如何显示我的SQLite数据并将其绑定到适配器，然后将其显示在recylcerviewer android中。
这是我下面课程的全部代码。是否有可能我不需要让SQLite数据库直接通过json响应发布我的数据？如果可能的话我应该怎么做？我只是按照一些教程
Login.java
public class LoginActivity extends Activity {
private static final String TAG = RegisterActivity.class.getSimpleName();
private Button btnLogin;
private Button btnLinkToRegister;
private EditText inputUsername;
private EditText inputPassword;
private ProgressDialog pDialog;
private SessionManager session;
private SQLiteHandler db;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
inputUsername = (EditText) findViewById(R.id.username);
inputPassword = (EditText) findViewById(R.id.password);
btnLogin = (Button) findViewById(R.id.btnLogin);
btnLinkToRegister = (Button) findViewById(R.id.btnLinkToRegisterScreen);
// Progress dialog
pDialog = new ProgressDialog(this);
pDialog.setCancelable(false);
// SQLite database handler
db = new SQLiteHandler(getApplicationContext());
// Session manager
session = new SessionManager(getApplicationContext());
// Check if user is already logged in or not
if (session.isLoggedIn()) {
// User is already logged in. Take him to main activity
Intent intent = new Intent(LoginActivity.this, MainActivity.class);
startActivity(intent);
finish();
}
// Login button Click Event
btnLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String username = inputUsername.getText().toString().trim();
String password = inputPassword.getText().toString().trim();
// Check for empty data in the form
if (!username.isEmpty() && !password.isEmpty()) {
// login user
checkLogin(username, password);
} else {
// Prompt user to enter credentials
Toast.makeText(getApplicationContext(),
"Please enter the credentials!", Toast.LENGTH_LONG)
.show();
}
}
});
// Link to Register Screen
btnLinkToRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Uri uri = Uri.parse("http://gsac.ph/iaccswebportal/register.php");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
});
}
/**
* function to verify login details in mysql db
* */
private void checkLogin(final String username, final String password) {
// Tag used to cancel the request
String tag_string_req = "req_login";
pDialog.setMessage("Logging in ...");
showDialog();
StringRequest strReq = new StringRequest(Method.POST,
AppConfig.URL_LOGIN, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "Login Response: " + response.toString());
hideDialog();
try {
JSONObject jsonObject = new JSONObject(response.toString());
Log.d(TAG, "Checking JSON Object" +jsonObject);
// Check for error node in json
if (!jsonObject.isNull("login")) {
JSONObject loginObject = (JSONObject) jsonObject.get("login");
// access individual json object thru jsonObject.get("FIELD_NAME")
Log.d("TEST", "-error attribute : " + loginObject.get("error").toString());
Log.d("TEST", "-user attribute : " + loginObject.get("user").toString());
// user successfully logged in
// Create login session
session.setLogin(true);
if (!loginObject.isNull("user")) {
// handle user login data
JSONObject userJSONObject = (JSONObject) loginObject.get("user");
Log.d("USER", "User Object : " + userJSONObject.toString());
String br_code = userJSONObject.getString("br_code");
Log.d("USER", "-br_code attribute : " + userJSONObject.get("br_code").toString());
String mem_id = userJSONObject.getString("mem_id");
Log.d("USER", "-mem_id attribute : " + userJSONObject.get("mem_id").toString());
String username = userJSONObject.getString("username");
Log.d("USER", "-username attribute : " + userJSONObject.get("username").toString());
String email = userJSONObject.getString("email");
Log.d("USER", "-email attribute : " + userJSONObject.get("email").toString());
String created_at = userJSONObject.getString("created_at");
Log.d("USER", "-created_at attribute : " + userJSONObject.get("created_at").toString());
Log.d("USER", "--------------------------------------------------------------------------------------------");
// Inserting row in users table
db.addUser(br_code, mem_id, username, email, created_at);
} else {
// a new JSON string that doesn't have user in login Object
Log.d("USER", "Unknown JSON String : " + loginObject.toString());
}
//SL Details
if (!jsonObject.isNull("accounts")) {
JSONObject accountsObject = (JSONObject) jsonObject.get("accounts");
// access individual json object thru jsonObject.get("FIELD_NAME")
Log.d("SL_SUMM", "-error attribute : " + accountsObject.get("error").toString());
JSONArray slArray = accountsObject.optJSONArray("sl_summ");
// Check if its login data i.e. user present
if (slArray != null) {
// handle account data
JSONArray array = ((JSONArray)accountsObject.getJSONArray("sl_summ"));
// access individual json array thru jsonObject.getJSONArray("FIELD_NAME")
Log.d("SL_SUMM", "-sl_summ array : " + accountsObject.getJSONArray("sl_summ").toString());
for (int index=0; index<array.length(); index++) {
JSONObject object = (JSONObject)array.get(index);
String sl_desc= object.getString("sl_desc");
Log.d("SL_SUMM", "-sl_desc attribute : " + object.get("sl_desc").toString());
String tr_date= object.getString("tr_date");
Log.d("SL_SUMM", "-tr_date attribute : " + object.get("tr_date").toString());
String actual_balance= object.getString("actual_balance");
Log.d("SL_SUMM", "-actual_balance attribute : " + object.get("actual_balance").toString());
String available_balance= object.getString("available_balance");
Log.d("SL_SUMM", "-available_balance attribute : " + object.get("available_balance").toString());
Log.d("SL_SUMM", "----------------------------------------------------------------------------------");
db.addUserSLDTL(sl_desc, tr_date, actual_balance, available_balance);
}
} else {
// a new JSON string that doesn't have sl_summ as member variable so display it and write new handler code
Log.d("SL_SUMM", "Unknown JSON String : " + jsonObject.toString());
}
}
// Launch main activity
Intent intent = new Intent(LoginActivity.this, MainActivity.class);
startActivity(intent);
finish();
} else {
// Error in login. Get the error message
String errorMsg = jsonObject.getString("error_msg");
Toast.makeText(getApplicationContext(),errorMsg, Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
Log.d("TEST", e.toString());
Toast.makeText(getApplicationContext(), "Json error: " + e.getMessage(), Toast.LENGTH_LONG).show();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Login Error: " + error.getMessage());
Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_LONG).show();
hideDialog();
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting parameters to login url
Map<String, String> params = new HashMap<String, String>();
params.put("username", username);
params.put("password", password);
return params;
}
};
// Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
}
SQLiteHanlder.java
public class SQLiteHandler extends SQLiteOpenHelper {
private static final String TAG = SQLiteHandler.class.getSimpleName();
// All Static variables
// Database Version
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "test_db";
// Table name
private static final String TABLE_MEMBERS = "members";
private static final String TABLE_MEMBERS_SLDTL = "sldtl";
// members Table Column name
private static final String BR_CODE = "br_code";
private static final String MEM_ID = "mem_id";
private static final String MEM_USERNAME = "username";
private static final String MEM_EMAIL = "email";
private static final String MEM_CREATED_AT = "created_at";
// sldtl Table Column name
private static final String SL_DESC = "sl_desc";
private static final String TR_DATE = "trans_date";
private static final String ACTUAL_BALANCE = "actual_balance";
private static final String AVAILABLE_BALANCE = "available_balance";
// Table Create Statements
// Members table create statement
private static final String CREATE_MEMBERS_TABLE = "CREATE TABLE " + TABLE_MEMBERS + "("
+ BR_CODE + " INTEGER,"
+ MEM_ID + " INTEGER PRIMARY KEY,"
+ MEM_USERNAME + " TEXT,"
+ MEM_EMAIL + " TEXT UNIQUE,"
+ MEM_CREATED_AT + " TEXT" + ")";
// SLDTL table create statement
private static final String CREATE_SLDTL_TABLE = "CREATE TABLE " + TABLE_MEMBERS_SLDTL + "("
+ SL_DESC + " TEXT,"
+ TR_DATE + " DATETIME,"
+ ACTUAL_BALANCE + " REAL,"
+ AVAILABLE_BALANCE + " REAL" + ")";
public SQLiteHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
// Creating required tables
db.execSQL(CREATE_MEMBERS_TABLE);
db.execSQL(CREATE_SLDTL_TABLE);
Log.d(TAG, "Table members and sldtl was successfully created");
}
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// on upgrade drop existing tables
db.execSQL("DROP TABLE IF EXISTS " + TABLE_MEMBERS);
db.execSQL("DROP TABLE IF EXISTS " + TABLE_MEMBERS_SLDTL);
Log.d(TAG, "Drop table members and sldtl if exists");
// Creating new tables
onCreate(db);
}
/**
* Storing user details in database
* */
public void addUser(String br_code, String mem_id, String username, String email, String created_at) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(BR_CODE, br_code); // branch code
values.put(MEM_ID, mem_id); // mem id
values.put(MEM_USERNAME, username); // username
values.put(MEM_EMAIL, email); // Email
values.put(MEM_CREATED_AT, created_at); // Created At
// Inserting Row
long id = db.insertOrThrow(TABLE_MEMBERS, null, values);
db.close(); // Closing database connection
Log.d(TAG, "Member's info was inserted successfully: " + id);
Log.d(TAG, "BR CODE: " + br_code);
Log.d(TAG, "Member ID: " + mem_id);
Log.d(TAG, "Username: " + username);
Log.d(TAG, "Email: " + email);
Log.d(TAG, "Created at: " + created_at);
Log.d(TAG, "---------------------------------");
}
/**
* Getting user data from database
* */
public HashMap<String, String> getUserDetails() {
HashMap<String, String> user = new HashMap<String, String>();
String selectQuery = "SELECT * FROM " + TABLE_MEMBERS;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// Move to first row
cursor.moveToFirst();
if (cursor.getCount() > 0) {
user.put("br_code", cursor.getString(0));
user.put("mem_id", cursor.getString(1));
user.put("username", cursor.getString(2));
user.put("email", cursor.getString(3));
user.put("created_at", cursor.getString(4));
Log.d(TAG, "Members's data: " + user.toString());
}
else{
Log.d(TAG, "member's data is empty");
}
cursor.close();
db.close();
// return user
Log.d(TAG, "Member's info was successfully fetch: " + user.toString());
return user;
}
/**
* Storing user SL details in database
* */
public void addUserSLDTL(String sl_desc, String tr_date, String actual_balance, String available_balance){
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(SL_DESC, sl_desc); // sl desc
values.put(TR_DATE, tr_date); // trans date
values.put(ACTUAL_BALANCE, actual_balance); // actual balance
values.put(AVAILABLE_BALANCE, available_balance); // availabe balance
// Inserting Row
long id = db.insertOrThrow(TABLE_MEMBERS_SLDTL, null, values);
db.close(); // Closing database connection
Log.d(TAG, "Members's SL Details was successfully: " + id);
Log.d(TAG, "SL Desc: " + sl_desc);
Log.d(TAG, "Transaction Date: " + tr_date);
Log.d(TAG, "Actual Balance: " + actual_balance);
Log.d(TAG, "Available Balance: " + available_balance);
}
/**
* Getting user SL details data from database
* */
public HashMap<String, String> getUserSLDTL() {
HashMap<String, String> sl_summ = new HashMap<String, String>();
String selectQuery = "SELECT * FROM " + TABLE_MEMBERS_SLDTL;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// Move to first row
cursor.moveToFirst();
if (cursor.getCount() > 0) {
sl_summ.put("sl_desc", cursor.getString(0));
sl_summ.put("tr_date", cursor.getString(1));
sl_summ.put("actual_balance", cursor.getString(2));
sl_summ.put("available_balance", cursor.getString(3));
Log.d(TAG, "Member's SL Details: " + sl_summ.toString());
}
else{
Log.d(TAG, "member's SLDTL data is empty");
}
cursor.close();
db.close();
// return user
Log.d(TAG, "Member's SL Details was successfully fetch: " + sl_summ.toString());
return sl_summ;
}
/**
* Getting user data from database
* */
public List<Datas> getUserSLDetails() {
String selectQuery = "SELECT * FROM " + TABLE_MEMBERS;
List<Datas> mMemberDetails = new ArrayList<>();
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// Move to first row
cursor.moveToFirst();
if (cursor.getCount() > 0) {
Datas pMemebr = new Datas();
pMemebr.setSL_DESC(cursor.getString(0));
pMemebr.setTR_DATE(cursor.getString(1));
pMemebr.setACTUAL_BALANCE(cursor.getString(2));
pMemebr.setAVAILABLE_BALANCE(cursor.getString(3));
mMemberDetails.add(pMemebr);
Log.d(TAG, "Members's data: " + pMemebr.toString());
}
else{
Log.d(TAG, "member's data is empty");
}
cursor.close();
db.close();
return mMemberDetails;
}
/**
* Re create database Delete all tables and create them again
* */
public void deleteUsers() {
SQLiteDatabase db = this.getWritableDatabase();
// Delete All Rows
db.delete(TABLE_MEMBERS, null, null);
db.close();
Log.d(TAG, "All member's info are now deleted in sqlite");
}
/**
* Re create database Delete all tables and create them again
* */
public void deleteUserSLDTL() {
SQLiteDatabase db = this.getWritableDatabase();
// Delete All Rows
db.delete(TABLE_MEMBERS_SLDTL, null, null);
db.close();
Log.d(TAG, "All member's SLDTL info are now deleted in sqlite");
}
}
AccountsFragment.java
public class AccountsFragment extends Fragment {
public AccountsFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_accounts, container, false);
RecyclerView rv = (RecyclerView) rootView.findViewById(R.id.rv_recycler_view);
rv.setHasFixedSize(true);
MyAdapter adapter = new MyAdapter(new String[]{"test one", "test two"});
rv.setAdapter(adapter);
LinearLayoutManager llm = new LinearLayoutManager(getActivity());
rv.setLayoutManager(llm);
return rootView;
}
}
MyAdapter.java
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private String[] mDataset;
// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder
public static class MyViewHolder extends RecyclerView.ViewHolder {
public CardView mCardView;
public TextView account_type;
public TextView accnt_description;
public TextView balance_label;
public TextView account_balance;
public MyViewHolder(View v) {
super(v);
mCardView = (CardView) v.findViewById(R.id.card_view);
account_type = (TextView) v.findViewById(R.id.lblShareCapital);
balance_label = (TextView) v.findViewById(R.id.lblAvailableBalance);
accnt_description = (TextView) v.findViewById(R.id.sl_desc);
account_balance = (TextView) v.findViewById(R.id.actual_balance);
}
}
// Provide a suitable constructor (depends on the kind of dataset)
public MyAdapter(String[] myDataset) {
mDataset = myDataset;
}
// Create new views (invoked by the layout manager)
@Override
public MyAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent,
int viewType) {
// create a new view
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.card_item, parent, false);
// set the view's size, margins, paddings and layout parameters
MyViewHolder vh = new MyViewHolder(v);
return vh;
}
@Override
public void onBindViewHolder(MyViewHolder holder, final int position) {
holder.account_type.setText(mDataset[position]);
holder.mCardView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String currentValue = mDataset[position];
Log.d("CardView", "CardView Clicked: " + currentValue);
}
});
}
@Override
public int getItemCount() {
return mDataset.length;
}
}
Datas.java
public class Datas {
private String SL_DESC;
private String TR_DATE;
private String ACTUAL_BALANCE;
private String AVAILABLE_BALANCE;
public String getSL_DESC() {
return SL_DESC;
}
public void setSL_DESC(String SL_DESC) {
this.SL_DESC = SL_DESC;
}
public String getTR_DATE() {
return TR_DATE;
}
public void setTR_DATE(String TR_DATE) {
this.TR_DATE = TR_DATE;
}
public String getACTUAL_BALANCE() {
return ACTUAL_BALANCE;
}
public void setACTUAL_BALANCE(String ACTUAL_BALANCE) {
this.ACTUAL_BALANCE = ACTUAL_BALANCE;
}
public String getAVAILABLE_BALANCE() {
return AVAILABLE_BALANCE;
}
public void setAVAILABLE_BALANCE(String AVAILABLE_BALANCE) {
this.AVAILABLE_BALANCE = AVAILABLE_BALANCE;
}
}
答案 0 :(得分：0)
更改 AccountFragment 以下行
MyAdapter adapter = new MyAdapter(new String[]{"test one", "test two"});
到
SQLiteHandler db = new SQLiteHandler(getActivity());
MyAdapter adapter = new MyAdapter(db.getUserSLDetails());
然后在 MyAdapter 类中将第一行中的数据集声明更改为 -
private List<Datas> mDataset;
构造函数到
public MyAdapter(List<Datas> myDataset) {
mDataset = myDataset;
}
然后在onBindViewHolder方法中
Datas datas = mDataset.get(position);
holder.account_balance.setText(datas.getACTUAL_BALANCE());
完成所有3个更改，然后编译并运行。