How to auto fit (auto scale or Zoom) an image in webView of your Android App? – Android Studio code

This video shows the steps to auto fit/ auto scale an image file in the WebView widget of your Android App.

It uses below attributes in the settings of the WebView object to enable the auto-scaling:
webView.getSettings().setLoadWithOverviewMode(true);
webView.getSettings().setUseWideViewPort(true);

For testing purpose, it uses below image from the testing page of programmer world website: https://programmerworld.co/selenium-test-page/

https://i0.wp.com/programmerworld.co/wp-content/uploads/2023/05/flower.png?w=977&ssl=1

I hope you like this video. For any questions, suggestions or appreciation please contact us at: https://programmerworld.co/contact/ or email at: programmerworld1990@gmail.com

Complete source code and other details:

package com.programmerworld.autofitimageinwebview;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.webkit.WebView;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {
private EditText editText;
private WebView webView;

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

editText = findViewById(R.id.editText);
webView = findViewById(R.id.webView);
}

public void buttonWithAutoFit(View view){
webView.loadUrl(editText.getText().toString());

webView.getSettings().setLoadWithOverviewMode(true);
webView.getSettings().setUseWideViewPort(true);
}


public void buttonWithoutAutoFit(View view){
webView.loadUrl(editText.getText().toString());

webView.getSettings().setLoadWithOverviewMode(false);
webView.getSettings().setUseWideViewPort(false);
}
}

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

<uses-permission android:name="android.permission.INTERNET"/>

<application
android:allowBackup="true"
android:dataExtractionRules="@xml/data_extraction_rules"
android:fullBackupContent="@xml/backup_rules"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.AutoFitImageInWebView"
tools:targetApi="31">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />

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

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">

<EditText
android:id="@+id/editText"
android:layout_width="355dp"
android:layout_height="61dp"
android:layout_marginStart="28dp"
android:layout_marginTop="59dp"
android:ems="10"
android:hint="URL ..."
android:inputType="text"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />

<Button
android:id="@+id/button"
android:layout_width="134dp"
android:layout_height="64dp"
android:layout_marginStart="28dp"
android:layout_marginTop="20dp"
android:onClick="buttonWithAutoFit"
android:text="Show Auto Fit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/editText" />

<Button
android:id="@+id/button2"
android:layout_width="146dp"
android:layout_height="64dp"
android:layout_marginStart="60dp"
android:layout_marginTop="20dp"
android:onClick="buttonWithoutAutoFit"
android:text="Show without autofit"
app:layout_constraintStart_toEndOf="@+id/button"
app:layout_constraintTop_toBottomOf="@+id/editText" />

<WebView
android:id="@+id/webView"
android:layout_width="409dp"
android:layout_height="507dp"
android:layout_marginStart="1dp"
android:layout_marginTop="1dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button2" />
</androidx.constraintlayout.widget.ConstraintLayout>

Screenshots:

URL of the image used in this demo:

https://i0.wp.com/programmerworld.co/wp-content/uploads/2023/05/flower.png?w=977&ssl=1

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