การแสดงรายการข้อมูลจาก SQLite แบบ Endless Scrolling

build.gradle (Module: app)

apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    defaultConfig {
        applicationId "com.phaisarn.myapplication"
        minSdkVersion 21
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation 'com.android.support:design:26.1.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

    implementation 'com.github.markomilos:paginate:0.5.1'
}

apply plugin: 'com.android.application'

android {

compileSdkVersion 26

defaultConfig {

applicationId "com.phaisarn.myapplication"

minSdkVersion 21

targetSdkVersion 26

versionCode 1

versionName "1.0"

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

}

buildTypes {

release {

minifyEnabled false

proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'

}

dependencies {

implementation fileTree(dir: 'libs', include: ['*.jar'])

implementation 'com.android.support:appcompat-v7:26.1.0'

implementation 'com.android.support.constraint:constraint-layout:1.1.3'

implementation 'com.android.support:design:26.1.0'

testImplementation 'junit:junit:4.12'

androidTestImplementation 'com.android.support.test:runner:1.0.2'

androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

implementation 'com.github.markomilos:paginate:0.5.1'

}

content_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#dfdfdf"
    android:paddingBottom="0dp"
    android:paddingLeft="0dp"
    android:paddingRight="0dp"
    android:paddingTop="0dp"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context=".MainActivity"
    tools:showIn="@layout/activity_main">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_margin="10dp"></android.support.v7.widget.RecyclerView>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#dfdfdf"

android:paddingBottom="0dp"

android:paddingLeft="0dp"

android:paddingRight="0dp"

android:paddingTop="0dp"

app:layout_behavior="@string/appbar_scrolling_view_behavior"

tools:context=".MainActivity"

tools:showIn="@layout/activity_main">

<android.support.v7.widget.RecyclerView

android:id="@+id/recycler_view"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:layout_margin="10dp"></android.support.v7.widget.RecyclerView>

</LinearLayout>

MainActivity.java

package com.phaisarn.myapplication;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Handler;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;

import com.paginate.Paginate;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    private RecyclerView mRcv;
    private LinearLayoutManager mLayoutMan;
    private ArrayList<RowItem> mItemArray;
    private CustomAdapter mAdapter;
    private boolean mIsLoading = false;
    private int mCreatedItems;

    private final int ITEMS_PER_PAGE = 5;
    private SQLiteHelper mSQLiteHelper;
    private SQLiteDatabase mDb;
    private int mTotalRows;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
        fab.hide();
    }

    @Override
    public void onStart() {
        super.onStart();

        mSQLiteHelper = SQLiteHelper.getInstance(getBaseContext());
        mDb = mSQLiteHelper.getReadableDatabase();
        String sql = "SELECT * FROM list LIMIT " + ITEMS_PER_PAGE;
        Cursor cursor = mDb.rawQuery(sql, null);

        mItemArray = new ArrayList<>();
        RowItem row;
        while (cursor.moveToNext()) {
            row = new RowItem();
            row.item = cursor.getString(1);
            mItemArray.add(row);
        }

        mRcv = (RecyclerView) findViewById(R.id.recycler_view);
        mAdapter = new CustomAdapter(this, mItemArray);
        mRcv.setAdapter(mAdapter);

        mLayoutMan = new LinearLayoutManager(this, RecyclerView.VERTICAL, false);
        mRcv.setLayoutManager(mLayoutMan);

        sql = "SELECT COUNT(*) FROM list";
        Cursor cursorCount = mDb.rawQuery(sql, null);
        cursorCount.moveToFirst();
        mTotalRows = cursorCount.getInt(0);
        cursorCount.close();

        onScrollRecyclerView();
    }

    private void onScrollRecyclerView() {
        Paginate.Callbacks callbacks = new Paginate.Callbacks() {
            @Override
            public boolean isLoading() {
                return mIsLoading;
            }

            @Override
            public boolean hasLoadedAllItems() {
                mCreatedItems = mLayoutMan.getItemCount();
                if (mCreatedItems >= mTotalRows) {
                    return true;
                } else {
                    return false;
                }
            }

            @Override
            public void onLoadMore() {
                mIsLoading = true;
                new Handler().postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        mCreatedItems = mLayoutMan.getItemCount();
                        int startPosition = mCreatedItems - 1;
                        String sql = "SELECT * FROM list LIMIT ?, ?";
                        String[] args = {startPosition + "", ITEMS_PER_PAGE + ""};
                        Cursor cursor = mDb.rawQuery(sql, args);

                        RowItem row;
                        while (cursor.moveToNext()) {
                            row = new RowItem();
                            row.item = cursor.getString(1);
                            mItemArray.add(row);
                        }

                        mAdapter.notifyItemRangeInserted(startPosition, ITEMS_PER_PAGE);
                        mIsLoading = false;
                    }
                }, 4000);
            }
        };

        Paginate.with(mRcv, callbacks)
                .addLoadingListItem(true)
                .build();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

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package com.phaisarn.myapplication;

import android.os.Bundle;

import android.support.design.widget.FloatingActionButton;

import android.support.design.widget.Snackbar;

import android.support.v7.app.AppCompatActivity;

import android.support.v7.widget.Toolbar;

import android.view.View;

import android.view.Menu;

import android.view.MenuItem;

import android.database.Cursor;

import android.database.sqlite.SQLiteDatabase;

import android.os.Handler;

import android.support.v7.widget.LinearLayoutManager;

import android.support.v7.widget.RecyclerView;

import com.paginate.Paginate;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

private RecyclerView mRcv;

private LinearLayoutManager mLayoutMan;

private ArrayList<RowItem> mItemArray;

private CustomAdapter mAdapter;

private boolean mIsLoading = false;

private int mCreatedItems;

private final int ITEMS_PER_PAGE = 5;

private SQLiteHelper mSQLiteHelper;

private SQLiteDatabase mDb;

private int mTotalRows;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);

setSupportActionBar(toolbar);

FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);

fab.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)

.setAction("Action", null).show();

}

});

fab.hide();

}

@Override

public void onStart() {

super.onStart();

mSQLiteHelper = SQLiteHelper.getInstance(getBaseContext());

mDb = mSQLiteHelper.getReadableDatabase();

String sql = "SELECT * FROM list LIMIT " + ITEMS_PER_PAGE;

Cursor cursor = mDb.rawQuery(sql, null);

mItemArray = new ArrayList<>();

RowItem row;

while (cursor.moveToNext()) {

row = new RowItem();

row.item = cursor.getString(1);

mItemArray.add(row);

}

mRcv = (RecyclerView) findViewById(R.id.recycler_view);

mAdapter = new CustomAdapter(this, mItemArray);

mRcv.setAdapter(mAdapter);

mLayoutMan = new LinearLayoutManager(this, RecyclerView.VERTICAL, false);

mRcv.setLayoutManager(mLayoutMan);

sql = "SELECT COUNT(*) FROM list";

Cursor cursorCount = mDb.rawQuery(sql, null);

cursorCount.moveToFirst();

mTotalRows = cursorCount.getInt(0);

cursorCount.close();

onScrollRecyclerView();

}

private void onScrollRecyclerView() {

Paginate.Callbacks callbacks = new Paginate.Callbacks() {

@Override

public boolean isLoading() {

return mIsLoading;

}

@Override

public boolean hasLoadedAllItems() {

mCreatedItems = mLayoutMan.getItemCount();

if (mCreatedItems >= mTotalRows) {

return true;

} else {

return false;

}

@Override

public void onLoadMore() {

mIsLoading = true;

new Handler().postDelayed(new Runnable() {

@Override

public void run() {

mCreatedItems = mLayoutMan.getItemCount();

int startPosition = mCreatedItems - 1;

String sql = "SELECT * FROM list LIMIT ?, ?";

String[] args = {startPosition + "", ITEMS_PER_PAGE + ""};

Cursor cursor = mDb.rawQuery(sql, args);

RowItem row;

while (cursor.moveToNext()) {

row = new RowItem();

row.item = cursor.getString(1);

mItemArray.add(row);

}

mAdapter.notifyItemRangeInserted(startPosition, ITEMS_PER_PAGE);

mIsLoading = false;

}

}, 4000);

}

};

Paginate.with(mRcv, callbacks)

.addLoadingListItem(true)

.build();

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

// Inflate the menu; this adds items to the action bar if it is present.

getMenuInflater().inflate(R.menu.menu_main, menu);

return true;

}

@Override

public boolean onOptionsItemSelected(MenuItem item) {

// Handle action bar item clicks here. The action bar will

// automatically handle clicks on the Home/Up button, so long

// as you specify a parent activity in AndroidManifest.xml.

int id = item.getItemId();

//noinspection SimplifiableIfStatement

if (id == R.id.action_settings) {

return true;

}

return super.onOptionsItemSelected(item);

}

layout/item_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="100dp"
    android:layout_marginBottom="8dp"
    android:background="#fff"
    android:orientation="horizontal">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_vertical"
        android:layout_marginLeft="20dp"
        android:src="@mipmap/ic_launcher" />

    <TextView
        android:id="@+id/text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_vertical"
        android:layout_marginLeft="20dp"
        android:textSize="24sp" />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="100dp"

android:layout_marginBottom="8dp"

android:background="#fff"

android:orientation="horizontal">

<ImageView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_vertical"

android:layout_marginLeft="20dp"

android:src="@mipmap/ic_launcher" />

<TextView

android:id="@+id/text_view"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_vertical"

android:layout_marginLeft="20dp"

android:textSize="24sp" />

</LinearLayout>

CustomAdapter.java

package com.phaisarn.myapplication;

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import java.util.ArrayList;

public class CustomAdapter extends RecyclerView.Adapter<CustomHolder> {

      private ArrayList<RowItem> mItems;
      private Context mContext;

      public CustomAdapter(Context context, ArrayList<RowItem> items) {
            mContext = context;
            mItems = items;
      }

      @Override
      public int getItemCount() {
            return mItems.size();
      }

      @Override
      public CustomHolder onCreateViewHolder(ViewGroup vg, int type) {
            final LayoutInflater inflater = LayoutInflater.from(mContext);
            View view = inflater.inflate(R.layout.item_layout, vg, false);
            final CustomHolder vHolder = new CustomHolder(view);

            view.setOnClickListener(new View.OnClickListener() {
                  @Override
                  public void onClick(View view) {
                        int pos = vHolder.getAdapterPosition();
                        if(pos != RecyclerView.NO_POSITION) {
                              //...
                        }
                  }
            });

            return vHolder;
      }

      @Override
      public void onBindViewHolder(CustomHolder vHolder, int position) {
            RowItem row = mItems.get(position);
            vHolder.textView.setText(row.item);
      }

}

package com.phaisarn.myapplication;

import android.content.Context;

import android.support.v7.widget.RecyclerView;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import java.util.ArrayList;

public class CustomAdapter extends RecyclerView.Adapter<CustomHolder> {

private ArrayList<RowItem> mItems;

private Context mContext;

public CustomAdapter(Context context, ArrayList<RowItem> items) {

mContext = context;

mItems = items;

}

@Override

public int getItemCount() {

return mItems.size();

}

@Override

public CustomHolder onCreateViewHolder(ViewGroup vg, int type) {

final LayoutInflater inflater = LayoutInflater.from(mContext);

View view = inflater.inflate(R.layout.item_layout, vg, false);

final CustomHolder vHolder = new CustomHolder(view);

view.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

int pos = vHolder.getAdapterPosition();

if(pos != RecyclerView.NO_POSITION) {

//...

}

});

return vHolder;

}

@Override

public void onBindViewHolder(CustomHolder vHolder, int position) {

RowItem row = mItems.get(position);

vHolder.textView.setText(row.item);

}

CustomHolder.java

package com.phaisarn.myapplication;

import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.TextView;

public class CustomHolder extends RecyclerView.ViewHolder {
    public TextView textView;

    public CustomHolder(View view) {
        super(view);
        textView = (TextView) view.findViewById(R.id.text_view);
    }
}

package com.phaisarn.myapplication;

import android.support.v7.widget.RecyclerView;

import android.view.View;

import android.widget.TextView;

public class CustomHolder extends RecyclerView.ViewHolder {

public TextView textView;

public CustomHolder(View view) {

super(view);

textView = (TextView) view.findViewById(R.id.text_view);

}

RowItem.java

package com.phaisarn.myapplication;

public class RowItem {
    public int _id;
    public String item;
}

package com.phaisarn.myapplication;

public class RowItem {

public int _id;

public String item;

}

SQLiteHelper.java

package com.phaisarn.myapplication;

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

public class SQLiteHelper extends SQLiteOpenHelper {
    private static SQLiteHelper sqLiteDB;
    private static final String DB_NAME = "db_pagination";
    private static final int DB_VERSION = 1;

    private SQLiteHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    public static synchronized SQLiteHelper getInstance(Context context) {
        if (sqLiteDB == null) {
            sqLiteDB = new SQLiteHelper(context.getApplicationContext());
        }
        return sqLiteDB;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String sql =
                "CREATE TABLE IF NOT EXISTS list(" +
                        "_id INTEGER PRIMARY KEY AUTOINCREMENT, " +
                        "item TEXT)";
        db.execSQL(sql);

        for (int i = 1; i <= 50; i++) {
            sql = "INSERT INTO list(item) VALUES(?)";
            String[] args = {"Item " + i};
            db.execSQL(sql, args);
        }
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldV, int newV) {

    }

}

package com.phaisarn.myapplication;

import android.content.Context;

import android.database.sqlite.SQLiteDatabase;

import android.database.sqlite.SQLiteOpenHelper;

public class SQLiteHelper extends SQLiteOpenHelper {

private static SQLiteHelper sqLiteDB;

private static final String DB_NAME = "db_pagination";

private static final int DB_VERSION = 1;

private SQLiteHelper(Context context) {

super(context, DB_NAME, null, DB_VERSION);

}

public static synchronized SQLiteHelper getInstance(Context context) {

if (sqLiteDB == null) {

sqLiteDB = new SQLiteHelper(context.getApplicationContext());

}

return sqLiteDB;

}

@Override

public void onCreate(SQLiteDatabase db) {

String sql =

"CREATE TABLE IF NOT EXISTS list(" +

"_id INTEGER PRIMARY KEY AUTOINCREMENT, " +

"item TEXT)";

db.execSQL(sql);

for (int i = 1; i <= 50; i++) {

sql = "INSERT INTO list(item) VALUES(?)";

String[] args = {"Item " + i};

db.execSQL(sql, args);

}

@Override

public void onUpgrade(SQLiteDatabase db, int oldV, int newV) {

}

Phaisarn Sutheebanjard

blog.phaisarn.com

การแสดงรายการข้อมูลจาก SQLite แบบ Endless Scrolling