Warning: file_get_contents(/data/phpspider/zhask/data//catemap/9/java/319.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
Java ArrayList的RGenerator<;字符串>;?_Java_Android - Fatal编程技术网

Java ArrayList的RGenerator<;字符串>;?

Java ArrayList的RGenerator<;字符串>;?,java,android,Java,Android,这是我到目前为止的代码: // Read Text File entitled wordsEn.txt public String readFromFile() { String words = ""; // Array List That Words being added to ArrayList<String> wordLineArray = new ArrayList<String

这是我到目前为止的代码:

// Read Text File entitled wordsEn.txt 
        public String readFromFile() {
            String words = "";
            // Array List That Words being added to
            ArrayList<String> wordLineArray = new ArrayList<String>();

            try { 
                InputStream inputstream = openFileInput("wordsEn.txt");
                if (inputstream != null) {
                    InputStreamReader inputStreamReader = new InputStreamReader(inputstream);
                    BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
                    String receiveString = "";
                    StringBuilder stringBuilder = new StringBuilder();

                    while ( (receiveString = bufferedReader.readLine()) != null ) {
                        wordLineArray.add(receiveString);
                        stringBuilder.append(receiveString);
                    }
                    inputstream.close();
                    words = stringBuilder.toString();
                }

            }
            catch (FileNotFoundException e) {
                Log.e("login activity", "File not found: " + e.toString());
            } catch (IOException e) {
                Log.e("login activity", "Can not read file: " + e.toString());
            }

            return words;
          //R Generator for Strings in wordLineArray 

            //String RandomWord = wordLineArray[rgenerator.
        }       

}
//读取名为wordsEn.txt的文本文件
公共字符串readFromFile(){
字串=”;
//要添加到的单词的数组列表
ArrayList wordLineArray=新的ArrayList();
试试{
InputStream InputStream=openFileInput(“wordsEn.txt”);
如果(inputstream!=null){
InputStreamReader InputStreamReader=新的InputStreamReader(inputstream);
BufferedReader BufferedReader=新的BufferedReader(inputStreamReader);
字符串receiveString=“”;
StringBuilder StringBuilder=新的StringBuilder();
而((receiveString=bufferedReader.readLine())!=null){
wordLineArray.add(receiveString);
stringBuilder.append(receiveString);
}
inputstream.close();
words=stringBuilder.toString();
}
}
catch(filenotfounde异常){
Log.e(“登录活动”,“未找到文件:”+e.toString());
}捕获(IOE异常){
Log.e(“登录活动”,“无法读取文件:+e.toString());
}
返回单词;
//wordLineArray中字符串的R生成器
//字符串RandomWord=wordLineArray[rgenerator。
}       
}

我希望从worldLineArray中选择一个随机字符串,并将其存储到名为RandomWord的字符串中。然后,我希望该随机词显示在文本视图中。我的文本视图id为:testview1

您可以使用
random
类生成随机数,然后从arrayList中选择元素,如下所示:

Random random= new Random();
String random = wordLineArray.get(random.nextInt(wordLineArray.size()));

您可以使用
java.util.Random
生成一个介于0和
wordLineArray.size()之间的随机数-1
然后使用此数字作为索引,从您的
wordLineArray
中选择要显示在文本视图中的单词。

我不喜欢集合。shuffle。您可以刷新我的内存,找到一种可能的方法来使用它吗?您可以用它来洗牌集合,然后需要选择元素。否则,请使用Random类来选择Random elementI在使用nextInt时出错。还有“list”指的是什么。好的。nextInt表示它未定义。是因为它是字符串吗?nextInt是一个随机方法,它将返回介于0和wordLineArray大小之间的数字