java异步上传图片示例

final file imagefile = new file(getcachedir().getpath() + "/img/" + p.image);
image.setvisibility(view.gone);
view.findviewbyid(r.id.imageloading).setvisibility(view.visible);
(new asynctask<void, void, bitmap>() {
    @override
    protected bitmap doinbackground(void... params) {
        try {
            bitmap image;
            if (!imagefile.exists() || imagefile.length() == 0) {
                image = bitmapfactory.decodestream(new url(
                        "http://example.com/images/"
                                + p.image).openstream());
                image.compress(bitmap.compressformat.jpeg, 85,
                        new fileoutputstream(imagefile));
                image.recycle();
            }
            image = bitmapfactory.decodefile(imagefile.getpath(),
                bitmapoptions);
            return image;
        } catch (malformedurlexception ex) {
            // todo auto-generated catch block
            ex.printstacktrace();
            return null;
        } catch (ioexception ex) {
            // todo auto-generated catch block
            ex.printstacktrace();
            return null;
        }
    }

    @override
    protected void onpostexecute(bitmap image) {
        if (view.gettag() != p) // the view was recycled.
            return;
            view.findviewbyid(r.id.imageloading).setvisibility(
                view.gone);
        view.findviewbyid(r.id.image)
                .setvisibility(view.visible);
        ((imageview) view.findviewbyid(r.id.image))
                .setimagebitmap(image);
    }
}).execute();