Android：通知生成器：API19的setcolor方法的替代方法

Question

I need to set the color of notification. It works fine if minSdk is at least API Level 21 . Once I drop the minSdk, code (below) doesn't compile.

notification = builder.setContentTitle(MyApp.getAppContext().getResources().getString(R.string.notification_content_title))
                .setContentText(contentText)
                .setColor(color)
                .build();

I get the following error message once I downgrade MinSdk to API Level 19 :

Call requires API level 21 (current min is 19): android.app.Notification.Builder#setColor

What would be the workaround? I came across NotificationCompact, should I switch to it?

Answer 1

I would recommend using NotificationCompat.Builder (from support library) instead of Notification.Builder .

To do so you will need the support v4 library in your project. If you don't have it already add this line to the dependencies closure of your build.gradle file:

compile "com.android.support:support-v4:23.1.1"

Then you would use NotificationCompat.Builder to make your notification.

String title = MyApp.getAppContext().getResources()
                                   .getString(R.string.notification_content_title);
Notification notification = new NotificationCompat.Builder(context)
                 .setContentTitle(title)
                 .setContentText(contentText)
                 .setColor(color)
                 .build();

Note that NotificationCompat.Builder cannot not backport all the functionality into older versions of android. Most of it (like the color of the notification) will be ignored in older versions of android. NotificationCompat.Builder will just prevent the errors you are seeing.

Alternatively you could add a SDK check before setting the color, but that would be a more verbose approach to doing what NotificationCompat.Builder does for you:

String title = MyApp.getAppContext().getResources().getString(R.string.notification_content_title);
Notification.Builder builder = new Notification.Builder(context)
                 .setContentTitle(title)
                 .setContentText(contentText);
if (Build.VERSION.SDK_INT >= ApiHelper.VERSION_CODES.LOLLIPOP) {
  builder.setColor(color);
}
Notification notification = builder.build();