Hello Readers! In this post, we are going to learn about how to use android imageView widget in any android application. We will also go through different attributes of imageView widget that can be used to customise it.

Output

Tutorialwing Android ImageView Output

Getting Started

Android ImageView widget can be defined as below –

ImageView is subclass of View that displays image resource.

Attributes of Android ImageView Widget

Some of the popular attributes of android ImageView widget are –

Some of the popular attributes of ImageButton inherited from View are –

Example of Android ImageView Widget

At first, we will create android application. Then, we will use imageView widget in this application.

1. Creating New Project

Follow steps below to create new project. Please ignore the steps if you have already created a new application.

Now, we will modify xml and java file to use imageView widget in the application.

2. Modify Values folder

Open res/values/strings.xml file. Then, add below code into it.

<resources>
	<string name="app_name">ImageView</string>
	<string name="this_is_imageview">This is imageView</string>
	<string name="change_image">Change Image</string>
</resources>

3. Use ImageView Widget in xml file

Open res/layout/activity_main.xml file. Then, add below code into it.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
	xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:gravity="center"
	android:orientation="vertical">

	<Button
		android:id="@+id/button"
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:layout_marginBottom="20dp"
		android:text="@string/change_image"/>

	<ImageView
		android:id="@+id/imageView"
		android:layout_width="80dp"
		android:layout_height="80dp"
		android:contentDescription="@string/this_is_imageview"/>

</LinearLayout>

In activity_main.xml file, we have defined button and imageView widgets. Now, we will access this imageView widget in java file. Then, we will perform some operation on button click.

4. Access ImageView Widget in java file

Open src/main/java/com.tutorialwing.imageview/MainActivity.java file. Then, add below code into it.

package com.tutorialwing.imageview;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

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

		final ImageView imageView = findViewById(R.id.imageView);

		final Integer imgResId = R.drawable.ic_launcher_background;
		final Integer[] resId = {imgResId};
		imageView.setImageResource(imgResId);

		Button button = findViewById(R.id.button);
		if (button != null) {
			button.setOnClickListener(new View.OnClickListener() {
				@Override
				public void onClick(View v) {
					resId[0] = (resId[0] == R.drawable.ic_launcher_background) ? R.mipmap.ic_launcher : R.drawable.ic_launcher_background;
					imageView.setImageResource(resId[0]);
				}
			});
		}
	}
}

In MainActivity.java file, we have accessed imageView and button widgets. Then, we have set click listener on button to change image in imageView whenever button is clicked.

Since AndroidManifest.xml file is very important in any android application, we are also going to see the content inside this file.

AndroidManifest.xml

Code inside src/main/AndroidManifest.xml file is as below –

<?xml version="1.0" encoding="utf-8"?>
<manifest package="com.tutorialwing.imageview"
		  xmlns:android="http://schemas.android.com/apk/res/android">

	<application
		android:allowBackup="true"
		android:icon="@mipmap/ic_launcher"
		android:label="@string/app_name"
		android:roundIcon="@mipmap/ic_launcher_round"
		android:supportsRtl="true"
		android:theme="@style/AppTheme">
		<activity android:name=".MainActivity">
			<intent-filter>
				<action android:name="android.intent.action.MAIN"/>

				<category android:name="android.intent.category.LAUNCHER"/>
			</intent-filter>
		</activity>
	</application>

</manifest>

When we run the program, we will get output as shown above.

That’s end of tutorial on android imageView widget.