如何在Android中显示来自URL的图像

Question

我使用此代码从 url 显示图像，它可以工作，但图像存储在设备中，这是问题所在，因为我只想在用户连接到互联网时显示此图像

ImageView imageView=(ImageView) findViewById(R.id.imageView3);
image = BitmapFactory.decodeStream(url.openConnection().getInputStream());
imageView.setImageBitmap(bitmap);

如何在 Android 中显示来自 URL 的图像？

Answer 1

尝试这个解决方案..

image = BitmapFactory.decodeStream(url.openConnection().getInputStream());
imageView.setImageBitmap(image);

它会帮助你。

Answer 2

compile "com.squareup.picasso:picasso:2.4.0"

使用此库加载图像。

Picasso.with(context)
       .load(url)
       .placeholder(R.drawable.placeholder) //optional
       .resize(imgWidth, imgHeight)         //optional  
       .centerCrop()                        //optional   
       .into(image);                        //Your image view object.

Answer 3

要检查互联网连接，请使用以下代码

            ConnectivityManager connectivity = (ConnectivityManager) _Context
                .getSystemService(Context.CONNECTIVITY_SERVICE);

        if (connectivity != null) {
            NetworkInfo activeNetwork = connectivity.getActiveNetworkInfo();
            boolean isConnected = activeNetwork != null &&
                    activeNetwork.isConnectedOrConnecting();
            NetworkInfo[] info = connectivity.getAllNetworkInfo();
            if (info != null) {
                for (int i = 0; i < info.length; i++) {
                    if (info[i].getState() == NetworkInfo.State.CONNECTED) {
                        available = true;
                    }
                }
            }
        }
        if (available == false) {
            NetworkInfo wiMax = connectivity.getNetworkInfo(6);
            if (wiMax != null && wiMax.isConnected()) {
                available = true;
            }
        }

然后使用下载图像

class DownloadTask extends AsyncTask<String, Void, Bitmap> {
ImageView bmImage;
String image_name, studentName;
TextDrawable drawable;

public DownloadTask(ImageView bmImage, String file_name) {
    this.bmImage = bmImage;
    this.image_name = file_name;
}

protected Bitmap doInBackground(String... urls) {
    InputStream input = new java.net.URL(image_name).openStream();
    if(input.available()!=0) {
        return BitmapFactory.decodeStream(input);
    }
    return null;
}

protected void onPostExecute(Bitmap result) {
    try {
        if(result == null)
            bmImage.setImageDrawable(drawable);
        else
        bmImage.setImageBitmap(result);
    } catch (Exception e) {
        e.printStackTrace();
    }
}