Android 中的 XMLPullParse getAttributeValue() returns android studio 中的空值

Question

我正在使用天气 API 开发天气应用程序，我必须使用 XMLPullParser.When 进行解析我输入国家名称我应该收到一些值，例如湿度、压力、温度。在我的代码中当我尝试解析第一个国家/地区名称字段 returns correctly.But 时，我无法接收其他字段。因为我正在使用 getAttributeValue(null,"value") 来解析这个值并且它 returns null value..

XML 文件位于 XML FILE HERE。

我的代码是： MainAcitivity.java

public class MainActivity extends Activity {
    EditText ed1,ed2,ed3,ed4,ed5;
    TextView tv2;

    private String url1 = "http://api.openweathermap.org/data/2.5/weather?q=";
    private String url2 = "&mode=xml";
    private HandleXML obj;
    Button b1;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        b1=(Button)findViewById(R.id.button);
        tv2=(TextView)findViewById(R.id.textView2);
        ed1=(EditText)findViewById(R.id.editText);
        ed2=(EditText)findViewById(R.id.editText2);
        ed3=(EditText)findViewById(R.id.editText3);
        ed4=(EditText)findViewById(R.id.editText4);
        ed5=(EditText)findViewById(R.id.editText5);

        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String url = ed1.getText().toString();
                tv2.setText(url);
                String finalUrl = url1 + url + url2;
                ed2.setText(finalUrl);

                obj = new HandleXML(finalUrl);
                obj.fetchXML();
                Log.i("MyActivity", "XML Parser View " + obj);

                while(obj.parsingComplete);
                Log.i("MyActivity", "XML Parsing Complete " + obj.parsingComplete);
                ed2.setText(obj.getCountry());
                ed3.setText(obj.getTemperature());
                ed4.setText(obj.getHumidity());
                ed5.setText(obj.getPressure());

            }
        });
    }

    @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);
    }

HandleXML.java

public class HandleXML {
    private String country = "country";
    private String temperature = "temperature";
    private String humidity = "humidity";
    private String pressure = "pressure";
    private String urlString = null;
    private XmlPullParserFactory xmlFactoryObject;
    public volatile boolean parsingComplete = true;

    public HandleXML(String url){
        this.urlString = url;
    }
    public String getCountry(){
        return country;
    }
    public String getTemperature(){
        return temperature;
    }
    public String getHumidity(){
        return humidity;
    }
    public String getPressure(){
        return pressure;
    }
    public void parseXMLAndStoreIt(XmlPullParser myParser) {
        int event;
        String text=null;
        try {
            event = myParser.getEventType();
            while (event != XmlPullParser.END_DOCUMENT) {
                String name=myParser.getName();
                switch (event){
                    case XmlPullParser.START_TAG:
                        break;
                    case XmlPullParser.TEXT:
                        text = myParser.getText();

                        if(name.equals("country")){
                            country = text;
                        }
                        else if(name.equals("humidity")){
                            humidity = myParser.getAttributeValue(null,"value");
                        }
                        else if(name.equals("pressure")){
                            pressure = myParser.getAttributeValue(null,"value");
                        }
                        else if(name.equals("temperature")){
                            temperature = myParser.getAttributeValue(null,"value");
                        }
                        else{
                        }
                        break;
                    case XmlPullParser.END_TAG:
                }
                event = myParser.next();
            }
            parsingComplete = false;
        }

        catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void fetchXML(){
        Thread thread = new Thread(new Runnable(){
            @Override
            public void run() {
                try {
                    URL url = new URL(urlString);
                    HttpURLConnection conn = (HttpURLConnection)url.openConnection();

                    conn.setReadTimeout(10000 /* milliseconds */);
                    conn.setConnectTimeout(15000 /* milliseconds */);
                    conn.setRequestMethod("GET");
                    conn.setDoInput(true);
                    conn.connect();

                    InputStream stream = conn.getInputStream();

                    xmlFactoryObject = XmlPullParserFactory.newInstance();
                    XmlPullParser myparser = xmlFactoryObject.newPullParser();

                    myparser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false);
                    myparser.setInput(stream, null);
                    parseXMLAndStoreIt(myparser);
                    stream.close();
                }
                catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
        thread.start();
    }

AndroidMAnifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.geevarughese.xmlpars">
    <uses-permission android:name="android.permission.INTERNET"/>

    <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>

Answer 1

改变案例 XmlPullParser.TEXT：

到

case XmlPullParser.START_TAG:

必须是

public void parseXMLAndStoreIt(XmlPullParser myParser) {
    int event;
    String text=null;
    try {
        event = myParser.getEventType();
        while (event != XmlPullParser.END_DOCUMENT) {
            String name=myParser.getName();
            switch (event){
                case XmlPullParser.START_TAG:
                    text = myParser.getText();

                    if(name.equals("country")){
                        country = text;
                    }
                    else if(name.equals("humidity")){
                        humidity = myParser.getAttributeValue(null,"value");
                    }
                    else if(name.equals("pressure")){
                        pressure = myParser.getAttributeValue(null,"value");
                    }
                    else if(name.equals("temperature")){
                        temperature = myParser.getAttributeValue(null,"value");
                    }
                    else{
                    }
                    break;
                case XmlPullParser.END_TAG:
            }
            event = myParser.next();
        }
        parsingComplete = false;
    }

    catch (Exception e) {
        e.printStackTrace();
    }
}

Android 中的 XMLPullParse getAttributeValue() returns android studio 中的空值

XMLPullParse in Android getAttributeValue() returns null value in android studio

android

xmlpullparser

xml-parsing