How To Apply ImageLoader in Picasso

Posted By : Rahul Baboria | 29-Oct-2017

android

Introduction:

Android Picasso is an image loading library developed by Square Inc. Nowadays it is among most popular libraries for image caching and loading among glide, volley ,etc as it requires just one line of code . To use Picasso Library in your project add following dependency:

MAVEN:

<dependency>
  <groupId>com.squareup.picasso</groupId>
  <artifactId>picasso</artifactId>
  <version>2.5.2</version>
</dependency>

GRADLE:

compile 'com.squareup.picasso:picasso:2.5.2'

Its always been difficult to show progressbar with ImageView while loading image from internet by using image caching libraries but here we have to just pass the drawable file to placeholder . Lets take an example by creating a xml file for progress bar under src/res/drawables of your project with following code:

progress_bar_drawable.xml

<?xml version="1.0" encoding="utf-8"?>
<rotate  xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="2000"
    android:fromDegrees="0"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toDegrees="1080" >

    <shape
        android:innerRadius="17dp"
        android:shape="ring"
        android:thickness="3dp"
        android:useLevel="false" >

        <gradient
            android:centerColor="#80b7b4b2"
            android:centerY="0.5"
            android:endColor="#f4eef0"
            android:startColor="#00938c87"
            android:type="sweep"
            android:useLevel="false" />
    </shape>

</rotate>

After adding this file to your project we can show this loader rotating instead of blank interface which makes bad impression to user as user don't knows whats happening. So to show Progress (loader) we have to give placeholder location ex: progress_bar_drawable in .placeholder() in your code as shown below :

Picasso.with(activity)
.load(team.getImageUrl())
                    .placeholder(R.drawable.progress_bar_drawable) 
                    .error(R.drawable.error_drawable)

                    .into(iv_placeholder)

Thanks.