Cannot use yellow with Android Nougat notification's small icon

Question

I've a problem setting the notification small icon to yellow in Android 7.x

I'm using notification.setColor(Color.YELLOW); while building the notification object. It shows that olive(ish) color instead of yellow.

Also tried to use notification.setColor(Color.argb(255,255,255,0)); but no luck, it shows the same olive(ish) color.

This is how it looks like in Android 7.x

This is how it looks like in Android 6.x, which is the correct color

Both images display the same notification with the same code base, but using different Android devices.

I'm using PushWoosh to send/receive push notifications, bellow is the exact code I'm using to create the notification object.

public class NotificationFactory extends AbsNotificationFactory {
@Override
public Notification onGenerateNotification(PushData pushData) {
    PushwooshUserdata pushwooshUserdata = GsonUtil.fromJson(pushData.getExtras().getString("u"), PushwooshUserdata.class);

    //create notification builder
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(getContext());
    notificationBuilder.setContentTitle("Header");
    notificationBuilder.setContentText("Message");

    //set small icon (usually app icon)
    notificationBuilder.setSmallIcon(R.drawable.notification_icon);
    notificationBuilder.setColor(Color.argb(255,255,255,0));

    //set ticket text
    notificationBuilder.setTicker(getContentFromHtml(pushData.getTicker()));

    //display notification now
    notificationBuilder.setWhen(System.currentTimeMillis());

    //build the notification
    final Notification notification = notificationBuilder.build();

    //add sound
    addSound(notification, pushData.getSound());

    //add vibration
    addVibration(notification, pushData.getVibration());

    //make it cancelable
    addCancel(notification);

    //all done!
    return notification;
}

@Override
public void onPushReceived(PushData pushData) {
}

@Override
public void onPushHandle(Activity activity) {
}
}

Answer 1

Android is ensuring a minimum contrast ratio between the foreground color and background color.

With the yellow (#ffff35) foreground and a white background, the contrast ratio is only 1.07:1.

The olive foreground (#717d13) has the minimum contrast ratio of 4.5:1.

This is the relevant patch in the Android source: https://android.googlesource.com/platform/frameworks/base.git/+/4ff3b120ff8a788e3afeb266d18caf072f0b8ffb%5E%21/

I calculated the above contrast ratios using http://webaim.org/resources/contrastchecker/.