編輯:關於android開發
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.yanlei.wifi" > <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <!-- 在SDCard中創建與刪除文件權限 --> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/> <!-- 連接<a href="http://www.it165.net/news/nhlw/" target="_blank" class="keylink">互聯網</a>Internet權限 --> <uses-permission android:name="android.permission.INTERNET" /> <!-- GPS定位權限 --> <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" /> <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" /> <uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name=".MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <Button android:id="@+id/btn1" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="創建XML文件" /> <Button android:id="@+id/btn2" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="DOM解析XML" /> <TextView android:id="@+id/result" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>
package com.example.yanlei.wifi; import android.content.Context; import android.net.wifi.ScanResult; import android.net.wifi.WifiManager; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.NodeList; import org.xml.sax.SAXException; import org.xmlpull.v1.XmlPullParser; import org.xmlpull.v1.XmlPullParserException; import org.xmlpull.v1.XmlPullParserFactory; import org.xmlpull.v1.XmlSerializer; import android.app.Activity; import android.os.Bundle; import android.util.Log; import android.util.Xml; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; import android.widget.Toast; import java.util.List; public class MainActivity extends AppCompatActivity { private static final String BOOKS_PATH = "/sdcard/books.xml"; private View mButton1,mButton2,mButton3; private TextView mTextView; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); setupViews(); } //初始化工作 private void setupViews(){ mTextView = (TextView)findViewById(R.id.result); mButton1 = (View)findViewById(R.id.btn1); mButton2 = (View)findViewById(R.id.btn2); mButton1.setOnClickListener(new Button1ClickListener()); mButton2.setOnClickListener(new Button2ClickListener()); } private class Button1ClickListener implements View.OnClickListener { public void onClick(View v) { createXmlFile(); } } private class Button2ClickListener implements View.OnClickListener { public void onClick(View v) { domParseXML(); } } //創建xml文件 private void createXmlFile(){ File linceseFile = new File(BOOKS_PATH); try{ linceseFile.createNewFile(); }catch (IOException e) { Log.e("IOException", "exception in createNewFile() method"); } FileOutputStream fileos = null; try{ fileos = new FileOutputStream(linceseFile); }catch (FileNotFoundException e) { Log.e("FileNotFoundException", "can't create FileOutputStream"); } XmlSerializer serializer = Xml.newSerializer(); try { serializer.setOutput(fileos,"UTF-8"); serializer.startDocument(null, true); serializer.startTag(null, "books"); for(int i = 0; i < 3; i ++){ serializer.startTag(null, "book"); serializer.startTag(null, "bookname"); serializer.text("Android教程" + i); serializer.endTag(null, "bookname"); serializer.startTag(null, "bookauthor"); serializer.text("Frankie" + i); serializer.endTag(null, "bookauthor"); serializer.endTag(null, "book"); } serializer.endTag(null, "books"); serializer.endDocument(); serializer.flush(); fileos.close(); } catch (Exception e) { Log.e("Exception","error occurred while creating xml file"); } Toast.makeText(getApplicationContext(), "創建xml文件成功!", Toast.LENGTH_SHORT).show(); } //dom解析xml文件 private void domParseXML(){ File file = new File(BOOKS_PATH); DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); DocumentBuilder db = null; try { db = dbf.newDocumentBuilder(); } catch (ParserConfigurationException e) { e.printStackTrace(); } Document doc = null; try { doc = db.parse(file); } catch (SAXException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } Element root = doc.getDocumentElement(); NodeList books = root.getElementsByTagName("book"); String res = "本結果是通過dom解析:" + "/n"; for(int i = 0; i < books.getLength();i++){ Element book = (Element)books.item(i); Element bookname = (Element)book.getElementsByTagName("bookname").item(0); Element bookauthor = (Element)book.getElementsByTagName("bookauthor").item(0); res += "書名: " + bookname.getFirstChild().getNodeValue() + " " + "作者: " + bookauthor.getFirstChild().getNodeValue() + "/n"; } mTextView.setText(res); } @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); } }
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