MPChartExample/src/com/xxmassdeveloper/mpchartexample/RealmDatabaseActivity.java

package com.xxmassdeveloper.mpchartexample;

import android.graphics.Typeface;
import android.os.Bundle;
import android.view.WindowManager;

import com.github.mikephil.charting.animation.Easing;
import com.github.mikephil.charting.charts.LineChart;
import com.github.mikephil.charting.components.YAxis;
import com.github.mikephil.charting.data.LineData;
import com.github.mikephil.charting.data.realm.RealmLineDataSet;
import com.github.mikephil.charting.interfaces.datasets.ILineDataSet;
import com.xxmassdeveloper.mpchartexample.custom.RealmDemoData;
import com.xxmassdeveloper.mpchartexample.notimportant.DemoBase;

import java.util.ArrayList;

import io.realm.Realm;
import io.realm.RealmConfiguration;
import io.realm.RealmResults;

/**
 * Created by Philipp Jahoda on 21/10/15.
 */
public class RealmDatabaseActivity extends DemoBase {

    private LineChart mChart;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_linechart_noseekbar);

        mChart = (LineChart) findViewById(R.id.chart1);
        mChart.setDrawGridBackground(false);

        // no description text
        mChart.setDescription("");
        mChart.setNoDataTextDescription("You need to provide data for the chart.");

        // enable touch gestures
        mChart.setTouchEnabled(true);

        // enable scaling and dragging
        mChart.setDragEnabled(true);
        mChart.setScaleEnabled(true);

        // if disabled, scaling can be done on x- and y-axis separately
        mChart.setPinchZoom(false);

        Typeface tf = Typeface.createFromAsset(getAssets(), "OpenSans-Regular.ttf");

        YAxis leftAxis = mChart.getAxisLeft();
        leftAxis.removeAllLimitLines(); // reset all limit lines to avoid overlapping lines
        leftAxis.setAxisMaxValue(220f);
        leftAxis.setAxisMinValue(-50f);
        leftAxis.setStartAtZero(false);
        leftAxis.setTypeface(tf);

        mChart.getXAxis().setTypeface(tf);

        mChart.getAxisRight().setEnabled(false);

        // write some demo-data into the realm.io database
        writeToDB(400);

        // add data
        setData();

        mChart.animateY(1400, Easing.EasingOption.EaseInOutQuart);
    }

    private void writeToDB(int objectCount) {

        RealmConfiguration config = new RealmConfiguration.Builder(this)
                .name("myrealm.realm")
                .build();

        Realm.deleteRealm(config);

        Realm.setDefaultConfiguration(config);

        Realm realm = Realm.getInstance(config);

        realm.beginTransaction();

        realm.clear(RealmDemoData.class);

        for(int i = 0; i < objectCount; i++) {

            RealmDemoData d = new RealmDemoData(30f + (float) (Math.random() * 100.0), i);
            realm.copyToRealm(d);
        }

        realm.commitTransaction();
        realm.close();
    }

    private void setData() {

        RealmConfiguration config = new RealmConfiguration.Builder(this)
                .name("myrealm.realm")
                .build();

        Realm realm = Realm.getInstance(config);
        RealmResults<RealmDemoData> result = realm.allObjects(RealmDemoData.class);

        ArrayList<String> xVals = new ArrayList<String>();
        for (int i = 0; i < result.size(); i++) {
            xVals.add((i) + "");
        }

        RealmLineDataSet<RealmDemoData> set = new RealmLineDataSet<RealmDemoData>(result, "value", "xIndex");
        set.setValueTextSize(9f);

        ArrayList<ILineDataSet> dataSets = new ArrayList<ILineDataSet>();
        dataSets.add(set); // add the dataset

        // create a data object with the dataset list
        LineData data = new LineData(xVals, dataSets);

        // set data
        mChart.setData(data);

        realm.close();
    }
}