posted 5 years ago
by AndroidBegin

12 Sep, 2013
12

Android Jake Wharton ViewPager Indicator Tutorial

In this tutorial, you will learn how to implement Jake Wharton’s viewpager indicator in your Android application. ViewPager indicator allows you provide a clear indicator that there exists additional content which they can click or swipe. We will create a viewpager and on flip left or right will show different images and texts and an indicator at the bottom view. So lets begin…

Download Jake Wharton’s ViewPagerIndicator Library

Visit Jake Wharton’s ViewPagerIndicator website and download the Zip file provided. The extracted zip folder should contain the files shown below.

Rename the folder “library” to “ViewPagerIndicatorLibrary” and copy the folder into your workspace as shown on the screenshot below.

Import ViewPagerIndicator Library

To import ViewPagerIndicator Library into Eclipse, go to File > Import > Select Existing Android Code into Workspace.

Click on Browse button and locate ViewPagerIndicator Library in your workspace. Import ViewPagerIndicator Library into your workspace by ticking the check box as shown on the screenshot below.

Implement ViewPagerIndicator Library into Project

Create a new project in Eclipse File > New > Android Application Project. Fill in the details and name your project ViewPagerTutorial.

Application Name : ViewPagerTutorial

Project Name : ViewPagerTutorial

Package Name : com.androidbegin.viewpagertutorial

Next, import ViewPagerIndicator Library into your project. Go to your project properties by right clicking on your project > Properties> Android > Add > Select ViewPagerIndicatorLibrary > Apply > OK.

Open your MainActivity.java and paste the following code.

MainActivity.java

package com.androidbegin.viewpagerindicatortutorial;

import android.os.Bundle;

import android.app.Activity;

import android.support.v4.view.PagerAdapter;

import android.support.v4.view.ViewPager;

import com.viewpagerindicator.UnderlinePageIndicator;

public class MainActivity extends Activity {

// Declare Variables

ViewPager viewPager;

PagerAdapter adapter;

String[] rank;

String[] country;

String[] population;

int[] flag;

UnderlinePageIndicator mIndicator;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

// Get the view from viewpager_main.xml

setContentView(R.layout.viewpager_main);

// Generate sample data

rank = new String[] { "1", "2", "3", "4", "5", "6", "7", "8", "9", "10" };

country = new String[] { "China", "India", "United States",

"Indonesia", "Brazil", "Pakistan", "Nigeria", "Bangladesh",

"Russia", "Japan" };

population = new String[] { "1,354,040,000", "1,210,193,422",

"315,761,000", "237,641,326", "193,946,886", "182,912,000",

"170,901,000", "152,518,015", "143,369,806", "127,360,000" };

flag = new int[] { R.drawable.china, R.drawable.india,

R.drawable.unitedstates, R.drawable.indonesia,

R.drawable.brazil, R.drawable.pakistan, R.drawable.nigeria,

R.drawable.bangladesh, R.drawable.russia, R.drawable.japan };

// Locate the ViewPager in viewpager_main.xml

viewPager = (ViewPager) findViewById(R.id.pager);

// Pass results to ViewPagerAdapter Class

adapter = new ViewPagerAdapter(MainActivity.this, rank, country,

population, flag);

// Binds the Adapter to the ViewPager

viewPager.setAdapter(adapter);

// ViewPager Indicator

mIndicator = (UnderlinePageIndicator) findViewById(R.id.indicator);

mIndicator.setFades(false);

mIndicator.setViewPager(viewPager);

}

In this activity, we have created string arrays with sample data and pass it into the ViewPagerAdapter class. In this tutorial, we are using an underline page indicator and disabled the indicator from fading.

We have prepared some sample images for this tutorial. Insert your downloaded sample images into your res > drawable-hdpi.

Sample Images

Flag (16.7 KiB, 9056 downloads)

Next, create an XML graphical layout for your MainActivity. Go to res > layout > Right Click on layout > New > Android XML File

Name your new XML file viewpager_main.xml and paste the following code.

viewpager_main.xml

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

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

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical" >

<android.support.v4.view.ViewPager

android:id="@+id/pager"

android:layout_width="fill_parent"

android:layout_height="0dp"

android:layout_weight="1" />

<com.viewpagerindicator.UnderlinePageIndicator

android:id="@+id/indicator"

android:layout_width="fill_parent"

android:layout_height="5dp" />

</LinearLayout>

Next, create a custom viewpager adapter. Go to File > New > Class and name it ViewPagerAdapter.java. Select your package named com.androidbegin.viewpagerindicatortutorial and click Finish.

Open your ViewPagerAdapter.java and paste the following code.

ViewPagerAdapter.java

package com.androidbegin.viewpagerindicatortutorial;

import android.content.Context;

import android.support.v4.view.PagerAdapter;

import android.support.v4.view.ViewPager;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.ImageView;

import android.widget.RelativeLayout;

import android.widget.TextView;

public class ViewPagerAdapter extends PagerAdapter {

// Declare Variables

Context context;

String[] rank;

String[] country;

String[] population;

int[] flag;

LayoutInflater inflater;

public ViewPagerAdapter(Context context, String[] rank, String[] country,

String[] population, int[] flag) {

this.context = context;

this.rank = rank;

this.country = country;

this.population = population;

this.flag = flag;

}

@Override

public int getCount() {

return rank.length;

}

@Override

public boolean isViewFromObject(View view, Object object) {

return view == ((RelativeLayout) object);

}

@Override

public Object instantiateItem(ViewGroup container, int position) {

// Declare Variables

TextView txtrank;

TextView txtcountry;

TextView txtpopulation;

ImageView imgflag;

inflater = (LayoutInflater) context

.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

View itemView = inflater.inflate(R.layout.viewpager_item, container,

false);

// Locate the TextViews in viewpager_item.xml

txtrank = (TextView) itemView.findViewById(R.id.rank);

txtcountry = (TextView) itemView.findViewById(R.id.country);

txtpopulation = (TextView) itemView.findViewById(R.id.population);

// Capture position and set to the TextViews

txtrank.setText(rank[position]);

txtcountry.setText(country[position]);

txtpopulation.setText(population[position]);

// Locate the ImageView in viewpager_item.xml

imgflag = (ImageView) itemView.findViewById(R.id.flag);

// Capture position and set to the ImageView

imgflag.setImageResource(flag[position]);

// Add viewpager_item.xml to ViewPager

((ViewPager) container).addView(itemView);

return itemView;

}

@Override

public void destroyItem(ViewGroup container, int position, Object object) {

// Remove viewpager_item.xml from ViewPager

((ViewPager) container).removeView((RelativeLayout) object);

}

In this custom viewpager adapter class, string arrays are passed into the ViewPagerAdapter and set into the TextViews and ImageViews followed by the positions.

Next, create an XML graphical layout for your listview item. Go to res > layout > Right Click on layout > New > Android XML File

Name your new XML file viewpager_item.xml and paste the following code.

viewpager_item.xml

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

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

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:gravity="center"

android:padding="10dp" >

<TextView

android:id="@+id/ranklabel"