GifImageView.java

package pl.droidsonroids.gif;

import android.annotation.TargetApi;
import android.content.ContentResolver;
import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.content.res.Resources;
import android.content.res.Resources.NotFoundException;
import android.net.Uri;
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)
     */
    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)
     */
    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)
     */
    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 ignored) {
            //ignored
        } catch (NotFoundException ignored) {
            //ignored
        }
        if (isSrc) {
            super.setImageResource(resId);
        } else {
            super.setBackgroundResource(resId);
        }
    }

    /**
     * Sets the content of this GifImageView to the specified Uri.
     * If uri destination is not a GIF then {@link ImageView#setImageURI(Uri)}
     * is called as fallback.
     * For supported URI schemes see: {@link ContentResolver#openAssetFileDescriptor(Uri,
     * String)}.
     * <code>file</code> scheme is always supported.
     *
     * @param uri The Uri of an image
     */
    @Override
    public void setImageURI(Uri uri) {
        GifDrawable gd = null;
        if (uri != null) {
            final String scheme = uri.getScheme();
            try {
                if (ContentResolver.SCHEME_FILE.equals(scheme)) {
                    gd = new GifDrawable(uri.getPath());
                } else {
                    AssetFileDescriptor afd = getContext().getContentResolver()
                            .openAssetFileDescriptor(uri, "r");
                    if (afd != null) {
                        try {
                            gd = new GifDrawable(afd);
                        } catch (IOException ex) {
                            afd.close();
                        }
                    }
                }
            } catch (IOException ex) {
                //ignored
            }
        }
        if (gd != null) {
            setImageDrawable(gd);
        } else {
            super.setImageURI(uri);
        }
    }
}