我正在使用Recyclerview，这里是Json文件，用Json数组编写的插入查询，虽然json数据没有存储在SQLite中。当我们销毁应用程序并再次重启时它只会显示 空白行再次按一个按钮，它将显示json数据aftr emptyrow即：在销毁数据丢失后。帮我谢谢
public class Recyclerview extends AppCompatActivity {
private RecyclerView mRecyclerView;
CustomAdapter cu;
ArrayList<Employee> arr, arr1;
Toolbar toolbar;
TextView t1, t2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.recyclerview);
toolbar = (Toolbar) findViewById(R.id.toolbar1);
setSupportActionBar(toolbar);
final RecyclerView rv = (RecyclerView) findViewById(R.id.rv);
rv.setHasFixedSize(true);
arr = new ArrayList<Employee>();
arr = InitializeData();
final LinearLayoutManager llm = new LinearLayoutManager(Recyclerview.this);
rv.setLayoutManager(llm);
rv.setHasFixedSize(true);
cu = new CustomAdapter(Recyclerview.this, arr);
rv.setAdapter(cu);
registerForContextMenu(rv);
final bank ban = new bank(Recyclerview.this);
ImageButton refresh = (ImageButton) findViewById(R.id.refresh);
refresh.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Toast.makeText(Recyclerview.this, "ok", Toast.LENGTH_LONG).show();
if (isNetworkAvailable()) {
String url = ConstantValues.BASE_URL;
RequestBody formBody = new FormBody.Builder()
.add("key1", "value1")
.add("key2", "value2")
.add("key3", "value3")
.build();
try {
post(url, formBody, new Callback() {
@Override
public void onFailure(Call call, IOException e) {
Log.e("JSONDemo", "IOException", e);
}
@Override
public void onResponse(final Call call, final Response response) throws IOException {
String JSON = response.body().string();
Log.e("res", " " + JSON);
try {
JSONObject jsonObj = new JSONObject(JSON);
JSONArray resultarr = jsonObj.getJSONArray("result");
final JSONArray resultarr1 = jsonObj.getJSONArray("result1");
ban.OpenDB();
ban.OpenDB();
for (int i = 0; i < resultarr1.length(); i++) {
Employee emp = new Employee();
JSONObject result1obj = resultarr1.getJSONObject(i);
String result1Id = result1obj.getString(ConstantValues.Bank_ID);
String result1NAME = result1obj.getString(ConstantValues.Bank_NAME);
Log.e("result", " " + result1Id);
Log.e("result", " " + result1NAME);
emp.setId(result1obj.getString(ConstantValues.Bank_ID));
emp.setName(result1obj.getString(ConstantValues.Bank_NAME));
arr.add(emp);
long l = 0;
l=ban.InsertQryForTabEmpData(ConstantValues.Bank_ID,ConstantValues.Bank_NAME);
}
ban.CloseDB();
runOnUiThread(new Runnable() {
@Override
public void run() {
cu.notifyDataSetChanged();
}
});
} catch (Exception e) {
Log.e("JSONDemo", "onResponse", e);
}
}
});
} catch (Exception e) {
Log.e("JSONDemo", "Post Exception", e);
}
} else {
Toast.makeText(Recyclerview.this, "Internet not available", Toast.LENGTH_LONG).show();
}
}
});
}
private ArrayList<Employee> InitializeData() {
ArrayList<Employee> arr_emp = new ArrayList<Employee>();
bank ban = new bank(Recyclerview.this);
long l = 0;
ban.OpenDB();
arr_emp = ban.AllSelectQryForTabEmpData1();
ban.CloseDB();
return arr_emp;
}
private boolean isNetworkAvailable() {
ConnectivityManager connectivityManager
= (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
return activeNetworkInfo != null && activeNetworkInfo.isConnected();
}
private final OkHttpClient client = new OkHttpClient();
Call post(String url, RequestBody formBody, Callback callback) throws IOException {
Request request = new Request.Builder()
.url(url)
.post(formBody)
.build();
Call call = client.newCall(request);
call.enqueue(callback);
return call;
}
}
这是所有SQLite的查询：
public class bank {
private Context context;
private SQLiteDatabase SQLiteDb;
public bank(Context context){
this.context=context;
}
public static class DBHelper extends SQLiteOpenHelper{
public DBHelper(Context context) {
super(context, ConstantValues.DBName, null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(" create table if not exists " + ConstantValues.TabEmpData+"("
+ ConstantValues.Bank_ID + " text, "
+ ConstantValues.Bank_NAME + " text )");
}
@Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {
db.execSQL(" create table if not exists " + ConstantValues.TabEmpData+"("
+ ConstantValues.Bank_ID + " text, "
+ ConstantValues.Bank_NAME + " text )");
}
}
public void OpenDB() {
SQLiteDb = new DBHelper(context).getWritableDatabase();
}
public void CloseDB() {
if (SQLiteDb.isOpen()) {
SQLiteDb.close();
}
}
public long InsertQryForTabEmpData(String ID, String NAME) {
ContentValues cv = new ContentValues();
cv.put(ConstantValues.Bank_ID, ID);
cv.put(ConstantValues.Bank_NAME, NAME);
long l = SQLiteDb.insert(ConstantValues.TabEmpData, null, cv);
return l;
}
public long UpdateQryForTabEmpData(String ID
, String NAME
) {
ContentValues cv = new ContentValues();
cv.put(ConstantValues.Bank_ID, ID);
cv.put(ConstantValues.Bank_NAME, NAME);
long l = SQLiteDb.update(ConstantValues.TabEmpData, cv, ConstantValues.Bank_ID+ "=" + ID, null);
return l;
}
public long DeleteQryForTabEmpData(String ID) {
long l = SQLiteDb.delete(ConstantValues.TabEmpData, ConstantValues.Bank_ID+ "=" + ID, null);
return l;
}
public ArrayList SelectQryForTabEmpData(String ID) {
ArrayList<String> data = new ArrayList();
String[] arg = {
"ID"
, "NAME"
};
String selection = " ID= " + ID;
String QRY = " SELECT ID,NAME FROM TabEmpData WHERE ID = " + ID;// +" AND EmpFName = 'test' grup by empid,fname,lastname having Empsalary > = 2000 order by fname asc,salry desc limit 100";
Cursor cursor = SQLiteDb.rawQuery(QRY, null);//
SQLiteDb.query(ConstantValues.TabEmpData, arg, selection, null, null, null, null, null);
while (cursor.moveToNext()) {
data.add(0, cursor.getString(cursor.getColumnIndex(ConstantValues.Bank_ID)));
data.add(1, cursor.getString(cursor.getColumnIndex(ConstantValues.Bank_NAME)));
}
cursor.close();
return data;
}
public ArrayList AllSelectQryForTabEmpData1() {
ArrayList<Employee> data = new ArrayList();
Cursor cursor = SQLiteDb.query(ConstantValues.TabEmpData, null, null, null, null, null, null, null);
while (cursor.moveToNext()) {
String id = cursor.getString(cursor.getColumnIndex(ConstantValues.Bank_ID));
String name = cursor.getString(cursor.getColumnIndex(ConstantValues.Bank_NAME));
data.add(new Employee(id, name));
}
cursor.close();
return data;
}
}
我的自定义适配器：
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.EmpDataViewHolder> {
final bank ban = new bank(CustomAdapter.this.context);
private ArrayList<Employee> arr,filterlist;
private Context context;
public CustomAdapter(Context context, ArrayList<Employee> arr) {
this.arr=arr;
this.context=context;
Toast.makeText(context,""+arr.size(),Toast.LENGTH_LONG).show();
}
@Override
public EmpDataViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(context).inflate(R.layout.cardview, parent, false);
EmpDataViewHolder edvh = new EmpDataViewHolder(v);
return edvh;
}
@Override
public void onBindViewHolder(EmpDataViewHolder holder, int position) {
Employee emp=arr.get(position) ;
holder.id.setText(emp.getId());
holder.name.setText(emp.getName());
holder.cv.setTag(R.string.KeyForCV,position);
}
@Override
public int getItemCount() {
return arr.size();
}
public class EmpDataViewHolder extends RecyclerView.ViewHolder {
CardView cv;
TextView id;
TextView name;
public EmpDataViewHolder(View itemView) {
super(itemView);
cv= (CardView) itemView.findViewById(R.id.cv);
id= (TextView) itemView.findViewById(R.id.id);
name= (TextView) itemView.findViewById(R.id.name);
}
}
}
请帮助我，我想摆脱这个问题，提前谢谢