NotificationManager

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

private NotificationManager manager;//通知控制类
private int Notification_ID;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);

FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});

findViewById(R.id.btn_send).setOnClickListener(this);
findViewById(R.id.btn_cancel).setOnClickListener(this);

manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();

//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}

return super.onOptionsItemSelected(item);
}

@Override
public void onClick(View v) {
switch(v.getId()){
case R.id.btn_send:{
sendNotification();
break;
}
case R.id.btn_cancel:{
cancelNotification();
break;
}
}
}

private void sendNotification(){
Intent intent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);
Notification.Builder builder = new Notification.Builder(this);
builder.setSmallIcon(R.drawable.x);
builder.setTicker("Hello");
builder.setWhen(System.currentTimeMillis());
builder.setContentTitle("通知栏通知 ");
builder.setContentText("我来自sendNotification");
builder.setContentIntent(pendingIntent);//点击后的意图
//        builder.setDefaults(Notification.DEFAULT_SOUND);//提示声音
//        builder.setDefaults(Notification.DEFAULT_LIGHTS);//提示指示灯
//        builder.setDefaults(Notification.DEFAULT_VIBRATE);//震动
builder.setDefaults(Notification.DEFAULT_ALL);//全部
Notification notification = builder.build();//4.1以上用着个

manager.notify(Notification_ID, notification);

}

private void cancelNotification(){
manager.cancel(Notification_ID);
}
}