本文实例为大家分享了Android实现学生管理系统的关键性代码,供大家参考,具体内容如下
局部效果图:
实现代码:
1、布局
<?xml version=\"1.0\" encoding=\"utf-8\"?>
<manifest xmlns:android=\"http://schemas.android.com/apk/res/android\"
package=\"com.itheima27.sutdentmanager\"
android:versionCode=\"1\"
android:versionName=\"1.0\" >
<uses-sdk
android:minSdkVersion=\"8\"
android:targetSdkVersion=\"17\" />
<uses-permission android:name=\"android.permission.WRITE_EXTERNAL_STORAGE\"/>
<application
android:allowBackup=\"true\"
android:icon=\"@drawable/ic_launcher\"
android:label=\"@string/app_name\"
android:theme=\"@style/AppTheme\" >
<activity
android:name=\"com.itheima27.sutdentmanager.MainActivity\"
android:label=\"@string/app_name\"
android:theme=\"@android:style/Theme.NoTitleBar\" >
<intent-filter>
<action android:name=\"android.intent.action.MAIN\" />
<category android:name=\"android.intent.category.LAUNCHER\" />
</intent-filter>
</activity>
</application>
</manifest>
<LinearLayout xmlns:android=\"http://schemas.android.com/apk/res/android\"
android:layout_width=\"match_parent\"
android:layout_height=\"match_parent\"
android:background=\"@android:color/white\"
android:orientation=\"vertical\" >
<TextView
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_gravity=\"center_horizontal\"
android:layout_marginTop=\"5dip\"
android:text=\"学生管理系统\"
android:textColor=\"#99CCFF\"
android:textSize=\"23sp\" />
<RelativeLayout
android:layout_width=\"fill_parent\"
android:layout_height=\"wrap_content\"
android:layout_marginTop=\"5dip\"
android:padding=\"5dip\" >
<TextView
android:id=\"@+id/tv_name\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:paddingLeft=\"15dip\"
android:paddingRight=\"15dip\"
android:text=\"姓名\"
android:textSize=\"18sp\" />
<TextView
android:id=\"@+id/tv_sex\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_marginLeft=\"5dip\"
android:layout_toRightOf=\"@id/tv_name\"
android:paddingLeft=\"15dip\"
android:paddingRight=\"15dip\"
android:text=\"性别\"
android:textSize=\"18sp\" />
<TextView
android:id=\"@+id/tv_age\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_marginLeft=\"5dip\"
android:layout_toRightOf=\"@id/tv_sex\"
android:paddingLeft=\"15dip\"
android:paddingRight=\"15dip\"
android:text=\"年龄\"
android:textSize=\"18sp\" />
<EditText
android:id=\"@+id/et_name\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_alignLeft=\"@id/tv_name\"
android:layout_alignRight=\"@id/tv_name\"
android:layout_below=\"@id/tv_name\"
android:singleLine=\"true\" />
<EditText
android:id=\"@+id/et_sex\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_alignLeft=\"@id/tv_sex\"
android:layout_alignRight=\"@id/tv_sex\"
android:layout_below=\"@id/tv_sex\"
android:singleLine=\"true\" />
<EditText
android:id=\"@+id/et_age\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_alignLeft=\"@id/tv_age\"
android:layout_alignRight=\"@id/tv_age\"
android:layout_below=\"@id/tv_age\"
android:inputType=\"number\"
android:singleLine=\"true\" />
<Button
android:id=\"@+id/btn_add_student\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_alignBaseline=\"@id/et_age\"
android:layout_toRightOf=\"@id/et_age\"
android:text=\"添加学生\"
android:textSize=\"20sp\" />
</RelativeLayout>
<ScrollView
android:layout_width=\"fill_parent\"
android:layout_height=\"wrap_content\"
android:layout_weight=\"1\" >
<LinearLayout
android:id=\"@+id/ll_student_list\"
android:layout_width=\"fill_parent\"
android:layout_height=\"fill_parent\"
android:layout_margin=\"1dip\"
android:orientation=\"vertical\"
android:padding=\"5dip\" >
</LinearLayout>
</ScrollView>
<LinearLayout
android:layout_width=\"fill_parent\"
android:layout_height=\"wrap_content\"
android:layout_marginTop=\"5dip\"
android:orientation=\"horizontal\" >
<Button
android:id=\"@+id/btn_save\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_weight=\"1\"
android:text=\"保存数据\"
android:textSize=\"20sp\" />
<Button
android:id=\"@+id/btn_restore\"
android:layout_width=\"wrap_content\"
android:layout_height=\"wrap_content\"
android:layout_weight=\"1\"
android:text=\"恢复数据\"
android:textSize=\"20sp\" />
</LinearLayout>
</LinearLayout>
2、关键代码:
package com.itheima27.sutdentmanager.entities;
public class Student {
private String name;
private String sex;
private Integer age;
public Student(String name, String sex, Integer age) {
super();
this.name = name;
this.sex = sex;
this.age = age;
}
public Student() {
super();
// TODO Auto-generated constructor stub
}
public String getName() {
return name;
}
public void setName(String name) {
this.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;
}
@Override
public String toString() {
return \"Student [name=\" + name + \", sex=\" + sex + \", age=\" + age + \"]\";
}
}
package com.itheima27.sutdentmanager;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlSerializer;
import com.itheima27.sutdentmanager.entities.Student;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.graphics.Color;
import android.text.TextUtils;
import android.util.Xml;
import android.view.Menu;
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;
public class MainActivity extends Activity implements OnClickListener {
private EditText etName;
private EditText etSex;
private EditText etAge;
private LinearLayout llStudentList;
private List<Student> studentList;
private String filePath;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
}
private void init() {
etName = (EditText) findViewById(R.id.et_name);
etSex = (EditText) findViewById(R.id.et_sex);
etAge = (EditText) findViewById(R.id.et_age);
llStudentList = (LinearLayout) findViewById(R.id.ll_student_list);
findViewById(R.id.btn_save).setOnClickListener(this);
findViewById(R.id.btn_restore).setOnClickListener(this);
findViewById(R.id.btn_add_student).setOnClickListener(this);
studentList = new ArrayList<Student>();
filePath = Environment.getExternalStorageDirectory().getPath() + \"/student.xml\";
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_save:
if(studentList.size() > 0) {
if(saveStudent2Local()) {
Toast.makeText(this, \"保存成功\", 0).show();
} else {
Toast.makeText(this, \"保存失败\", 0).show();
}
} else {
Toast.makeText(this, \"当前没有数据\", 0).show();
}
break;
case R.id.btn_restore:
if(restoreStudentFromLocal()) {
Toast.makeText(this, \"恢复成功\", 0).show();
} else {
Toast.makeText(this, \"恢复失败\", 0).show();
}
break;
case R.id.btn_add_student:
addStudent();
break;
default:
break;
}
}
private boolean restoreStudentFromLocal() {
try {
XmlPullParser parser = Xml.newPullParser();
parser.setInput(new FileInputStream(filePath), \"utf-8\");
int eventType = parser.getEventType();
studentList.clear();
Student student = null;
String nodeName = null;
while(eventType != XmlPullParser.END_DOCUMENT) {
nodeName = parser.getName();
switch (eventType) {
case XmlPullParser.START_TAG:
if(\"student\".equals(nodeName)) {
student = new Student();
} else if(\"name\".equals(nodeName)) {
student.setName(parser.nextText());
} else if(\"sex\".equals(nodeName)) {
student.setSex(parser.nextText());
} else if(\"age\".equals(nodeName)) {
student.setAge(Integer.valueOf(parser.nextText()));
}
break;
case XmlPullParser.END_TAG:
if(\"student\".equals(nodeName)) {
studentList.add(student);
}
break;
default:
break;
}
eventType = parser.next();
}
refreshStudentList();
return true;
} catch (Exception e) {
e.printStackTrace();
}
return false;
}
private void refreshStudentList() {
llStudentList.removeAllViews();
TextView childView;
for (Student student : studentList) {
childView = new TextView(this);
childView.setTextSize(23);
childView.setTextColor(Color.BLACK);
childView.setText(\" \" + student.getName() + \" \" + student.getSex() + \" \" + student.getAge());
llStudentList.addView(childView);
}
}
private boolean saveStudent2Local() {
try {
XmlSerializer serializer = Xml.newSerializer();
serializer.setOutput(new FileOutputStream(filePath), \"utf-8\");
serializer.startDocument(\"utf-8\", true);
serializer.startTag(null, \"infos\");
for (Student stu : studentList) {
serializer.startTag(null, \"student\");
serializer.startTag(null, \"name\");
serializer.text(stu.getName());
serializer.endTag(null, \"name\");
serializer.startTag(null, \"sex\");
serializer.text(stu.getSex());
serializer.endTag(null, \"sex\");
serializer.startTag(null, \"age\");
serializer.text(String.valueOf(stu.getAge()));
serializer.endTag(null, \"age\");
serializer.endTag(null, \"student\");
}
serializer.endTag(null, \"infos\");
serializer.endDocument();
return true;
} catch (Exception e) {
e.printStackTrace();
}
return false;
}
private void addStudent() {
String name = etName.getText().toString();
String sex = etSex.getText().toString();
String age = etAge.getText().toString();
if(!TextUtils.isEmpty(name)
&& !TextUtils.isEmpty(sex)
&& !TextUtils.isEmpty(age)) {
studentList.add(new Student(name, sex, Integer.valueOf(age)));
TextView childView = new TextView(this);
childView.setTextSize(23);
childView.setTextColor(Color.BLACK);
childView.setText(\" \" + name + \" \" + sex + \" \" + age);
llStudentList.addView(childView);
} else {
Toast.makeText(this, \"请正确输入\", 0).show();
}
}
}
以上就是本文的全部内容,希望对大家的学习有所帮助。
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