","clicked" + mLightPojos.get(position).isClicked());
//mLightPojos.get(position).setClicked(false);
//lHelper.upDateState(position,R.drawable.light_off,false);
LightPojo pojo = new LightPojo(mLightPojos.get(position).getId(),R.drawable.light_off,false);
lHelper.upDateState(pojo);
}
}
@Override
public void onLongClick(View view, final int position) {
toast("long pressed at " + position);
final Dialog eDialog = new Dialog(getActivity());
eDialog.setContentView(R.layout.edit_light_name);
//EditText editLightName = eDialog.findViewById(R.id.edit_light_name_edx);
//final String editedLightName = editLightName.getText().toString();
Button deleteLightName = eDialog.findViewById(R.id.btn_delete_light_name);
Button updateLightName = eDialog.findViewById(R.id.btn_update_light_name);
eDialog.show();
// eDialog.setTitle("Edit light name");
updateLightName.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//lightTitle.set(position,editLightName.getText().toString());
//Log.d("BT",editedLightName);
EditText editLightName = eDialog.findViewById(R.id.edit_light_name_edx);
//lightTitle.set(position,new LightTitle(editLightName.getText().toString(),false));
LightPojo pojo = new LightPojo(mLightPojos.get(position).getId(),editLightName.getText().toString());
lHelper.editName(pojo);
lHelper.getLightData();
li.notifyDataSetChanged();
eDialog.dismiss();
}
});
deleteLightName.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//lightTitle.remove(position);
LightPojo pojo = new LightPojo(mLightPojos.get(position).getId());
lHelper.delete(pojo);
li.notifyItemChanged(position);
//li.notifyDataSetChanged();
eDialog.dismiss();
}
});
}
}));
addLightTitle.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//toast("clicked fab button");
//LightTitleDialog titleDialog = new LightTitleDialog();
//titleDialog.show(getActivity().getFragmentManager(),"title");
final Dialog mDialog = new Dialog(getActivity());
mDialog.setTitle("Add light name");
mDialog.setContentView(R.layout.add_light_title);
edxLightName = mDialog.findViewById(R.id.edt_light_title);
btnLightName = mDialog.findViewById(R.id.btn_add_title);
mDialog.show();
btnLightName.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//toast("Add light");
if (edxLightName.getText().length() != 0){
String newLightName = edxLightName.getText().toString();
//lightTitle.add(new LightTitle(newLightName,false));
//add(newLightName,R.id.utilities_thumbnail,false);
lHelper.insertData(newLightName,R.drawable.light_off,false);
li.notifyDataSetChanged();
mDialog.dismiss();
}else {
toast("Please enter light name");
}
}
});
}
});
在更新数据模型后，请通过片段或活动(无论您使用什么(调用adapter.notifydatasetChanged()。然后，RecyClerview将被更新。
更新数据模型后，请致电以下方法。
adapter.notifyItemRemoved(position);
这将更新有关从列表中删除元素的适配器。
是的，我发现我必须在单击时明确更改arraylist。除了数据库更新。
将值更新为内部更新值的SQLite调用适配器方法。您无需每次更新数据时都能获取SQLite数据。