使用基本适配器和列表视图显示来自 SQLite 的变量数据
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【中文标题】使用基本适配器和列表视图显示来自 SQLite 的变量数据【英文标题】：Display variable data from SQLite using base adapter and listview 【发布时间】：2015-12-01 02:53:24 【问题描述】：您好，我正在开发的应用程序包含来自解析的 json 通知，应用程序将其存储在 SQLite 中在我的代码的主要活动中显示它
public class Receiver extends ParsePushBroadcastReceiver
@Override
public void onPushReceive(Context context, Intent intent)
super.onPushReceive(context, intent);
Log.e("Push", "Clicked");
Intent i = new Intent(context, splashscreen.class);
i.putExtras(intent.getExtras());
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
Log.d("Alert: ", "Inserting from onReceive");
Bundle extras = intent.getExtras();
String jsonData = extras.getString("com.parse.Data");
JSONObject jsonObject;
try
jsonObject = new JSONObject(jsonData);
String alert = jsonObject.getString("alert");
Log.d("Insert: ",alert);
String Message = jsonObject.getString("Message");
Log.d("Title: ",Message);
String Date = jsonObject.getString("Date");
Log.d("Date: ",Date);
DatabaseHandler db=new DatabaseHandler(context);
db.addnotification(new notification(alert,Message,Date));
Log.d("Reading: ", "Reading all notifications..");
List<notification> notifications = db.getAllnotifications();
for (notification cn : notifications)
String log = "Id: "+cn.getID()+" ,Title: " + cn.gettitle() + " ,Message: " + cn.getmessage()+ " ,Date: " + cn.gettimedate();
// Writing notifications to log
Log.d("Name: ", log);
catch (JSONException e)
e.printStackTrace();
【问题讨论】：
您能否正确地提供一些关于您想要实现的目标的见解？您面临的任何错误和问题都可以帮助社区了解您实际遇到的问题 我想在列表视图中显示存储在sqlite中的json数据（其中“警报”“消息”“日期”） @F***o Francesconi 你可以从数据库中取回来，然后显示出来。你在寻找什么问题？ 如何找回它...@Diyoda 【参考方案1】：进行中,,,
-
编写您的 Dao 类（在您的情况下为 DatabaseHandler 类）以从数据库中获取数据（或者您可以编写一个内容提供程序 - 实现此目的的好方法。）
一个示例dao类如下，
public class DocumentRepository
public static final String TABLE_DOCUMENT = "document";
public static final String COLUMN_ID = BaseColumns._ID;
public static final String RECORD_ID = "record_id";
public static final String UUID_DOCUMENT_NAME = "unique_file_name";
public static final String DOCUMENT_TABLE_CREATE = "create table if not exists "
+ TABLE_DOCUMENT + "(" + COLUMN_ID
+ " integer primary key autoincrement, " + RECORD_ID
+ " integer , " + UUID_DOCUMENT_NAME
+ " text );";
private Context context;
public DocumentRepository(Context context)
this.context = context;
public ArrayList<Document> geDocuments(Integer customerId)
ArrayList<Document> documents = new ArrayList<>();
String query = "SELECT * FROM " + TABLE_DOCUMENT + " WHERE " + RECORD_ID + " = '" + customerId + "'";
SQLiteDatabase database = ......// create a instance of your SqliteDatabase implementation
Cursor cursor = database.rawQuery(query, null);
if (cursor.moveToFirst())
do
Document document = new Document();
document.setId(cursor.getInt(0));
document.setUniqueIdentifier(cursor.getString(3));
documents.add(document);
while (cursor.moveToNext());
return documents;
-
获取要在 ListView 中显示的对象列表。
在此示例中，geDocuments() 将为您提供对象列表。
-
将其注入您的 Adapter 并为 listView 引用设置 Adapter。
【讨论】：
【参考方案2】：公共类 DatabaseHandler 扩展 SQLiteOpenHelper
// All Static variables
// Database Version
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "notificationsbase";
// notifications table name
private static final String TABLE_notifications = "notifications";
// notifications Table Columns names
private static final String KEY_ID = "id";
private static final String KEY_title = "title";
private static final String KEY_message = "message";
private static final String KEY_timedate = "timedate";
public DatabaseHandler(Context context)
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db)
String CREATE_notificationS_TABLE = "CREATE TABLE " + TABLE_notifications + "("
+ KEY_ID + " INTEGER PRIMARY KEY," + KEY_title + " TEXT,"
+ KEY_message + " TEXT ," + KEY_timedate + " NUMERIC " + ")";
db.execSQL(CREATE_notificationS_TABLE);
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_notifications);
// Create tables again
onCreate(db);
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Adding new notification
void addnotification(notification notification)
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_title, notification.gettitle()); // title
values.put(KEY_message, notification.getmessage()); // message
values.put(KEY_timedate, notification.gettimedate()); // timedate
// Inserting Row
db.insert(TABLE_notifications, null, values);
db.close(); // Closing database connection
// Getting single notification
notification getContact(int id)
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_notifications, new String[] KEY_ID,
KEY_title, KEY_message, KEY_timedate , KEY_ID + "=?",
new String[] String.valueOf(id) , null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
notification notifications = new notification(Integer.parseInt(cursor.getString(0)),
cursor.getString(1), cursor.getString(2), cursor.getString(3));
// return contact
return notifications;
// Getting All notifications
public List<notification> getAllnotifications()
List<notification> notificationList = new ArrayList<notification>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_notifications;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst())
do
notification notification = new notification();
notification.setID(Integer.parseInt(cursor.getString(0)));
notification.settitle(cursor.getString(1));
notification.setmessage(cursor.getString(2));
notification.settimedate(cursor.getString(3));
// Adding notification to list
notificationList.add(notification);
while (cursor.moveToNext());
// return notification list
return notificationList;
// Updating single notification
public int updatenotification(notification notification)
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_title, notification.gettitle());
values.put(KEY_message, notification.getmessage());
values.put(KEY_timedate, notification.gettimedate());
// updating row
return db.update(TABLE_notifications, values, KEY_ID + " = ?",
new String[] String.valueOf(notification.getID()) );
// Deleting single notification
public void deletenotification(notification notification)
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_notifications, KEY_ID + " = ?",
new String[] String.valueOf(notification.getID()) );
db.close();
// Getting notifications Count
public int getnotificationsCount()
String countQuery = "SELECT * FROM " + TABLE_notifications;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
cursor.close();
// return count
return cursor.getCount();
public void open()
// TODO Auto-generated method stub
【讨论】：
【参考方案3】：public class notification
//private variables
int id;
String title;
String message;
String timedate;
// Empty constructor
public notification()
// constructor
public notification(int id, String title, String message, String timedate)
this.id = id;
this.title = title;
this.message = message;
this.timedate = timedate;
// constructor
public notification(String title, String message, String timedate)
this.title = title;
this.message = message;
this.timedate = timedate;
// getting ID
public int getID()
return this.id;
// setting id
public void setID(int id)
this.id = id;
// getting title
public String gettitle()
return this.title;
// setting title
public void settitle(String title)
this.title = title;
// getting message
public String getmessage()
return this.message;
// setting message
public void setmessage(String message)
this.message = message;
// getting timedate
public String gettimedate()
return this.timedate;
// setting message
public void settimedate(String timedate)
this.timedate = timedate;
【讨论】：
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