listview hiển thị dữ liệu từ cơ sở dữ liệu trong android

Sử dụng các lớp học này, điều này có thể giúp ích cho bạn

để tạo cơ sở dữ liệu

package com.example.grapes;

import java.util.ArrayList;
import java.util.List;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseHandler extends SQLiteOpenHelper {

    // All Static variables
    // Database Version
    private static final int DATABASE_VERSION = 1;

    // Database Name
    private static final String DATABASE_NAME = "dataManager";

    // Contacts table name
    private static final String TABLE_DATAS = "datas";

    // Contacts Table Columns names
    private static final String KEY_ID = "id";
    private static final String KEY_ITEM = "item";
    private static final String KEY_COMMENT = "comment";
    private static final String KEY_DATE = "date";
    private static final String KEY_TIME = "time";

    public DatabaseHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    // Creating Tables
    @Override
    public void onCreate(SQLiteDatabase db) {
        String CREATE_DATAS_TABLE = "CREATE TABLE " + TABLE_DATAS + "("
                + KEY_ID + " INTEGER PRIMARY KEY," + KEY_ITEM + " TEXT,"
                + KEY_COMMENT + " TEXT," + KEY_DATE + " TEXT," + KEY_TIME + " TEXT" + ")";
        db.execSQL(CREATE_DATAS_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_DATAS);

        // Create tables again
        onCreate(db);
    }

    /**
     * All CRUD(Create, Read, Update, Delete) Operations
     */

    // Adding new contact
    void addData(Datas data) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ITEM, data.getItem()); // Contact Name
        values.put(KEY_COMMENT, data.getComment()); // Contact Phone
        values.put(KEY_DATE, data.getDate()); // Contact Name
        values.put(KEY_TIME, data.getTime()); // Contact Phone

        // Inserting Row
        db.insert(TABLE_DATAS, null, values);
        db.close(); // Closing database connection
    }

    // Getting single contact
    Datas getData(int id) {
        SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE_DATAS, new String[] { KEY_ID,
                KEY_ITEM, KEY_COMMENT, KEY_DATE, KEY_TIME}, KEY_ID + "=?",
                new String[] { String.valueOf(id) }, null, null, null, null);
        if (cursor != null)
            cursor.moveToFirst();

        Datas data = new Datas(Integer.parseInt(cursor.getString(0)),
                cursor.getString(1), cursor.getString(2),cursor.getString(3), cursor.getString(4));
        // return contact
        return data;
    }

 Datas getItemOnly(int id) {
        SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE_DATAS, new String[] { KEY_ID,
                KEY_ITEM, KEY_COMMENT, KEY_DATE, KEY_TIME}, KEY_ID + "=?",
                new String[] { String.valueOf(id) }, null, null, null, null);
        if (cursor != null)
            cursor.moveToFirst();

        Datas data = new Datas(Integer.parseInt(cursor.getString(0)),
                cursor.getString(1), cursor.getString(2),cursor.getString(3), cursor.getString(4));
        // return contact
        return data;
    }

    // Getting All Contacts
    public List<Datas> getAllDatas() {
        List<Datas> dataList = new ArrayList<Datas>();
        // Select All Query
        String selectQuery = "SELECT  * FROM " + TABLE_DATAS;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {
                Datas data = new Datas();
                data.setID(Integer.parseInt(cursor.getString(0)));
                data.setItem(cursor.getString(1));
                data.setComment(cursor.getString(2));
                data.setDate(cursor.getString(3));
                data.setTime(cursor.getString(4));
                // Adding contact to list
                dataList.add(data);
            } while (cursor.moveToNext());
        }

        // return contact list
        return dataList;
    }

    // Updating single contact
    public void updateDatas(int position, String value) {
        SQLiteDatabase db = this.getWritableDatabase();

        String update = "UPDATE datas SET comment = '"+ value +"' WHERE ID = " + position;
        db.execSQL(update);

    }

    // Deleting single contact
        public void deleteValues(int position) {
            SQLiteDatabase db = this.getWritableDatabase();
            position = position + 1;
            String id = String.valueOf(position);
            db.delete(TABLE_DATAS, KEY_ID + "="+id,null);
            //Updating table
            //Creating temporary table

            String CREATE_TABLE_COPY = "CREATE TABLE " + "COPIED_TABLE" + "("
                    + KEY_ID + " INTEGER PRIMARY KEY," + KEY_ITEM + " TEXT,"
                    + KEY_COMMENT + " TEXT," + KEY_DATE + " TEXT," + KEY_TIME + " TEXT" + ")";
            db.execSQL(CREATE_TABLE_COPY);
            // Copying necessary columns to new temporary table
            String db_insert_command;
            db_insert_command = "INSERT INTO COPIED_TABLE (" + KEY_ITEM +", " + KEY_COMMENT + ", " + KEY_DATE + ", " + KEY_TIME + ") SELECT " + KEY_ITEM +", " + KEY_COMMENT + ", " + KEY_DATE + ", " + KEY_TIME + " FROM "+ TABLE_DATAS;
            System.out.println(db_insert_command);
            db.execSQL(db_insert_command);
            //Dropping old table
            db.execSQL("DROP TABLE " + TABLE_DATAS);
            //Creating old table again
            String CREATE_TABLE = "CREATE TABLE " + TABLE_DATAS + "("
                    + KEY_ID + " INTEGER PRIMARY KEY," + KEY_ITEM + " TEXT,"
                    + KEY_COMMENT + " TEXT," + KEY_DATE + " TEXT," + KEY_TIME + " TEXT"  + ")";
            db.execSQL(CREATE_TABLE);
            //Copying all fields from temporary table to newly created old table
            db.execSQL("INSERT INTO " + TABLE_DATAS + " SELECT * FROM COPIED_TABLE");
            //Dropping temporary table
            db.execSQL("DROP TABLE COPIED_TABLE");
            db.close();
        }


    // Getting contacts Count
    public int getDatasCount() {
        String countQuery = "SELECT  * FROM " + TABLE_DATAS;
        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cursor = db.rawQuery(countQuery, null);
        //cursor.close();

        // return count
        return cursor.getCount();
    }

}

để quản lý dữ liệu, hãy sử dụng lớp này

package com.example.grapes;

public class Datas {

    //private variables
    int _id;
    String _item;
    String _comment;
    String _date;
    String _time;

    // Empty constructor
    public Datas(){

    }
    // constructor
    public Datas(int id, String item, String comment, String date, String time){
        this._id = id;
        this._item = item;
        this._comment = comment;
        this._date = date;
        this._time = time;
    }

    // constructor
    public Datas(String item, String comment, String date, String time){
        this._item = item;
        this._comment = comment;
        this._date = date;
        this._time = time;
    }
    // getting ID
    public int getID(){
        return this._id;
    }

    // setting id
    public void setID(int id){
        this._id = id;
    }

    // getting name
    public String getItem(){
        return this._item;
    }

    // setting name
    public void setItem(String item){
        this._item = item;
    }

    // getting phone number
    public String getComment(){
        return this._comment;
    }

    // setting phone number
    public void setComment(String comment){
        this._comment = comment;
    }

    // getting phone number
    public String getDate(){
        return this._date;
    }

    // setting phone number
    public void setDate(String date){
        this._date = date;
    }

    // getting phone number
    public String getTime(){
        return this._time;
    }

    // setting phone number
    public void setTime(String time){
        this._time = time;
    }
}

cho chế độ xem danh sách, hãy sử dụng cái này

package com.example.grapes;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import android.widget.Toast;

public class ListviewActivity extends ListActivity {

    AlertDialog.Builder alert;
    EditText input;
    private static final int TEXT_ID = 0;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list);


        input = new EditText(this);
        alert = new AlertDialog.Builder(this);

        final DatabaseHandler db = new DatabaseHandler(this);

        System.out.println("Entered ListViewActivity");

        ArrayList<HashMap<String, String>> Items = new ArrayList<HashMap<String, String>>();

        System.out.println("Arraylist hashmap declared");

        // Reading all values
        Log.d("Reading: ", "Reading all contacts..");
        List<Datas> data = db.getAllDatas();       

        for (Datas val : data) {

                // Writing values to map
            HashMap<String, String> map = new HashMap<String, String>();
            map.put("comment",val.getComment());
            map.put("date", val.getDate());
            map.put("time", val.getTime());
            map.put("item", val.getItem());


            Items.add(map);        
        }

     // Adding Items to ListView
        ListAdapter adapter = new SimpleAdapter(this, Items,
                R.layout.list_item,new String[] { "date", "time", "comment", "item" },
                new int[] {R.id.date, R.id.time, R.id.capacity, R.id.price });

            setListAdapter(adapter);

            // selecting single ListView item
             ListView lv = getListView();
            lv.setLongClickable(true);

            lv.setOnItemLongClickListener(new OnItemLongClickListener() {

                public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
                        final int pos, long id) {
                    // TODO Auto-generated method stub

//                    Log.v("long clicked","pos"+" "+pos);
                    alert.setTitle("Confirm Delete");
                    // set dialog message
                    alert
                        .setMessage("Do you want to DELETE this entry?")
                        .setCancelable(false)
                        .setPositiveButton("Do it!",new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,int id) {
                                // if this button is clicked, close
                                // current activity
                                db.deleteValues(pos);
                                Intent i = new Intent(getApplicationContext(), ListviewActivity.class);
                                startActivity(i);

                            }
                          })
                        .setNegativeButton("I need this",new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,int id) {
                                // if this button is clicked, just close
                                // the dialog box and do nothing
                                dialog.cancel();
                            }
                        });

                        // create alert dialog
                        AlertDialog alertDialog = alert.create();

                        // show it
                        alertDialog.show();

                    return true;
                }
            });

            lv.setOnItemClickListener(new OnItemClickListener() {
                @Override
                public void onItemClick(AdapterView<?> arg0, View arg1,
                        final int pos, long id) {
                    // TODO Auto-generated method stub

                    input.setId(TEXT_ID);

                    alert.setView(input);

//                    Log.v("long clicked","pos"+" "+pos);
                    alert.setTitle("Edit the Comment?");

                     String dat = ((TextView) arg1.findViewById(R.id.date)).getText().toString();
                     String tim = ((TextView) arg1.findViewById(R.id.time)).getText().toString();
                     String itm = ((TextView) arg1.findViewById(R.id.price)).getText().toString();

                    // set dialog message
                    alert
                        .setMessage("Edit Comment of " + itm + " on " + dat + " " + tim + " ?")
                        .setCancelable(false)
                        .setPositiveButton("Do it!",new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,int id) {
                                // if this button is clicked, close
                                // current activity

                                String value = input.getText().toString();
                                Log.d("User name: ",value);
                                //return;
                               // db.execSQL(TABLE_DATAS, KEY_COMMENT, KEY_ID + " = " + string, null);
                                db.updateDatas(pos+1, value);
                                Intent j = new Intent(getApplicationContext(), ListviewActivity.class);
                                startActivity(j);

                            }
                          })
                        .setNegativeButton("I need this",new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,int id) {
                                // if this button is clicked, just close
                                // the dialog box and do nothing
                                dialog.cancel();
                            }
                        });

                        // create alert dialog
                        AlertDialog alertDialog = alert.create();

                        // show it
                        alertDialog.show();

                }
                });
            }

    @Override
    public boolean onCreateOptionsMenu(Menu menu)
    {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.main_menu, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
        switch (item.getItemId())
        {
            case R.id.home:
                ListviewActivity.this.finish();
                return true;
            case R.id.about:
                 Toast.makeText(getApplicationContext(), "This is collection and is created by amdel corporation",
                         Toast.LENGTH_LONG).show();
                return true;
            case R.id.exit:
                finish();
                System.exit(0);
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
}

cho hoạt động chèn, hãy sử dụng cái này

 db.addData(new Datas(item, comment, date, time));

Để đọc tất cả các mục

for (Datas d : datas) {
    String log = "Id: "+d.getID()+" ,Item: " + d.getItem() + " ,Comment: " + d.getComment() + " ,Date: " + d.getDate() + ",Comment: " + d.getTime();
               // Writing Contacts to log
    Log.d("Item: ", log);
}

Để xóa khỏi chế độ xem danh sách

                public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
                        final int pos, long id) {
                    // TODO Auto-generated method stub

//                    Log.v("long clicked","pos"+" "+pos);
                    alert.setTitle("Confirm Delete");
                    // set dialog message
                    alert
                        .setMessage("Do you want to DELETE this entry?")
                        .setCancelable(false)
                        .setPositiveButton("Do it!",new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,int id) {
                                // if this button is clicked, close
                                // current activity
                                db.deleteValues(pos);
                                Intent i = new Intent(getApplicationContext(), ListviewActivity.class);
                                startActivity(i);

                            }
                          })
                        .setNegativeButton("I need this",new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,int id) {
                                // if this button is clicked, just close
                                // the dialog box and do nothing
                                dialog.cancel();
                            }
                        });

                        // create alert dialog
                        AlertDialog alertDialog = alert.create();

                        // show it
                        alertDialog.show();

                    return true;
                }