【移動應用開發(fā)技術(shù)】Android版如何實現(xiàn)學生管理系統(tǒng)

【移動應用開發(fā)技術(shù)】Android版如何實現(xiàn)學生管理系統(tǒng)

<uses-permission

android:name="android.permission.READ_EXTERNAL_STORAGE"/>

<uses-permission

android:name="android.permission.WRITE_EXTERNAL_STORAGE"/><LinearLayout

xmlns:android="/apk/res/android"

xmlns:tools="/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="vertical"

>

<TextView

android:id="@+id/title"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_horizontal"

android:layout_marginTop="5dip"

android:textSize="28sp"

android:textColor="#D5F2F4"

android:text="學生管理系統(tǒng)"

/>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_marginTop="5dip"

android:orientation="horizontal">

<LinearLayout

android:layout_height="wrap_content"

android:layout_width="0dip"

android:layout_weight="1"

android:orientation="vertical">

<TextView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_horizontal"

android:textSize="18sp"

android:textColor="#DAD5D9"

android:text="姓名"/>

<EditText

android:id="@+id/et_name"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:singleLine="true"/>

</LinearLayout>

<LinearLayout

android:layout_height="wrap_content"

android:layout_width="0dip"

android:layout_weight="1"

android:orientation="vertical">

<TextView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_horizontal"

android:textSize="18sp"

android:textColor="#DAD5D9"

android:text="性別"/>

<EditText

android:id="@+id/et_sex"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:singleLine="true"/>

</LinearLayout>

<LinearLayout

android:layout_height="wrap_content"

android:layout_width="0dip"

android:layout_weight="1"

android:orientation="vertical">

<TextView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_horizontal"

android:textSize="18sp"

android:textColor="#DAD5D9"

android:text="年齡"/>

<EditText

android:id="@+id/et_age"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:inputType="number"

android:singleLine="true"/>

</LinearLayout>

<Button

android:id="@+id/btn_add"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="bottom"

android:textColor="@android:color/black"

android:textSize="20sp"

android:text="添加學生"/>

</LinearLayout>

<!--

ScrollView只可以包裹一個控件

-->

<ScrollView

android:layout_width="fill_parent"

android:layout_height="0dip"

android:layout_weight="1"

android:layout_marginTop="5dip">

<LinearLayout

android:id="@+id/ll_student_group"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical">

</LinearLayout>

</ScrollView>

<LinearLayout

android:orientation="horizontal"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_marginTop="5dip">

<Button

android:id="@+id/btn_save"

android:layout_width="0dip"

android:layout_height="fill_parent"

android:layout_weight="1"

android:textSize="20sp"

android:textColor="@android:color/black"

android:text="保存數(shù)據(jù)"/>

<Button

android:id="@+id/btn_restore"

android:layout_width="0dip"

android:layout_height="fill_parent"

android:layout_weight="1"

android:textSize="20sp"

android:textColor="@android:color/black"

android:text="恢復數(shù)據(jù)"/>

</LinearLayout>

</LinearLayout>/upload/information/20200623/125/124468.jpgpackage

cn.yzx.studentmanageros.domain;

public

class

Student

{

private

String

name;

private

String

sex;

private

Integer

age;

public

Student()

{

super();

//

TODO

Auto-generated

constructor

stub

}

public

Student(String

name,

String

sex,

Integer

age)

{

super();

=

name;

this.sex

=

sex;

this.age

=

age;

}

@Override

public

String

toString()

{

return

"Student

[name="

+

name

+

",

sex="

+

sex

+

",

age="

+

age

+

"]";

}

public

String

getName()

{

return

name;

}

public

void

setName(String

name)

{

=

name;

}

public

String

getSex()

{

return

sex;

}

public

void

setSex(String

sex)

{

this.sex

=

sex;

}

public

Integer

getAge()

{

return

age;

}

public

void

setAge(Integer

age)

{

this.age

=

age;

}

}package

cn.yzx.studentmanageros;

import

java.io.File;

import

java.io.FileInputStream;

import

java.io.FileNotFoundException;

import

java.io.FileOutputStream;

import

java.io.IOException;

import

java.text.Format;

import

java.util.ArrayList;

import

java.util.List;

import

org.xmlpull.v1.XmlPullParser;

import

org.xmlpull.v1.XmlPullParserException;

import

org.xmlpull.v1.XmlSerializer;

import

android.app.Activity;

import

android.graphics.Color;

import

android.os.Bundle;

import

android.os.Environment;

import

android.text.TextUtils;

import

android.util.Log;

import

android.util.Xml;

import

android.view.View;

import

android.view.View.OnClickListener;

import

android.widget.EditText;

import

android.widget.LinearLayout;

import

android.widget.TextView;

import

android.widget.Toast;

import

cn.yzx.studentmanageros.domain.Student;

public

class

MainActivity

extends

Activity

implements

OnClickListener

{

private

static

final

String

TAG

=

"MainActivity";

private

EditText

et_name;

private

EditText

et_sex;

private

EditText

et_age;

private

LinearLayout

llStudentGroup;

//學生列表控件

private

List<Student>

studentList;

private

File

cacheFile

=

new

File(Environment.getExternalStorageDirectory(),

"student.xml");

@Override

protected

void

onCreate(Bundle

savedInstanceState)

{

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

init();

}

private

void

init()

{

studentList

=

new

ArrayList<Student>();

et_name

=

(EditText)

findViewById(R.id.et_name);

et_sex

=

(EditText)

findViewById(R.id.et_sex);

et_age

=

(EditText)

findViewById(R.id.et_age);

llStudentGroup

=

(LinearLayout)

findViewById(R.id.ll_student_group);

findViewById(R.id.btn_add).setOnClickListener(this);

findViewById(R.id.btn_save).setOnClickListener(this);

findViewById(R.id.btn_restore).setOnClickListener(this);

}

@Override

public

void

onClick(View

v)

{

switch

(v.getId())

{

case

R.id.btn_add:

//添加學生

//取出數(shù)據(jù)

String

name

=

et_name.getText().toString();

String

sex

=

et_sex.getText().toString();

String

age

=

et_age.getText().toString();

//控制臺打印數(shù)據(jù)

Log.e(TAG,

"name="+name+",sex="+sex+",age="+age);

//判斷是否有數(shù)據(jù)為空

if(TextUtils.isEmpty(name)

||

TextUtils.isEmpty(sex)

||

TextUtils.isEmpty(age)){

Toast.makeText(this,

"請重新輸入",

0).show();

break;

}

//封裝成Student實體

Student

student

=

new

Student(name,

sex,

Integer.valueOf(age));

//添加到學生列表中

addToStudentList(student);

break;

case

R.id.btn_save:

//保存數(shù)據(jù)

boolean

isSuccess

=

saveStudentList();

if(isSuccess){

Toast.makeText(this,

"保存成功",

0).show();

}else

{

Toast.makeText(this,

"保存失敗",

0).show();

}

break;

case

R.id.btn_restore:

//恢復數(shù)據(jù)

//

恢復數(shù)據(jù)之前,

需要把集合中和LinearLayout中的數(shù)據(jù)全部清空

studentList.clear();

//

把線性布局中所有的控件全部移除

llStudentGroup.removeAllViews();

//從文件中讀取數(shù)據(jù)

List<Student>

readStudentList

=

readStudentList();

//

把取出回來的數(shù)據(jù),

一條一條的添加到學生列表中

for

(Student

stu

:

readStudentList)

{

addToStudentList(stu);

}

break;

default:

break;

}

}

private

List<Student>

readStudentList()

{

List<Student>

studentList

=

null;

//

構(gòu)建一個XmlPullParser解析器對象

XmlPullParser

parser

=

Xml.newPullParser();

//

指定要解析的文件

try

{

parser.setInput(new

FileInputStream(cacheFile),

"utf-8");

//

開始解析:

獲取EventType解析事件,

循環(huán)去判斷事件

int

eventType

=

parser.getEventType();

Student

student

=

null;

while(eventType!=XmlPullParser.END_DOCUMENT){

//

當前的事件類型不等于結(jié)束的document,

繼續(xù)循環(huán)

String

tagName

=

parser.getName();

switch

(eventType)

{

case

XmlPullParser.START_TAG:

if("students".equals(tagName)){//<students>

studentList

=

new

ArrayList<Student>();

}else

if

("student".equals(tagName))

{//<student>

student

=

new

Student();

}else

if

("name".equals(tagName))

{

student.setName(parser.nextText());

}else

if

("sex".equals(tagName))

{

student.setSex(parser.nextText());

}else

if("age".equals(tagName)){

student.setAge(Integer.valueOf(parser.nextText()));

}

break;

case

XmlPullParser.END_TAG:

if("student".equals(tagName)){

studentList.add(student);

}

break;

default:

break;

}

eventType

=

parser.next();

//

取下一個事件類型

}

return

studentList;

}

catch

(Exception

e)

{

//

TODO

Auto-generated

catch

block

e.printStackTrace();

}

return

null;

}

private

boolean

saveStudentList()

{

String

path

=

cacheFile.getPath();

Log.e(TAG,

"保存文件的路徑:"+path);

//得到一個序列化對象

XmlSerializer

serializer

=

Xml.newSerializer();

try

{

//指定輸出流

serializer.setOutput(new

FileOutputStream(cacheFile),

"utf-8");

//寫start_document

serializer.startDocument("utf-8",

true);

//

寫<students>

serializer.startTag(null,

"students");

for

(Student

student

:

studentList)

{

Log.e(TAG,

student.toString());

//

寫<student>

serializer.startTag(null,

"student");

//

寫<name>

serializer.startTag(null,

"name");

serializer.text(student.getName());

//

寫