android学生管理系统，利用linerLayout，实现xml的读取和写入，以及按钮的事件处理
在这里我只展示，几个类的主要代码
还是一句老话，注意写入权限的使用
操作类
package com.leige.stu.op;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.WriteAbortedException;
import java.util.ArrayList;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlSerializer;
import android.os.Environment;
import android.util.Log;
import android.util.Xml;
import com.leige.stu.domain.Student;
public class StudentDaoimpl implements StudentDao{
//保存到sd卡中
@Override
public void save(List list){
//获取解析器
//解析范本
/*
*
*
* 战三
* 男
* 18
*
*
* */
XmlSerializer write=Xml.newSerializer();
File path=new File(Environment.getExternalStorageDirectory(),"students.xml");
try {
//实例化输出流
FileOutputStream out=new FileOutputStream(path);
//解析器绑定输出流，设置编码
write.setOutput(out, "utf-8");
//开始写xml
write.startDocument("utf-8",true);
//开始根节点
write.startTag(null, "students");
//循环写入student
for(Student stu:list){
//子节点student
write.startTag(null, "student");
//设置id
write.attribute(null, "id", String.valueOf(stu.getId()));
write.startTag(null, "name");//name
write.text(stu.getName());
write.endTag(null, "name");
//age
write.startTag(null, "age");
write.text(String.valueOf(stu.getAge()));
write.endTag(null, "age");
//sex
write.startTag(null, "sex");
write.text(stu.getSex());
write.endTag(null, "sex");
write.endTag(null, "student");
}
write.endTag(null, "students");
//结束
write.endDocument();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
Log.i("err",e.toString());
}
}
//读取
//解析范本
/*
*
*
* 战三
* 男
* 18
*
*
* */
@Override
public List getStuList(){
//获取读取解析器
XmlPullParser read=Xml.newPullParser();
File path=new File(Environment.getExternalStorageDirectory(),"students.xml");
List students=null;
Student student=null;
try {
FileInputStream input=new FileInputStream(path);
read.setInput(input,"utf-8");
//获取时间类型
int eventType=read.getEventType();
//设置循环读取
while(eventType!=XmlPullParser.END_DOCUMENT){
//获取当前节点，名字
String eleName=read.getName();
switch (eventType) {
case XmlPullParser.START_TAG:
{
if(eleName.equals("students")){//students
//建立集合
students=new ArrayList();
}else if(eleName.equals("student")){
//实例化对象
student=new Student();
//设置id属性
student.setId(Integer.parseInt(read.getAttributeValue(null, "id")));
}else if(eleName.equals("name")){//name
//设置name
student.setName(read.nextText());
}else if(eleName.equals("age")){//age
student.setAge(Integer.parseInt(read.nextText()));
}else if(eleName.equals("sex")){//sex
student.setSex(read.nextText());
}
}
break;
case XmlPullParser.END_TAG:
{
if(eleName.equals("student")){
//加入集合
students.add(student);
}else if(eleName.equals("students")){
return students;
}
}
break;
}
eventType=read.next();
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
} 主活动类
package com.leige.stu;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.Inflater;
import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import com.leige.stu.domain.Student;
import com.leige.stu.op.StudentDao;
import com.leige.stu.op.StudentDaoimpl;
public class MainActivity extends Activity implements OnClickListener{
private LinearLayout show=null;
private Button add=null;
private EditText name=null;
private EditText age=null;
private Spinner sex=null;
private String sexValue;
String[] arr;
int count=0;
//声明操作类
StudentDao dao=new StudentDaoimpl();
//声明保存集合
List students=new ArrayList();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//实例化布局对象
show=(LinearLayout) findViewById(R.id.show);
add=(Button) findViewById(R.id.add);
name=(EditText) findViewById(R.id.name);
age=(EditText) findViewById(R.id.age);
sex= (Spinner) findViewById(R.id.sex);
arr=new String[]{"男","女"};
//设置下拉菜单内容
ArrayAdapter adapter=new ArrayAdapter(this,
android.R.layout.simple_spinner_item,arr);
//设置下拉列表的风格
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
//设置适配器
sex.setAdapter(adapter);
sex.setVisibility(View.VISIBLE);
sex.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView parent, View view,
int position, long id) {
// TODO Auto-generated method stub
sexValue=arr[position];
}
@Override
public void onNothingSelected(AdapterView parent) {
// TODO Auto-generated method stub
}
});
for(Student stu:dao.getStuList()){
addView(stu);
students.add(stu);
}
}
//声明对象
Student student;
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.add:
{
String stuName=name.getText().toString();
if(stuName==""||stuName.trim().length()<=0){
Toast.makeText(this, "姓名不能为空", Toast.LENGTH_SHORT).show();
break;
}
int stuAge = 0;
try {
stuAge=Integer.parseInt(age.getText().toString());
} catch (Exception e) {
Toast.makeText(this, "年龄输入不正确", Toast.LENGTH_SHORT).show();
break;
}
//实例化对象
student=new Student();
//设置对象
student.setAge(stuAge);
student.setId(count++);
student.setSex(sexValue);
student.setName(stuName);
//将students实例化，并把student加入集合
students.add(student);
addView(student);
//清空编辑文本
name.setText("");
age.setText("");
}
break;
case R.id.save:
{
if(students!=null){
dao.save(students);
Toast.makeText(this, "保存成功", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(this, "保存失败", Toast.LENGTH_SHORT).show();
}
}
break;
case R.id.cancel:
{
Toast.makeText(this, "取消保存", Toast.LENGTH_SHORT).show();
}
break;
}
}
private void addView(Student stu) {
// TODO Auto-generated method stub
//加载显示文件布局，建议放在外面，因为不必要每次都加在布局文件
View view=LayoutInflater.from(this).inflate(R.layout.item, null);
TextView show_name=(TextView) view.findViewById(R.id.show_name);
TextView show_age=(TextView) view.findViewById(R.id.show_age);
TextView show_sex=(TextView) view.findViewById(R.id.show_sex);
//设置显示文本
show_name.setText(stu.getName());
show_age.setText(String.valueOf(stu.getAge()));
show_sex.setText(stu.getSex());
show.addView(view);
}
}
布局效果图
