如何解析嵌套的 RSS 提要？答案

【问题标题】：How to parse nested RSS feeds?如何解析嵌套的 RSS 提要？
【发布时间】：2018-01-31 20:08:28
【问题描述】：

我能够从 URL 获取所有必需的数据。但我想获取<item>...</item> 属性作为列表。我能够一一获取所有属性。我想要完整的项目属性列表。他们还有其他选择吗？

这是 rss 解析的代码。

public class HandleXML {

    public volatile boolean parsingComplete = true;
    private String title = "title";
    private String link = "link";
    private String description = "description";
    private String image = "image";
    private String imageTitle = "title";
    private String imageDescription = "description";
    private String imageLink = "link";
    private String guid = "guid";
    private String pubDate = "pubDate";
    private String media_content = "media:content";
    private String urlString = null;
    private XmlPullParserFactory xmlFactoryObject;
    private boolean isImage = false;

    public boolean isParsingComplete() {
        return parsingComplete;
    }

    public void setParsingComplete(boolean parsingComplete) {
        this.parsingComplete = parsingComplete;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public void setLink(String link) {
        this.link = link;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this.image = image;
    }

    public String getImageTitle() {
        return imageTitle;
    }

    public void setImageTitle(String imageTitle) {
        this.imageTitle = imageTitle;
    }

    public String getImageDescription() {
        return imageDescription;
    }

    public void setImageDescription(String imageDescription) {
        this.imageDescription = imageDescription;
    }

    public String getImageLink() {
        return imageLink;
    }

    public void setImageLink(String imageLink) {
        this.imageLink = imageLink;
    }

    public String getGuid() {
        return guid;
    }

    public void setGuid(String guid) {
        this.guid = guid;
    }

    public String getPubDate() {
        return pubDate;
    }

    public void setPubDate(String pubDate) {
        this.pubDate = pubDate;
    }

    public String getMedia_content() {
        return media_content;
    }

    public void setMedia_content(String media_content) {
        this.media_content = media_content;
    }

    public String getUrlString() {
        return urlString;
    }

    public void setUrlString(String urlString) {
        this.urlString = urlString;
    }

    public HandleXML(String url) {
        this.urlString = url;
    }

    public String getTitle() {
        return title;
    }

    public String getLink() {
        return link;
    }

    public String getDescription() {
        return description;
    }

    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();
                        break;

                    case XmlPullParser.END_TAG:

                        if (!isImage && name.equals("title")) {
                            title = text;
                            Log.e("Input text : ",text);
                        }
                        else if (!isImage && name.equals("link")) {
                            link = text;
                            Log.e("Input link : ",text);
                        }
                        else if (!isImage && name.equals("description")) {
                            description = text;
                            Log.e("Input description : ",text);
                        }
                        else if (name.equals("image")) {
                            image = text;
                            isImage = true;
                            Log.e("Input image : ",text);
                        }
                        else if (isImage && name.equals("title")) {
                            imageTitle = text;
                            Log.e("Input image title : ",text);
                        }
                        else if (isImage && name.equals("description")) {
                            imageDescription = text;
                            Log.e("Input image descr : ",text);
                        }
                        else if (isImage && name.equals("link")) {
                            imageLink = text;
                            Log.e("Input link : ",text);
                        }
                        else if (isImage && name.equals("guid")) {
                            guid = text;
                            Log.e("Input guid : ",text);
                        }
                        else if (isImage && name.equals("pubDate")) {
                            pubDate = text;
                            Log.e("Input pubdate : ",text);
                        }
                        else if (isImage && name.equals("media:content")) {
                            media_content = text;
//                            isImage = false;
                            Log.e("Input media:content : ",text);
                        }
                        break;
                }
                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);
                    // Starts the query
                    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) {
                }
            }
        });
        thread.start();
    }
}

如何获取项目列表？请帮忙。

【问题讨论】：

标签： android xml-parsing rss

【解决方案1】：

你应该 1) 将 Item 类作为模型从 HandleXML 中分离出来。 2）在频道标签的开头，初始化一个项目列表。 3）在项目标签的开头，创建一个新的项目对象。 4) 相应地填充 Item 对象。 5）在item标签的最后，将Item对象添加到list中。

您应该注意isImage 变量。 init 应该是 true，一旦你创建了一个 item 对象，设置为 false。 sn-p 如下：

public class HandleXML {

    public volatile boolean parsingComplete = true;
    private String image = "image";
    private String imageTitle = "title";
    private String imageDescription = "description";
    private String imageLink = "link";
    private String urlString = null;
    private XmlPullParserFactory xmlFactoryObject;
    private boolean isImage = true; // isImage init to be true

    private List<Item> itemList = null;

    // separate the Item class with HandleXML
    class Item {
        private String title = "title";
        private String link = "link";
        private String description = "description";
        private String guid = "guid";
        private String pubDate = "pubDate";
        private String media_content = "media:content";

        public void setTitle(String title) {
            this.title = title;
        }

        public void setLink(String link) {
            this.link = link;
        }

        public void setDescription(String description) {
            this.description = description;
        }

        public String getGuid() {
            return guid;
        }

        public void setGuid(String guid) {
            this.guid = guid;
        }

        public String getPubDate() {
            return pubDate;
        }

        public void setPubDate(String pubDate) {
            this.pubDate = pubDate;
        }

        public String getMedia_content() {
            return media_content;
        }

        public void setMedia_content(String media_content) {
            this.media_content = media_content;
        }

        public String getTitle() {
            return title;
        }

        public String getLink() {
            return link;
        }

        public String getDescription() {
            return description;
        }
    }

    public boolean isParsingComplete() {
        return parsingComplete;
    }

    public void setParsingComplete(boolean parsingComplete) {
        this.parsingComplete = parsingComplete;
    }


    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this.image = image;
    }

    public String getImageTitle() {
        return imageTitle;
    }

    public void setImageTitle(String imageTitle) {
        this.imageTitle = imageTitle;
    }

    public String getImageDescription() {
        return imageDescription;
    }

    public void setImageDescription(String imageDescription) {
        this.imageDescription = imageDescription;
    }

    public String getImageLink() {
        return imageLink;
    }

    public void setImageLink(String imageLink) {
        this.imageLink = imageLink;
    }

    public String getUrlString() {
        return urlString;
    }

    public void setUrlString(String urlString) {
        this.urlString = urlString;
    }

    public HandleXML(String url) {
        this.urlString = url;
    }


    public void parseXMLAndStoreIt(XmlPullParser myParser) {
        int event;
        String text = null;
        Item newItem = null;

        try {
            event = myParser.getEventType();

            while (event != XmlPullParser.END_DOCUMENT) {
                String name = myParser.getName();

                switch (event) {
                    case XmlPullParser.START_TAG:
                        if (name.equalsIgnoreCase("channel")) {
                            // init the list for item.
                            itemList = new ArrayList<Item>();
                        }
                        if (name.equalsIgnoreCase("item")) {
                            // create a new item object.
                            newItem = new Item();
                            isImage = false; // isImage to false
                        }
                        break;

                    case XmlPullParser.TEXT:
                        text = myParser.getText();
                        break;

                    case XmlPullParser.END_TAG:

                        if (!isImage && name.equals("title")) {
                            newItem.setTitle(text);
                            Log.e("Input text : ",text);
                        }
                        else if (!isImage && name.equals("link")) {
                            newItem.setLink(text);
                            Log.e("Input link : ",text);
                        }
                        else if (!isImage && name.equals("description")) {
                            newItem.setDescription(text);
                            Log.e("Input description : ",text);
                        }
                        else if (name.equals("image")) {
                            image = text;
                            isImage = true;
                            Log.e("Input image : ",text);
                        }
                        else if (isImage && name.equals("title")) {
                            imageTitle = text;
                            Log.e("Input image title : ",text);
                        }
                        else if (isImage && name.equals("description")) {
                            imageDescription = text;
                            Log.e("Input image descr : ",text);
                        }
                        else if (isImage && name.equals("link")) {
                            imageLink = text;
                            Log.e("Input link : ",text);
                        }
                        else if (!isImage && name.equals("guid")) {
                            newItem.setGuid(text);
                            Log.e("Input guid : ",text);
                        }
                        else if (!isImage && name.equals("pubDate")) {
                            newItem.setPubDate(text);
                            Log.e("Input pubdate : ",text);
                        }
                        else if (!isImage && name.equals("media:content")) {
                            newItem.setMedia_content(text);
//                            isImage = false;
                            Log.e("Input media:content : ",text);
                        }
                        else if (name.equalsIgnoreCase("item")) {
                            // add the item to list in the end of item tag
                            itemList.add(newItem);
                            Log.e("itemList", "Add one");
                        }
                        break;
                }
                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);
                    // Starts the query
                    conn.connect();
                    InputStream stream = conn.getInputStream();

                    xmlFactoryObject = XmlPullParserFactory.newInstance();
                    XmlPullParser myparser = xmlFactoryObject.newPullParser();
                    myparser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false);
                    myparser.setInput(stream, "UTF_8");
                    parseXMLAndStoreIt(myparser);
                    stream.close();
                } catch (Exception e) {
                }
            }
        });
        thread.start();
    }
}

【讨论】：

它显示 ItemList 大小始终为 0。项目永远不会添加到 List 中。
请再次检查sn-p。我测试的项目将被添加到列表中。