GifImageView.java

package python.gif;

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.Resources;
import android.content.res.Resources.NotFoundException;
import android.os.Build;
import android.util.AttributeSet;
import android.widget.ImageView;

import java.io.IOException;

/**
 * An {@link ImageView} which tries treating background and src as
 * {@link GifDrawable}
 * 
 * @author koral--
 */
public class GifImageView extends ImageView {
	static final String ANDROID_NS = "http://schemas.android.com/apk/res/android";

	/**
	 * A corresponding superclass constructor wrapper.
	 * 
	 * @see ImageView#ImageView(Context)
	 * @param context
	 */
	public GifImageView(Context context) {
		super(context);
	}

	/**
	 * Like eqivalent from superclass but also try to interpret src and
	 * background attributes as {@link GifDrawable}.
	 * 
	 * @see ImageView#ImageView(Context, AttributeSet)
	 * @param context
	 * @param attrs
	 */
	public GifImageView(Context context, AttributeSet attrs) {
		super(context, attrs);
		trySetGifDrawable(attrs, getResources());
	}

	/**
	 * Like eqivalent from superclass but also try to interpret src and
	 * background attributes as GIFs.
	 * 
	 * @see ImageView#ImageView(Context, AttributeSet, int)
	 * @param context
	 * @param attrs
	 * @param defStyle
	 */
	public GifImageView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		trySetGifDrawable(attrs, getResources());
	}

	@Override
	public void setImageResource(int resId) {
		setResource(true, resId, getResources());
	}

	@Override
	public void setBackgroundResource(int resId) {
		setResource(false, resId, getResources());
	}

	void trySetGifDrawable(AttributeSet attrs, Resources res) {
		if (attrs != null && res != null && !isInEditMode()) {
			int resId = attrs.getAttributeResourceValue(ANDROID_NS, "src", -1);
			if (resId > 0 && "drawable".equals(res.getResourceTypeName(resId)))
				setResource(true, resId, res);

			resId = attrs.getAttributeResourceValue(ANDROID_NS, "background",
					-1);
			if (resId > 0 && "drawable".equals(res.getResourceTypeName(resId)))
				setResource(false, resId, res);
		}
	}

	@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
	@SuppressWarnings("deprecation")
	// new method not avalilable on older API levels
	void setResource(boolean isSrc, int resId, Resources res) {
		try {
			GifDrawable d = new GifDrawable(res, resId);
			if (isSrc)
				setImageDrawable(d);
			else if (Build.VERSION.SDK_INT >= 16)
				setBackground(d);
			else
				setBackgroundDrawable(d);
			return;
		} catch (IOException e) {
			// ignored
		} catch (NotFoundException e) {
			// ignored
		}
		if (isSrc)
			super.setImageResource(resId);
		else
			super.setBackgroundResource(resId);
	}
}