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目前我正在从事需要解析远程文本文件并将其存储在本地存储（内部/外部）中的项目。我能够解析文本文件，但无法将其存储在 SDCARD 中。这是我的代码：

package com.exercise.AndroidInternetTxt;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.MalformedURLException;
import java.net.URL;

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

public class AndroidInternetTxt extends Activity {

    TextView textMsg, textPrompt;
    final String textSource = "http://sites.google.com/site/androidersite"
                                                              + "/text.txt";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        textPrompt = (TextView) findViewById(R.id.textprompt);
        textMsg = (TextView) findViewById(R.id.textmsg);
        textPrompt.setText("Wait...");
        URL textUrl;
        try {
            textUrl = new URL(textSource);
            BufferedReader bufferReader = new BufferedReader(
                    new InputStreamReader(textUrl.openStream()));
            String StringBuffer;
            String stringText = "";
            while ((StringBuffer = bufferReader.readLine()) != null) {
                stringText += StringBuffer;
            }
            bufferReader.close();
            textMsg.setText(stringText);
            // Saving the parsed data.........
            File myFile = new File("sdcard/mysdfile.txt");
            if (!myFile.exists()) {
                myFile.mkdirs();
            }
            myFile = new File("sdcard/mysdfile.txt");
            myFile.createNewFile();
            FileOutputStream fOut = new FileOutputStream(myFile);
            OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
            myOutWriter.append(textMsg.getText());
            myOutWriter.close();
            fOut.close();
            Toast.makeText(getBaseContext(), "Done writing SD 'mysdfile.txt'",
                Toast.LENGTH_SHORT).show();
        } catch (MalformedURLException e) {
            e.printStackTrace();
            textMsg.setText(e.toString());
        } catch (IOException e) {
            e.printStackTrace();
            textMsg.setText(e.toString());
        }
        textPrompt.setText("Finished!");
    }
}

这是我的清单文件-

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.exercise.AndroidInternetTxt"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="4" />
    <uses-permission android:name="android.permission.INTERNET"/>

    <application android:label="@string/app_name">
        <activity android:name=".AndroidInternetTxt"
                  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>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE"/>
</manifest>

但是，我的问题是-

  • 如何将解析后的文本数据存储在 SDCARD 或手机内存中的文件中？
  • 有什么方法可以使用计时器以预定义的时间间隔检查 URL？

任何代码示例对我来说都很棒。

4

3 回答 3

11

首先，您的AndroidManifest.xml文件是正确的。所以没必要纠正。尽管我建议将您的权限组织在一个地方。

将文件写入内部存储

FileOutputStream fOut = openFileOutput("myinternalfile.txt",MODE_WORLD_READABLE);
OutputStreamWriter osw = new OutputStreamWriter(fOut);

//---write the contents to the file---
osw.write(strFileData);
osw.flush();
osw.close();

将文件写入外部 SD 卡

//This will get the SD Card directory and create a folder named MyFiles in it.
File sdCard = Environment.getExternalStorageDirectory();
File directory = new File (sdCard.getAbsolutePath() + "/MyFiles");
directory.mkdirs();

//Now create the file in the above directory and write the contents into it
File file = new File(directory, "mysdfile.txt");
FileOutputStream fOut = new FileOutputStream(file);
OutputStreamWriter osw = new OutputStreamWriter(fOut);
osw.write(strFileData);
osw.flush();
osw.close();

注意：如果在模拟器上运行，请确保您已在 AVD 属性中启用 SD 卡支持并为其分配适当的空间。

于 2012-07-02T09:00:02.047 回答
1

替换此行

File myFile = new File("sdcard/mysdfile.txt");
if(!myFile.exists()){
  myFile.mkdirs();
 }
myFile = new File("sdcard/mysdfile.txt");

和

//保存解析后的数据.........

File myFile = new File(Environment.getExternalStorageDirectory()+"/mysdfile.txt");
myFile.createNewFile();
于 2012-07-02T08:27:10.217 回答
0 
File myFile = new File("sdcard/mysdfile.txt");

应改为

File myFile = new File("/mnt/sdcard/mysdfile.txt");
于 2012-07-02T08:52:47.540 回答