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Android可从URL绘制图像

drawable image url android

Señor Reginold Francis · 技术社区 · 16 年前

我目前正在使用下面的代码将图像作为可绘制对象加载到URL中。

Drawable drawable_from_url(String url, String src_name) 
throws java.net.MalformedURLException, java.io.IOException {
        return Drawable.createFromStream(((java.io.InputStream)new java.net.URL(url).getContent()), src_name);

}

这段代码完全可以正常工作,但似乎存在兼容性问题。在版本1.5中,它抛出 FileNotFoundException

http://bks6.books.google.com/books?id=aH7BPTrwNXUC&printsec=frontcover&img=1&zoom=5&edge=curl&sig=ACfU3U2aQRnAX2o2ny2xFC1GmVn22almpg

5 回复 | 直到 11 年前

Joonsoo Cris 7 年前

public static Drawable drawableFromUrl(String url) throws IOException {
    Bitmap x;

    HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
    connection.connect();
    InputStream input = connection.getInputStream();

    x = BitmapFactory.decodeStream(input);
    return new BitmapDrawable(Resources.getSystem(), x);
}

(我使用了在 https://stackoverflow.com/a/2416360/450148 )

OneCricketeer Gabriele Mariotti 8 年前

我自己解决的。我使用下面的代码将其作为位图加载。

Bitmap drawable_from_url(String url) throws java.net.MalformedURLException, java.io.IOException {

    HttpURLConnection connection = (HttpURLConnection)new URL(url) .openConnection();
    connection.setRequestProperty("User-agent","Mozilla/4.0");

    connection.connect();
    InputStream input = connection.getInputStream();

    return BitmapFactory.decodeStream(input);
}

另外,添加用户代理也很重要,因为googlebooks拒绝用户代理的访问

Dan Lew 16 年前

我不确定,但我认为Drawable.createFromStream()更适合用于本地文件,而不是下载的InputStreams。尝试使用 BitmapFactory.decodeStream() BitmapDrawable .

Aziz Shaikh 13 年前

Matrix Mat = new Matrix();

Bitmap Source = BitmapFactory.decodeFile("ItemImagePath");

Bitmap Destination = Bitmap.createScaledBitmap( Source, 320, 320, true );

Source = Bitmap.createBitmap( Destination, 0, 0, Destination.getWidth(), Destination.getHeight(),Mat, true );

ItemImageView.setImageBitmap(Source);

Adriaan Koster 12 年前

您可以使用com.androidquery.androidquery非常简单地完成这项工作。例如:

AQuery aq = new AQuery(this);
aq.id(view).image("http://yourserver/yourimage.png", true, true, 300, new BitmapAjaxCallback() {
        @Override
        public void callback(String url, ImageView imageView, Bitmap bitmap, AjaxStatus status) {
            Drawable drawable = new BitmapDrawable(getResources(), bm);
        }
    });

如果使用BitmapAjaxCallback,则可以访问位图,该位图可以包装为BitmapDrawable。

Jorgesys 7 年前

AsyncTask 避免 NetWorkOnMainThreadException ,并在 onPostExecute() 您可以设置为ImageView:

    final String urlImage = "https://www.android.com/static/2016/img/hero-carousel/banner-android-p-2.jpg";

    new AsyncTask<String, Integer, Drawable>(){

        @Override
        protected Drawable doInBackground(String... strings) {
            Bitmap bmp = null;
            try {
                HttpURLConnection connection = (HttpURLConnection) new URL(urlImage).openConnection();
                connection.connect();
                InputStream input = connection.getInputStream();
                bmp = BitmapFactory.decodeStream(input);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return new BitmapDrawable(bmp);
        }

        protected void onPostExecute(Drawable result) {

            //Add image to ImageView
            myImageView.setImageDrawable(result);

        }


    }.execute();