Question

我一直致力于创建应用。我注意到我需要使用模式匹配器从网站获取信息并将其显示在Android应用上。我对Android App Development仍然有点新意，但我认为我在Java方面还不错。我在Eclipse中尝试了这个完全相同的代码并且它起作用，所以我有点困惑为什么Android Studio会有所不同。

基本上，我有一个textview，我试图填充维基百科的国家。这些州是拥有海滩的州。我在Eclipse上写的正则表达式抓住了所有状态甚至一些额外的美国领域，并在控制台中显示它们，但在Android中并非如此。

public static String patternMatcher()
{
    try {
        URL getUrlContent = new URL("https://en.wikipedia.org/wiki/List_of_beaches_in_the_United_States");
        BufferedReader reader = new BufferedReader(new InputStreamReader(getUrlContent.openStream()));
        String line;

        Pattern stateForBeach = Pattern.compile("<h3>(.*>)(.*?)</span><span class=\"mw-editsection\"><span class=\"mw-editsection-bracket\">", Pattern.DOTALL);
        //Pattern beach = Pattern.compile("<li><a href=\"(.*?>)(.*?)</a></li>");
        Matcher matcher1;
        while ((line = reader.readLine()) != null) {
            matcher1 = stateForBeach.matcher(line);
            if (matcher1.find()) {
                matcherString = "States: " + matcher1.group(2);
            }
        }
    }
    catch (Exception ex)
    {
        System.out.println("Error: " + ex);
    }
    return matcherString;
}

这是将状态添加到textview

的方法

public void addItemsToTextView()
{
    patternMatcherTextView = (TextView) findViewById(R.id.patternMatcherTextView);
    System.out.println(patternMatcher());
    patternMatcherTextView.setText(patternMatcher());
}

这是onCreate app方法

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_which_beach);
    stateSpinner = (Spinner) findViewById(R.id.stateSpinner);
    patternMatcherTextView = (TextView) findViewById(R.id.patternMatcherTextView);
    patternMatcherTextView.setText(patternMatcher());
    addItemsToStateSpinner();
    stateSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

            selectedState = stateSpinner.getSelectedItem().toString();
            System.out.println("State "+selectedState+" has been selected");

        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });
    addItemsToTextView();
}

字符串和旋转器已经在上面声明和初始化。

如何在android studio中正确使用模式匹配器？

0 个答案: