Scroll View - scrollBy() and scrollTo()

The method scrollBy() and scrollTo() can be called t scroll a view, by the amount of pixels to scroll and specify the position to scroll.

package com.exercise.AndroidScrollBy;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ScrollView;

public class AndroidScrollByActivity extends Activity {
 
 Button buttonScrollUp, buttonScrollDown, buttonScrollToTop;
 ScrollView myView;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        buttonScrollUp = (Button)findViewById(R.id.scrollup);
        buttonScrollDown = (Button)findViewById(R.id.scrolldown);
        buttonScrollToTop = (Button)findViewById(R.id.scrolltotop);
     myView = (ScrollView)findViewById(R.id.myview);
     
     buttonScrollUp.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    myView.scrollBy(0, +20);
   }});
     
     buttonScrollDown.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    myView.scrollBy(0, -20);
   }});
     
     buttonScrollToTop.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    myView.scrollTo(0, 0);
   }});
    }
}

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<Button
    android:id="@+id/scrollup"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Scroll Up"
    />
<Button
    android:id="@+id/scrolldown"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Scroll Down"
    />
<Button
    android:id="@+id/scrolltotop"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Scroll To Top"
    />
<ScrollView
    android:id="@+id/myview"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<LinearLayout
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="#A0A0A0"
    >
<ImageView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:src="@drawable/icon"
    />
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:textSize="40dp"
    android:text="This\nView\nCan\nBe\nScroled\nBy Buttons!"
    />
<Button
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Dummy Button"
    />
<Button
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Dummy Button"
    />
<Button
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Dummy Button"
    />
</LinearLayout>
</ScrollView>
</LinearLayout>