由于Android 5.0大图标在通知中有背景颜色：

Since Android 5.0 large icons in notifications have color background:

有关小图标，这是通知强调色（ Notification.Builder.setColor（INT））。如何设置它大图标？它是实际的图像的一部分？如果是，又该圆的半径是什么？

For small icon, it is the accent color of notification (Notification.Builder.setColor(int)). How do I set it for large icon? Is it part of the actual image? If it is, what should the circle radius be?

推荐答案

是的，大图标的颜色是实际图像的一部分。棒棒糖上的大图标的尺寸 40x40dp 用光学视图填充整个图像。所以，你应该建立40x40dp的资产与20dp半径的圆。 您可以设置通知的大图标如下：

Yes, the color of the large icon is part of the actual image. The dimensions of the large icon on lollipop are 40x40dp with a optical view filling the entire image. So you should create an asset of 40x40dp with a circle of a 20dp radius. You can set the notification's large icon as follows:

NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(context)
    .setSmallIcon(R.drawable.notification_small_icon)
    .setLargeIcon(notificationLargeIconBitmap)
    .setContentTitle("Notification")
    .setContentText("Content text")
    .setColor(context.getResources().getColor(R.color.accent_color));

如果你需要的大图标是从绘制资源，你可以得到一个位图实例是这样的：

If you need the large icon to be from a drawable resource you can get a Bitmap instance like this:

Bitmap notificationLargeIconBitmap = BitmapFactory.decodeResource(
    context.getResources(), 
    R.drawable.notification_large_icon);

如果您希望您的通知被很好地与Android的previous版本显示（奇巧及以下），你应该有你的大图标的平方版本的尺寸 64x64dp 。

If you want your notification to be displayed nicely with previous versions of android (kitkat and below), you should have a squared version of your large icon with a dimension of 64x64dp.