0

「To Do リスト」を作成しようとしていますが、データの保存以外はすべて完了しています。私はかなり新しいので、データを内部的に保存する方法を誰かに教えてもらえないかと思っています。

これが私のコードです：

Main_ToDoList.java

public class Main_ToDoList extends Activity implements OnClickListener
{
private Button btnAdd;
private EditText et;
private ListView lv;
ArrayList<String> list = new ArrayList<String>();
ArrayAdapter<String> adapter;

final Context context = this;

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main_activity);

    btnAdd = (Button)findViewById(R.id.addTaskBtn);
    btnAdd.setOnClickListener(this);
    et = (EditText)findViewById(R.id.editText);
    adapter = new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1, list);

    // set the lv variable to your list in the xml
    lv=(ListView)findViewById(R.id.list);
    lv.setAdapter(adapter);

    // set ListView item listener
    lv.setOnItemClickListener(new AdapterView.OnItemClickListener()
    {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, final int position, long id)
        {
            AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context);
            alertDialogBuilder.setTitle("Confirm Delete");
            alertDialogBuilder.setMessage("Sure you want to delete?");
            alertDialogBuilder.setCancelable(false);
            alertDialogBuilder.setPositiveButton("Yes", new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialogInterface, int i)
                {
                    adapter.remove(adapter.getItem(position));
                }
            });
            alertDialogBuilder.setNegativeButton("No", new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialogInterface, int i)
                {
                    dialogInterface.cancel();
                }
            });
            AlertDialog alertDialog = alertDialogBuilder.create();
            alertDialog.show();
        }
    });
}
public void onClick(View v)
{
    String input = et.getText().toString();
    if(input.length() > 0)
    {
        adapter.add(input);
        et.setText("");
    }
}
@Override
public boolean onCreateOptionsMenu(Menu menu)
{
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main__to_do_list, menu);
    return true;
} 
}

入力したデータを保存するにはどうすればよいですか? ありがとう！

4

3 に答える 3

0

1 つの DatabaseHandler クラスを作成できます

        package com.connection;

         import java.io.File;
         import java.io.FileOutputStream;
         import java.io.IOException;
         import java.io.InputStream;
         import java.io.OutputStream;
         import java.util.ArrayList;
         import android.content.ContentValues;
         import android.content.Context;
          import android.database.Cursor;
         import android.database.sqlite.SQLiteDatabase;
         import android.database.sqlite.SQLiteOpenHelper;
         import android.database.sqlite.SQLiteStatement;
            import android.util.Log;

        public class DatabaseHandler extends SQLiteOpenHelper {



// ====================== String Variables ======================
// The Android's default system path of your application database.
private static String DB_PATH = "/data/data/com.example/databases/"; // Package name
private static final String DATABASE_NAME = "test"; // Database Name

// ++++++++++++++++++++++ int Variables ++++++++++++++++++++++
private static final int DATABASE_VERSION = 1; // Database Version

// = = = = = = = = = = = Other Variables = = = = = = = = = = ==
private SQLiteDatabase myDataBase;
private final Context myContext;
SQLiteDatabase db;





public DatabaseHandler(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
    this.myContext = context;



}
public void db_open()
{
    db = this.getWritableDatabase();
}
/**
 * Creates a empty database on the system and rewrites it with your own
 * database.
 * */
public void createDataBase() throws IOException {
    boolean dbExist = databaseExist();

    if (dbExist) {
        // do nothing - database already exist
    } else {
        // By calling this method and empty database will be created into
        // the default system path
        // of your application so we are gone a be able to overwrite that
        // database with our database.
        this.getReadableDatabase();
        try {
            copyDataBase(); // call method to copy database
            db = this.getWritableDatabase();
        } catch (IOException e) {
            throw new Error("Error copying database");
        }
    }
}

/**
 * Mrthod to check database is exist or not
 * @return
 */
public boolean databaseExist()
{
    File dbFile = new File(DB_PATH + DATABASE_NAME);
    return dbFile.exists();
}

/**
 * Copies your database from your local assets-folder to the just created
 * empty database in the system folder, from where it can be accessed and
 * handled. This is done by transfering bytestream.
 * */
private void copyDataBase() throws IOException {
    // Open your local db as the input stream
    InputStream myInput = myContext.getAssets().open(DATABASE_NAME);

    // Path to the just created empty db
    String outFileName = DB_PATH + DATABASE_NAME;

    // Open the empty db as the output stream
    OutputStream myOutput = new FileOutputStream(outFileName);

    // transfer bytes from the inputfile to the outputfile
    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer)) > 0) {
        myOutput.write(buffer, 0, length);
    }

    // Close the streams
    myOutput.flush();
    myOutput.close();
    myInput.close();

}


/**
 * Close Database
 */
@Override
public synchronized void close() {



    if (myDataBase != null)
        myDataBase.close();
    super.close();
}

public void DB_close()
{
    if(db!=null)
        db.close();
}


/**
 * Method to add data

 */
public  boolean addData(int vno,String content1,String content2){
    boolean status=false;

    ContentValues values = new ContentValues();
    String checkEntry = "select id from yourtable where id="+vno;// +"' AND userid="+userid;

    Cursor magazinecursor = db.rawQuery(checkEntry, null);
    if (magazinecursor.moveToFirst()) {

    } else {

        values.put("id", vno);
        values.put("content1", content1);
        values.put("content2", content2);




        long check = db.insert("yourtable", null, values);
        if (check > -1) {
            Log.i("inserstatus", "yourtable insert successfull");
            status = true;
        } else {
            Log.i("insertstatus", "yourtable insert unsuccessful");
        }
    }

    return status;
}





@Override
public void onCreate(SQLiteDatabase db) {

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

}

そして、データを保存したいアクティビティで

              DatabaseHandler myDbHelper;

            myDbHelper = new DatabaseHandler(MainActivity.this);
            myDbHelper.db_open();
            myDbHelper.addData(1,"sample",sample);

これがあなたや他の人に役立つことを願っています....

于 2013-09-09T12:43:31.667 に答える
0

似たようなことがありました。少量のデータを保存したかったのですが、コンテンツ プロバイダーやファイルを使用したくなかったので、SharePreferences を使用しました。（psキーの最後に乱数を使用して一意にしましたが、ユーザーが後でリストから選択したため、値がわかります）

SharedPreferences sp = this.getPreferences( Context.MODE_PRIVATE );
SharedPreferences.Editor editor = sp.edit();
Random rand = new Random();
int randomNum = rand.nextInt( 1000 );
editor.putString( "EQUATION_KEY_" + String.valueOf( randomNum ), textToSave);
editor.commit();
于 2013-09-09T12:19:01.830 に答える