Android | Seekbar

1. activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">

<SeekBar
android:id="@+id/sk"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_margin="20dp" />

</RelativeLayout>

2. MainActivity.java

package com.example.yt_seekbar;

import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.RelativeLayout;
import android.widget.SeekBar;

public class MainActivity extends AppCompatActivity {

SeekBar seekBar;
RelativeLayout relativeLayout;

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

seekBar = findViewById(R.id.sk);
relativeLayout = findViewById(R.id.container);

seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
if (progress > 50) {
relativeLayout.setBackgroundColor(Color.RED);
} else {
relativeLayout.setBackgroundColor(Color.YELLOW);
}
}

@Override
public void onStartTrackingTouch(SeekBar seekBar) {

}

@Override
public void onStopTrackingTouch(SeekBar seekBar) {

}
});
}
}

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