问题
In my android application, i want to set Notification icons dynamically which will be loaded from URL. For that, i have used setLargeIcon property of NotificationBuilder in receiver.I reffered many link and tried various solutions but couldn\'t get desired output. Though i downloaded that image from url and setting that bitmap in notification, it is not being displayed. Instead it displays the setSmallIcon image as large icon. I don\'t know where i am going wrong. Here i am posting my code. Please help me to solve this issue. Thank you.
Code:
@SuppressLint(\"NewApi\")
public class C2DMMessageReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (\"com.google.android.c2dm.intent.RECEIVE\".equals(action)) {
Log.e(\"C2DM\", \"received message\");
final String fullName = intent.getStringExtra(\"message\");
final String payload1 = intent.getStringExtra(\"message1\");
final String payload2 = intent.getStringExtra(\"message2\");
final String userImage = intent.getStringExtra(\"userImage\");
Log.e(\"userImage Url :\", userImage); //it shows correct url
new sendNotification(context)
.execute(fullName, payload1, userImage);
}
}
private class sendNotification extends AsyncTask<String, Void, Bitmap> {
Context ctx;
String message;
public sendNotification(Context context) {
super();
this.ctx = context;
}
@Override
protected Bitmap doInBackground(String... params) {
InputStream in;
message = params[0] + params[1];
try {
in = new URL(params[2]).openStream();
Bitmap bmp = BitmapFactory.decodeStream(in);
return bmp;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
try {
NotificationManager notificationManager = (NotificationManager) ctx
.getSystemService(Context.NOTIFICATION_SERVICE);
Intent intent = new Intent(ctx, NotificationsActivity.class);
intent.putExtra(\"isFromBadge\", false);
Notification notification = new Notification.Builder(ctx)
.setContentTitle(
ctx.getResources().getString(R.string.app_name))
.setContentText(message)
.setSmallIcon(R.drawable.ic_launcher)
.setLargeIcon(result).build();
// hide the notification after its selected
notification.flags |= Notification.FLAG_AUTO_CANCEL;
notificationManager.notify(1, notification);
} catch (Exception e) {
e.printStackTrace();
}
}
}
回答1:
Changed my code as below and its working now :
private class sendNotification extends AsyncTask<String, Void, Bitmap> {
Context ctx;
String message;
public sendNotification(Context context) {
super();
this.ctx = context;
}
@Override
protected Bitmap doInBackground(String... params) {
InputStream in;
message = params[0] + params[1];
try {
URL url = new URL(params[2]);
HttpURLConnection connection = (HttpURLConnection)url.openConnection();
connection.setDoInput(true);
connection.connect();
in = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(in);
return myBitmap;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
try {
NotificationManager notificationManager = (NotificationManager) ctx
.getSystemService(Context.NOTIFICATION_SERVICE);
Intent intent = new Intent(ctx, NotificationsActivity.class);
intent.putExtra("isFromBadge", false);
Notification notification = new Notification.Builder(ctx)
.setContentTitle(
ctx.getResources().getString(R.string.app_name))
.setContentText(message)
.setSmallIcon(R.drawable.ic_launcher)
.setLargeIcon(result).build();
// hide the notification after its selected
notification.flags |= Notification.FLAG_AUTO_CANCEL;
notificationManager.notify(1, notification);
} catch (Exception e) {
e.printStackTrace();
}
}
}
回答2:
How to implement BigPicture style Notification:
Miracle has been done by .setStyle(new Notification.BigPictureStyle().bigPicture(result)) :
I have done this way with:
Generate notification by AsyncTask:
new generatePictureStyleNotification(this,"Title", "Message",
"http://api.androidhive.info/images/sample.jpg").execute();
AsyncTask:
public class generatePictureStyleNotification extends AsyncTask<String, Void, Bitmap> {
private Context mContext;
private String title, message, imageUrl;
public generatePictureStyleNotification(Context context, String title, String message, String imageUrl) {
super();
this.mContext = context;
this.title = title;
this.message = message;
this.imageUrl = imageUrl;
}
@Override
protected Bitmap doInBackground(String... params) {
InputStream in;
try {
URL url = new URL(this.imageUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
in = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(in);
return myBitmap;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
@Override
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
Intent intent = new Intent(mContext, MyOpenableActivity.class);
intent.putExtra("key", "value");
PendingIntent pendingIntent = PendingIntent.getActivity(mContext, 100, intent, PendingIntent.FLAG_ONE_SHOT);
NotificationManager notificationManager = (NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE);
Notification notif = new Notification.Builder(mContext)
.setContentIntent(pendingIntent)
.setContentTitle(title)
.setContentText(message)
.setSmallIcon(R.mipmap.ic_launcher)
.setLargeIcon(result)
.setStyle(new Notification.BigPictureStyle().bigPicture(result))
.build();
notif.flags |= Notification.FLAG_AUTO_CANCEL;
notificationManager.notify(1, notif);
}
}
回答3:
you can do this using Glide like this:
val notificationBuilder = NotificationCompat.Builder(this, channelId)
.setSmallIcon(R.drawable.ic_message)
.setContentTitle("title")
.setContentText("text")
val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
val futureTarget = Glide.with(this)
.asBitmap()
.load(photoUrl)
.submit()
val bitmap = futureTarget.get()
notificationBuilder.setLargeIcon(bitmap)
Glide.with(this).clear(futureTarget)
notificationManager.notify(0, notificationBuilder.build())
回答4:
Since image is loaded from internet, it should be done async in a background thread. Either use async task or Glide (for efficient image loading).
To load image notification, you need to use "NotificationCompat.BigPictureStyle()". This requires a bitmap (which has to be extracted from image url)
Most of the API's and methods of Glide are now deprecated. Below is working with Glide 4.9 and upto Android 10.
// Load bitmap from image url on background thread and display image notification
private void getBitmapAsyncAndDoWork(String imageUrl) {
final Bitmap[] bitmap = {null};
Glide.with(getApplicationContext())
.asBitmap()
.load(imageUrl)
.into(new CustomTarget<Bitmap>() {
@Override
public void onResourceReady(@NonNull Bitmap resource, @Nullable Transition<? super Bitmap> transition) {
bitmap[0] = resource;
// TODO Do some work: pass this bitmap
displayImageNotification(bitmap[0]);
}
@Override
public void onLoadCleared(@Nullable Drawable placeholder) {
}
});
}
Display the image notification once, the bitmap is ready.
private void displayImageNotification(Bitmap bitmap) {
NotificationCompat.Builder builder = new NotificationCompat.Builder(getApplicationContext(), getChannelId());
builder
.setContentTitle(title)
.setContentText(subtext)
.setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_VIBRATE)
.setSmallIcon(SMALL_ICON)
.setPriority(NotificationCompat.PRIORITY_DEFAULT)
.setColor(getApplicationContext().getColor(color))
.setAutoCancel(true)
.setOngoing(false)
.setOnlyAlertOnce(true)
.setContentIntent(pendingIntent)
.setStyle(
new NotificationCompat.BigPictureStyle().bigPicture(bitmap))
.setPriority(Notification.PRIORITY_HIGH);
getManager().notify(tag, id, builder.build());
}
回答5:
I know a good answer has been given so let's see if we can make it easier to understand and implement.
---------------------Theory------------------------
The problem can be abstracted in two step solution namely
1) Get image from a URL
2) Decode image and pass to notification builder
1) Get image from a URLInputStream in = new URL("Img URL goes here eg. http://gg.com/profile.jpg").openStream();
2) Decode and pass to notification Bitmap bmp = null; #create a null bmp container that will be used to hold decoded img bmp = BitmapFactory.decodeStream(in); # save the image into container
Voila!
once you build the image and save it in the variable bmp, you can call it on notification builder
.setLargeIcon(bmp)
--------Implementation---------------
Android studio will encourage you to wrap your code with try catch so the end product will look like this.
Bitmap bmp = null;
try {
InputStream in = new URL("url goes here").openStream();
bmp = BitmapFactory.decodeStream(in);
} catch (IOException e) {
e.printStackTrace();
}
Once you have the bmp you can call it in notification builder as
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this, CHANNEL_ID)
.setSmallIcon(R.drawable.ic_launcher)
.setContentText("title")
.setContentText("text goes here")
.setLargeIcon(bmp)
.setAutoCancel(true);
回答6:
Using Picasso Library.
Target target = new Target() {
@Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
largeIcon=bitmap;
}
@Override
public void onBitmapFailed(Drawable errorDrawable) {
}
@Override
public void onPrepareLoad(Drawable placeHolderDrawable) {
}
};
Picasso.with(this).load("url").into(target);
NotificationCompat.Builder notificationBuilder =
new NotificationCompat.Builder(this, channelId)
.setSmallIcon(R.drawable.icon)
.setContentTitle(msg.getString("title"))
.setContentText(msg.getString("msg"))
.setAutoCancel(true)
.setSound(defaultSoundUri)
.setLargeIcon(largeIcon)
.setContentIntent(pendingIntent);
回答7:
Top answer in Kotlin and with Coroutines. This method applies the bitmap to the builder instead of a direct assignment, and of course if bitmap available. It's nice because if the url is wrong it will be caught in the try/catch.
fun applyImageUrl(
builder: NotificationCompat.Builder,
imageUrl: String
) = runBlocking {
val url = URL(imageUrl)
withContext(Dispatchers.IO) {
try {
val input = url.openStream()
BitmapFactory.decodeStream(input)
} catch (e: IOException) {
null
}
}?.let { bitmap ->
builder.setLargeIcon(bitmap)
}
}
来源：https://stackoverflow.com/questions/24840282/load-image-from-url-in-notification-android