This library has copied from Jason Polites's gesture-imageview repository, fixed couple of bugs and merged with pull requests from other users.

This is a simple Android View class which provides basic pinch and zoom capability for images.

Can be used as a replacement for a standard ImageView when you want to include pinch and zoom.

Add dependency in your build.gradle

implementation 'com.cuneytayyildiz:gestureimageview:1.0.0'

1. Pinch zoom in place (i.e. zoom occurs from point of touch)
2. Panning with fling gesture
3. Double tap zoom
4. Configurable zoom boundaries (min/max)

1. Does not support Rotation
2. Does not support Pan and Zoom together
3. Not all methods of ImageView class are supported (will throw UnsupportedOperationException if strict is true)

1. Setting gesture-image:strict to true will result in UnsupportedOperationException if an unsupported method is called. Default value: false
2. Setting gesture-image:recycle to true will automatically reycle bitmap images when the view is destroyed. Default value: false

Configured as View in layout.xml

	<LinearLayout 
	    xmlns:android="http:https://schemas.android.com/apk/res/android"
	    xmlns:app="http:https://schemas.polites.com/android"
	    android:layout_width="fill_parent"
	    android:layout_height="fill_parent">

	    <com.cuneytayyildiz.gestureimageview.GestureImageView
	      android:id="@+id/image"
	      android:layout_width="fill_parent"
	    	android:layout_height="wrap_content" 
	    	android:src="@drawable/image"
	    	app:gi_min_scale="0.1"
	    	app:gi_max_scale="10.0"
	    	app:gi_strict="false"/>
	    	
	</LinearLayout>

Configured Programmatically

	import com.cuneytayyildiz.gestureimageview.GestureImageView;
	
	import android.app.Activity;
	import android.os.Bundle;
	import android.view.ViewGroup;
	import android.widget.LinearLayout.LayoutParams;
	
	public class SampleActivity extends AppCompatActivity {
	    @Override
	    public void onCreate(Bundle savedInstanceState) {
	        super.onCreate(savedInstanceState);
	        setContentView(R.layout.main);
	        
	        LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
	        
	        GestureImageView view = new GestureImageView(this);
	        view.setImageResource(R.drawable.image);
	        view.setLayoutParams(params);
	        
	        ViewGroup layout = (ViewGroup) findViewById(R.id.layout);
	
	        layout.addView(view);
	    }
	}