http://linroid.com/2016/11/25/Safety-after-invoke-Handler-removeCallbacks/

SafetyUtils.java

import android.os.Handler;
import android.os.Looper;

/**
 * @author linroid <linroid@gmail.com>
 * @since 25/11/2016
 */
public class SafetyUtils {
    public static void removeCallbacks(final Handler handler, final Runnable callback) {
        if (handler.getLooper() == Looper.myLooper()) {
            handler.removeCallbacks(callback);
        } else {
            handler.post(new Runnable() {
                @Override
                public void run() {
                    handler.removeCallbacks(callback);
                }
            });
        }
    }

    public static void removeMessages(final Handler handler, final int what) {
        removeMessages(handler, what, null);
    }

    public static void removeMessages(final Handler handler, final int what, final Object obj) {
        if (handler.getLooper() == Looper.myLooper()) {
            handler.removeMessages(what, obj);
        } else {
            handler.post(new Runnable() {
                @Override
                public void run() {
                    handler.removeMessages(what, obj);
                }
            });
        }
    }
}