andorid 配置器组件和提示消息

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.hanqi.application3.UIActivity7"
android:orientation="vertical">

<AutoCompleteTextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="自动完成文本编辑框"
android:id="@+id/actv_1"/>
<Spinner
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/sp_1">

</Spinner>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="状态栏提示"
android:onClick="notification_onClick"/>

</LinearLayout>

package com.hanqi.application3;

import android.app.Notification;
import android.app.NotificationManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.Spinner;
import android.widget.Toast;

public class UIActivity7 extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_ui7);

AutoCompleteTextView actv_1 = (AutoCompleteTextView)findViewById(R.id.actv_1);
//设置自动完成的数据源

String[] strings = {"China","Child","Chile","Chinese","Add","All","Class","Ddp"};
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this,R.layout.layout_array,strings);

actv_1.setAdapter(arrayAdapter);

//下拉列表
Spinner sp1= (Spinner)findViewById(R.id.sp_1);

sp1.setAdapter(arrayAdapter);

sp1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(UIActivity7.this, "position ="+position, Toast.LENGTH_SHORT).show();
}

@Override
public void onNothingSelected(AdapterView<?> parent) {

Toast.makeText(UIActivity7.this, "什么也没选", Toast.LENGTH_SHORT).show();

}
});
}
public void notification_onClick(View v)
{
//获取状态栏消息管理器
NotificationManager nm  = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);

//
Notification nt = new Notification.Builder(this)
.setContentTitle("这是一个通知")
.setContentText("这是通知内容：明天休息 ")
.setTicker("新通知")
.setSmallIcon(R.drawable.da1)
.setAutoCancel(true)
.setDefaults(Notification.DEFAULT_SOUND)

.build();
//交给管理器，发出消息
nm.notify(0,nt);

}
}

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="50dp"
android:textSize="30sp"
android:gravity="center_vertical"
android:paddingLeft="10dp">

</TextView>