如何在Android Studio中将CSV文件解析为数组

时间:2016-07-16 21:12:54

标签: java android arrays csv parsing

我想知道如何解析CSV文件并将内容存储到数组中。我的csv文件看起来像这样:

class TracingInterface(Frame):
    def __init__(self, master):
        super().__init__()

        # 1) master instead of root (it was just a typo I think)
        master.minsize(width=700, height=520)
        master.maxsize(width=700, height=520)
        # Frame.__init__(self, master): redundant with super().__init__()
        Grid.config(self)
        self.TracingMethod()
        self.logDetails()
        self.otherFunctionInterface()
        # Default window state
        self._configureUA_window = None

    def UAconfig_window(self):
        if self._configureUA_window is not None:
            return None
        # 2) changed self which is a frame to the actual window self.master
        self._configureUA_window = cA.ConfigureUAinterface(self.master)

我只想要名字,所以第二个字段。我想将csv中的所有这些项存储到数组或字符串的arraylist中。

任何想法如何做到这一点?

非常感谢任何帮助!

5 个答案:

答案 0 :(得分:17)

将CSV文件放在Android中的位置 在“res”文件夹中创建一个名为“raw”的文件夹,并将CSV文件放入其中。

如何阅读CSV文件, 自Android以来没什么特别之处。我们将使用我们的标准Java代码。最好使用我们自己的代码而不是使用API​​。下面的类是一个读取CSV文件的实用程序,它可以在Android应用程序中使用。 我们将在哪个数组中存储csv文件的项目 在这些例子中,它是得分表arraylist。

<div class="radio">
    <label><input type="radio" name="optradio"/>Option 1</label>
 </div>
 <div class="radio">
     <label><input type="radio" name="optradio"/>Option 2</label>
 </div>

那么如何从“raw”文件夹加载CSV文件并使用上面的实用程序来读取它?

public class CSVFile {
    InputStream inputStream;

    public CSVFile(InputStream inputStream){
        this.inputStream = inputStream;
    }

    public List read(){
        List resultList = new ArrayList();
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
        try {
            String csvLine;
            while ((csvLine = reader.readLine()) != null) {
                String[] row = csvLine.split(",");
                resultList.add(row);
            }
        }
        catch (IOException ex) {
            throw new RuntimeException("Error in reading CSV file: "+ex);
        }
        finally {
            try {
                inputStream.close();
            }
            catch (IOException e) {
                throw new RuntimeException("Error while closing input stream: "+e);
            }
        }
        return resultList;
    }
}

<强> MainActivity.java

InputStream inputStream = getResources().openRawResource(R.raw.stats);
CSVFile csvFile = new CSVFile(inputStream);
List scoreList = csvFile.read();

<强> ItemArrayAdapter.java

public class MainActivity extends Activity {
    private ListView listView;
    private ItemArrayAdapter itemArrayAdapter;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listView = (ListView) findViewById(R.id.listView);
        itemArrayAdapter = new ItemArrayAdapter(getApplicationContext(), R.layout.item_layout);

        Parcelable state = listView.onSaveInstanceState();
        listView.setAdapter(itemArrayAdapter);
        listView.onRestoreInstanceState(state);

        InputStream inputStream = getResources().openRawResource(R.raw.stats);
        CSVFile csvFile = new CSVFile(inputStream);
        List scoreList = csvFile.read();

        for(String[] scoreData:scoreList ) {
            itemArrayAdapter.add(scoreData);
        }
    }
}

<强> activity_mail.xml

public class ItemArrayAdapter extends ArrayAdapter {
    private List scoreList = new ArrayList();

    static class ItemViewHolder {
        TextView name;
        TextView score;
    }

    public ItemArrayAdapter(Context context, int textViewResourceId) {
        super(context, textViewResourceId);
    }

    @Override
    public void add(String[] object) {
        scoreList.add(object);
        super.add(object);
    }

    @Override
    public int getCount() {
        return this.scoreList.size();
    }

    @Override
    public String[] getItem(int index) {
        return this.scoreList.get(index);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View row = convertView;
        ItemViewHolder viewHolder;
        if (row == null) {
            LayoutInflater inflater = (LayoutInflater) this.getContext().
                    getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = inflater.inflate(R.layout.item_layout, parent, false);
            viewHolder = new ItemViewHolder();
            viewHolder.name = (TextView) row.findViewById(R.id.name);
            viewHolder.score = (TextView) row.findViewById(R.id.score);
            row.setTag(viewHolder);
        } else {
            viewHolder = (ItemViewHolder)row.getTag();
        }
        String[] stat = getItem(position);
        viewHolder.name.setText(stat[0]);
        viewHolder.score.setText(stat[1]);
        return row;
    }
}

<强> item_layout.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.javapapers.android.csvfileread.app.MainActivity">
    <ListView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:id="@+id/listView"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="10dp" />
</RelativeLayout>

对于整个源代码,您可以引用这些链接javapapers.com/wp-content/uploads/2014/07/CSVFileRead.zip

我认为这会有所帮助

答案 1 :(得分:2)

免责声明:我从未使用Android,但我确实了解Java,所以希望它们都一样。

话虽如此,你可以尝试这样的事情。

Scanner scanner = new Scanner(new File("file.csv"));
ArrayList<String> pokemon = new ArrayList<>();
while(scanner.hasNextLine()) {
    pokemon.add(scanner.nextLine().split(",")[1]);
}
scanner.close();

答案 2 :(得分:0)

Android默认情况下不会创建原始文件夹。在项目中的res / raw下创建一个原始文件夹。复制你的CSV文件。将CSV文件的名称保留为小写,并在询问时转换为文本格式。我的CSV文件名是welldata.scv WellData - 它是带有getter和setter的模型类。 wellDataList是用于存储数据的ArrayList。

private void readData() {
InputStream is = getResources().openRawResource(R.raw.welldata);
BufferedReader reader = new BufferedReader(
        new InputStreamReader(is, Charset.forName("UTF-8")));
String line = "";
try {
    while ((line = reader.readLine()) != null) {
       //set splitter
        String[] tokens = line.split(",");

        //read the data
        WellData wellData = new WellData();
        wellData.setOwner(tokens[0]);
        wellData.setApi(tokens[1]);
        wellData.setLongitude(tokens[2]);
        wellData.setLatitude(tokens[3]);
        wellData.setProperty(tokens[4]);
        wellData.setWellName(tokens[5]);
        wellDataList.add(wellData);

        Log.d("MainActivity" ,"Just Created " +wellData);

    }
} catch (IOException e1) {
    Log.e("MainActivity", "Error" + line, e1);
    e1.printStackTrace();
}

} }

答案 3 :(得分:0)

更好的CSV解析器可以处理带引号的字段

    import android.content.Context;
    import android.widget.Toast;
    import java.io.BufferedReader;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.InputStream;
    import java.io.InputStreamReader;
    import java.util.ArrayList;
    import java.util.List;

    public class CSVReader {
        private class StringDArray {
            private String[] data=new String[0];
            private int used=0;
            public void add(String str) {
                if (used >= data.length){
                    int new_size= used+1;
                    String[] new_data=new String[new_size];
                    java.lang.System.arraycopy( data,0,new_data,0,used);
                    data=new_data;
                }
                data[used++] = str;
            }
            public int length(){
                return  used;
            }
            public String[] get_araay(){
                return data;
            }
        }
        private  Context context;
        public CSVReader(Context context){
            this.context=context;
        }
        public List read(File file){
            List resultList = new ArrayList();
            try{
                InputStream inputStream= new FileInputStream(file);
                BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
                String csvLine;
                final char Separator = ',';
                final char Delimiter = '"';
                final char LF = '\n';
                final char CR = '\r';
                boolean quote_open = false;
                while ((csvLine = reader.readLine()) != null) {
                    //String[] row = csvLine.split(",");// simple way
                    StringDArray a=new StringDArray();
                    String token="";
                        csvLine+=Separator;
                    for(char c:csvLine.toCharArray()){
                        switch (c){
                            case LF: case CR:// not required as we are already read line
                                quote_open=false;
                                a.add(token);
                                token="";
                            break;
                            case Delimiter:
                                quote_open=!quote_open;
                            break;
                            case Separator:
                                if(quote_open==false){
                                    a.add(token);
                                    token="";
                                }else{
                                    token+=c;
                                }
                            break;
                            default:
                                token+=c;
                            break;
                        }
                    }
                    if(a.length()>0 ) {
                        if(resultList.size()>0){
                            String[] header_row =(String[]) resultList.get(0);
                            if(a.length()>=header_row.length) {
                                String[] row = a.get_araay();
                                resultList.add(row);
                            }
                        }else{
                            String[] row = a.get_araay();
                            resultList.add(row);//header row
                        }
                    }
                }
                inputStream.close();
            }catch (Exception e){
                Toast.makeText(context,"Error : " + e.getMessage(), Toast.LENGTH_LONG).show();
            }
            return resultList;
        }
    }

用法

    File file=new File(path);
    CSVReader csvReader=new CSVReader(activity.this);
    List csv=csvReader.read(file);
    if(csv.size()>0){
        String[] header_row =(String[]) csv.get(0);
        if(header_row.length>1){
            String col1=header_row[0];
            String col2=header_row[1];
        }
    }

    Toast.makeText(activity.this,csv.size() + " rows", Toast.LENGTH_LONG).show();

使用的示例数据
ID,名称
1,测试项目1
“ 2”,“测试项目2”
“ 3”,“测试,项目3”
4,测试项目4

答案 4 :(得分:0)

我扩展了Sharma的回答,以使核心类在各种CSV文件条件下都更加灵活。我更喜欢使用构建器设计模式来配置如何读取CSV文件。

public class CSVFile {
    private static final Charset UTF8 = Charset.forName("UTF-8");
    private final static String DEFAULT_DELIMITER = ",";

    private InputStream inputStream;
    private Charset charset;
    private String delimiter;
    private boolean ignoreHead;

    public CSVFile(InputStream inputStream) {
        this.inputStream = inputStream;
        this.charset = UTF8;
        this.delimiter = DEFAULT_DELIMITER;
        this.ignoreHead = false;
    }

    public CSVFile setCharset(Charset charset) {
        this.charset = charset;
        return this;
    }

    public CSVFile setDelimiter(String delimiter) {
        this.delimiter = delimiter;
        return this;
    }

    public CSVFile ignoreHead() {
        ignoreHead = true;
        return this;
    }

    public List<String[]> read() {
        boolean firstRow = true;
        List<String[]> resultList = new ArrayList<>();
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, charset));
        try {
            String csvLine;
            while ((csvLine = reader.readLine()) != null) {
                if (firstRow) {
                    firstRow = false;

                    if (ignoreHead) {
                        continue;
                    }
                }

                String[] row = csvLine.split(delimiter);
                resultList.add(row);
            }
        } catch (IOException ex) {
            throw new RuntimeException("Error in reading CSV file: " + ex);
        } finally {
            try {
                inputStream.close();
            } catch (IOException e) {
                throw new RuntimeException("Error while closing input stream: " + e);
            }
        }
        return resultList;
    }
}