Tuesday, January 7, 2014

GridView selected image zooming and swipe to next image

This example select any one image from GridView zooming selected image and swaipe to next image if tap to the selected image go back to the GridView.


activity_main.xml


<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/container"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <GridView
        android:id="@+id/gridView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:columnWidth="80dp"
        android:horizontalSpacing="10dp"
        android:numColumns="auto_fit"
        android:stretchMode="columnWidth"
        android:verticalSpacing="10dp" >
    </GridView>

    <ImageView
        android:id="@+id/expanded_image"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:contentDescription="@string/app_name"
        android:visibility="invisible" />

</FrameLayout>

grid_item.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="5dp" >

    <ImageView
        android:id="@+id/thumb"
        android:layout_width="72dp"
        android:layout_height="72dp"
        android:layout_centerHorizontal="true"
        android:contentDescription="@string/app_name" />

</RelativeLayout>


MainActivity.java


import android.os.Bundle;
import android.view.GestureDetector;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.DecelerateInterpolator;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.AnimatorSet;
import android.animation.ObjectAnimator;
import android.app.Activity;
import android.content.Context;
import android.graphics.Point;
import android.graphics.Rect;

public class MainActivity extends Activity {

private GridView gv;
private Animator mCurrentAnimator;
private int mShortAnimationDuration;
private int j = 0;
private final GestureDetector detector = new GestureDetector(new SwipeGestureDetector());
    private static final int SWIPE_MIN_DISTANCE = 120;
    private static final int SWIPE_THRESHOLD_VELOCITY = 200;

// Create Array thumbs resource id's:
private int thumb[] = { R.drawable.cupcake, R.drawable.donut,
R.drawable.eclair, R.drawable.froyo, R.drawable.gingerbread,
R.drawable.honeycomb, R.drawable.icecreamsandwich,
R.drawable.jellybean, R.drawable.cupcake, R.drawable.donut,
R.drawable.eclair, R.drawable.froyo, R.drawable.gingerbread,
R.drawable.honeycomb, R.drawable.icecreamsandwich,
R.drawable.jellybean };
private ImageView expandedImageView;

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

// Initialize the variables:
gv = (GridView) findViewById(R.id.gridView);

// Set an Adapter to the ListView
gv.setAdapter(new ImageAdapter(this));

// Set on item click listener to the ListView
gv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View v, int pos,
long id) {

// Display the zoomed in image in full screen
j = pos;
zoomImageFromThumb(v, thumb[pos]);

}
});

// Set the Animation time form the android defaults
mShortAnimationDuration = getResources().getInteger(
android.R.integer.config_shortAnimTime);

}

// Create an Adapter Class extending the BaseAdapter
class ImageAdapter extends BaseAdapter {

private LayoutInflater layoutInflater;

public ImageAdapter(MainActivity activity) {
// TODO Auto-generated constructor stub
layoutInflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public int getCount() {
// Set the count value to the total number of items in the Array
return thumb.length;
}

@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

// Inflate the item layout and set the views
View listItem = convertView;
int pos = position;
if (listItem == null) {
listItem = layoutInflater.inflate(R.layout.grid_item, null);
}

// Initialize the views in the layout
ImageView iv = (ImageView) listItem.findViewById(R.id.thumb);

// Set the views in the layout
iv.setBackgroundResource(thumb[pos]);

return listItem;
}

}

private void zoomImageFromThumb(final View thumbView, int imageResId) {
// If there's an animation in progress, cancel it immediately and
// proceed with this one.
if (mCurrentAnimator != null) {
mCurrentAnimator.cancel();
}

// Load the high-resolution "zoomed-in" image.
expandedImageView = (ImageView) findViewById(R.id.expanded_image);
expandedImageView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                if (detector.onTouchEvent(event))
                    return true;
                else
                    return false;
            }
        });
expandedImageView.setImageResource(imageResId);

// Calculate the starting and ending bounds for the zoomed-in image.
// This step
// involves lots of math. Yay, math.
final Rect startBounds = new Rect();
final Rect finalBounds = new Rect();
final Point globalOffset = new Point();

// The start bounds are the global visible rectangle of the thumbnail,
// and the
// final bounds are the global visible rectangle of the container view.
// Also
// set the container view's offset as the origin for the bounds, since
// that's
// the origin for the positioning animation properties (X, Y).
thumbView.getGlobalVisibleRect(startBounds);
findViewById(R.id.container).getGlobalVisibleRect(finalBounds,
globalOffset);
startBounds.offset(-globalOffset.x, -globalOffset.y);
finalBounds.offset(-globalOffset.x, -globalOffset.y);

// Adjust the start bounds to be the same aspect ratio as the final
// bounds using the
// "center crop" technique. This prevents undesirable stretching during
// the animation.
// Also calculate the start scaling factor (the end scaling factor is
// always 1.0).
float startScale;
if ((float) finalBounds.width() / finalBounds.height() > (float) startBounds
.width() / startBounds.height()) {
// Extend start bounds horizontally
startScale = (float) startBounds.height() / finalBounds.height();
float startWidth = startScale * finalBounds.width();
float deltaWidth = (startWidth - startBounds.width()) / 2;
startBounds.left -= deltaWidth;
startBounds.right += deltaWidth;
} else {
// Extend start bounds vertically
startScale = (float) startBounds.width() / finalBounds.width();
float startHeight = startScale * finalBounds.height();
float deltaHeight = (startHeight - startBounds.height()) / 2;
startBounds.top -= deltaHeight;
startBounds.bottom += deltaHeight;
}

// Hide the thumbnail and show the zoomed-in view. When the animation
// begins,
// it will position the zoomed-in view in the place of the thumbnail.
thumbView.setAlpha(0f);
expandedImageView.setVisibility(View.VISIBLE);

// Set the pivot point for SCALE_X and SCALE_Y transformations to the
// top-left corner of
// the zoomed-in view (the default is the center of the view).
expandedImageView.setPivotX(0f);
expandedImageView.setPivotY(0f);

// Construct and run the parallel animation of the four translation and
// scale properties
// (X, Y, SCALE_X, and SCALE_Y).
AnimatorSet set = new AnimatorSet();
set.play(
ObjectAnimator.ofFloat(expandedImageView, View.X,
startBounds.left, finalBounds.left))
.with(ObjectAnimator.ofFloat(expandedImageView, View.Y,
startBounds.top, finalBounds.top))
.with(ObjectAnimator.ofFloat(expandedImageView, View.SCALE_X,
startScale, 1f))
.with(ObjectAnimator.ofFloat(expandedImageView, View.SCALE_Y,
startScale, 1f));
set.setDuration(mShortAnimationDuration);
set.setInterpolator(new DecelerateInterpolator());
set.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
mCurrentAnimator = null;
}

@Override
public void onAnimationCancel(Animator animation) {
mCurrentAnimator = null;
}
});
set.start();
mCurrentAnimator = set;

// Upon clicking the zoomed-in image, it should zoom back down to the
// original bounds
// and show the thumbnail instead of the expanded image.
final float startScaleFinal = startScale;
expandedImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mCurrentAnimator != null) {
mCurrentAnimator.cancel();
}

// Animate the four positioning/sizing properties in parallel,
// back to their
// original values.
AnimatorSet set = new AnimatorSet();
set.play(
ObjectAnimator.ofFloat(expandedImageView, View.X,
startBounds.left))
.with(ObjectAnimator.ofFloat(expandedImageView, View.Y,
startBounds.top))
.with(ObjectAnimator.ofFloat(expandedImageView,
View.SCALE_X, startScaleFinal))
.with(ObjectAnimator.ofFloat(expandedImageView,
View.SCALE_Y, startScaleFinal));
set.setDuration(mShortAnimationDuration);
set.setInterpolator(new DecelerateInterpolator());
set.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
thumbView.setAlpha(1f);
expandedImageView.setVisibility(View.GONE);
mCurrentAnimator = null;
}

@Override
public void onAnimationCancel(Animator animation) {
thumbView.setAlpha(1f);
expandedImageView.setVisibility(View.GONE);
mCurrentAnimator = null;
}
});
set.start();
mCurrentAnimator = set;
}
});
}
private class SwipeGestureDetector extends GestureDetector.SimpleOnGestureListener {
        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            try {
                if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {

                   if(thumb.length>j)
                    {
                        j++;

                        if(j < thumb.length)
                        {                           
                        expandedImageView.setImageResource(thumb[j]);
                            return true;
                        }
                        else
                        {
                            j = 0;
                            expandedImageView.setImageResource(thumb[j]);
                            return true;
                        }

                    }
                }
                else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {


                    if(j>0)
                    {
                        j--;
                        expandedImageView.setImageResource(thumb[j]);
                        return true;

                    }
                    else
                    {
                    j = thumb.length-1;
                    expandedImageView.setImageResource(thumb[j]);
                        return true;
                    }
                }
            }
                catch (Exception e) {
                    e.printStackTrace();
                }
                return false;
        }
    }

}