Resize image to full width and fixed height with Picasso

You are looking for:

.fit().centerCrop()

What these mean:

• fit - wait until the ImageView has been measured and resize the image to exactly match its size.
• centerCrop - scale the image honoring the aspect ratio until it fills the size. Crop either the top and bottom or left and right so it matches the size exactly.

In some case the fit() is useless. Before you must wait for the width and height measurement to end. So you can use globallayoutlistener. for example;

imageView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
            public void onGlobalLayout() {
                Picasso.with(getActivity())
                        .load(imageUrl)
                        .placeholder(R.drawable.placeholder)
                        .error(R.drawable.error)
                        .resize(screenWidth, imageHeight)
                        .fit
                        .centerInside()
                        .into(imageView);
                imageView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
            }
        });