SVGImageView.java

/*
   Copyright 2013 Paul LeBeau, Cave Rock Software Ltd.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package com.xdroid.animation.anim.svg;

import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Method;

import android.content.Context;
import android.graphics.Paint;
import android.graphics.drawable.PictureDrawable;
import android.net.Uri;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;

/**
 * SVGImageView is a View widget that allows users to include SVG images in their layouts.
 * <p/>
 * It is implemented as a thin layer over {@code android.widget.ImageView}.
 * <p/>
 * In its present form it has one significant limitation.  It uses the {@link SVG#renderToPicture()}
 * method. That means that SVG documents that use {@code <mask>} elements will not display correctly.
 *
 * @attr ref R.styleable#SVGImageView_svg
 */
public class SVGImageView extends ImageView {
    private static Method setLayerTypeMethod = null;

    {
        try {
            setLayerTypeMethod = View.class.getMethod("setLayerType", Integer.TYPE, Paint.class);
        } catch (NoSuchMethodException e) { /* do nothing */ }
    }


    public SVGImageView(Context context) {
        super(context);
    }


    public SVGImageView(Context context, AttributeSet attrs) {
        super(context, attrs, 0);
        init(attrs, 0);
    }


    public SVGImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(attrs, defStyle);
    }


    private void init(AttributeSet attrs, int defStyle) {
        /*TypedArray a = getContext().getTheme()
                .obtainStyledAttributes(attrs, R.styleable.SVGImageView, defStyle, 0);
        try {
            int resourceId = a.getResourceId(R.styleable.SVGImageView_svg, -1);
            if (resourceId != -1) {
                setImageResource(resourceId);
                return;
            }

            String url = a.getString(R.styleable.SVGImageView_svg);
            Uri uri = url != null ? Uri.parse(url) : null;
            if (internalSetImageURI(uri))
                return;

            // Last chance, try loading it as an asset filename
            setImageAsset(url);

        } finally {
            a.recycle();
        }*/
    }


    /**
     * Load an SVG image from the given resource id.
     */
    @Override
    public void setImageResource(int resourceId) {
        try {
            SVG svg = SVG.getFromResource(getContext(), resourceId);
            setSoftwareLayerType();
            setImageDrawable(new PictureDrawable(svg.renderToPicture()));
        } catch (SVGParseException e) {
            Log.w("SVGImageView", "Unable to find resource: " + resourceId, e);
        }
    }


    /**
     * Load an SVG image from the given resource URI.
     */
    @Override
    public void setImageURI(Uri uri) {
        internalSetImageURI(uri);
    }


    /**
     * Load an SVG image from the given asset filename.
     */
    public void setImageAsset(String filename) {
        try {
            SVG svg = SVG.getFromAsset(getContext().getAssets(), filename);
            setSoftwareLayerType();
            setImageDrawable(new PictureDrawable(svg.renderToPicture()));
        } catch (Exception e) {
            Log.w("SVGImageView", "Unable to find asset file: " + filename, e);
        }
    }

    public void setImageFile(String filename) {
        try {
            SVG svg = SVG.getFromFile(getContext(), filename);
            setSoftwareLayerType();
            setImageDrawable(new PictureDrawable(svg.renderToPicture()));
        } catch (Exception e) {
            Log.w("SVGImageView", "Unable to find asset file: " + filename, e);
        }
    }


    /*
     * Attempt to set a picture from a Uri. Return true if it worked.
     */
    private boolean internalSetImageURI(Uri uri) {
        InputStream is = null;
        try {
            is = getContext().getContentResolver().openInputStream(uri);
            SVG svg = SVG.getFromInputStream(is);
            setSoftwareLayerType();
            setImageDrawable(new PictureDrawable(svg.renderToPicture()));
            return true;
        } catch (Exception e) {
            Log.w("ImageView", "Unable to open content: " + uri, e);
            return false;
        } finally {
            try {
                if (is != null)
                    is.close();
            } catch (IOException e) { /* do nothing */ }
        }
    }


    /*
     * Use reflection to call an API 11 method from this library (which is configured with a minSdkVersion of 8)
     */
    private void setSoftwareLayerType() {
        if (setLayerTypeMethod == null)
            return;

        try {
            setLayerTypeMethod.invoke(this, LAYER_TYPE_SOFTWARE, null);
        } catch (Exception e) {
            Log.w("SVGImageView", "Unexpected failure calling setLayerType", e);
        }
    }
}