Android附加文本文件

Question

我想把对话选择器的唤醒时间和休眠时间记录到像这样的文本文件中，但调用方法commitToFile2不会附加文本文件“savedData.txt。”

我知道这段代码非常脏。我是Java的新手，所以任何其他建议都会非常感激。

package com.buttinyourface;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.TimePickerDialog;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.TimePicker;
import android.widget.AdapterView.OnItemClickListener;

public class SettingsActivity extends Activity {

    public int wakeHour;
    public int wakeMinute;
    public int sleepHour;
    public int sleepMinute;
    public String sleepHourText = "No Data";
    public String sleepMinuteText = "No Data";
    public String outputTime = "No Data";
    public String wakeHourText = "No Data";
    private ListView lv;
    Dialog newDialogBox;
    Context appContext;
    protected Context context;
    static final private int WAKE_TIME = 0;
    static final private int SLEEP_TIME = 1;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.settings);
        final String[] settingsList = getResources().getStringArray(
                R.array.settingsStringArray);
        lv = (ListView) findViewById(R.id.list);
        TextView wakeHourTextView = (TextView) findViewById(R.id.TextView01);
        lv.setOnItemClickListener(new OnItemClickListener() {

            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                int settingsPosition = position;
                if (settingsPosition == 0) {
                    showDialog(WAKE_TIME);
                    wakeHourText = Integer.toString(wakeHour);
                }
                if (settingsPosition == 1) {
                    showDialog(SLEEP_TIME);
                }
            }
        });
        lv.setAdapter(new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, settingsList));
        wakeHourTextView.setText(outputTime);
    }

    public void onPrepareDialog(int id, Dialog dialog) {
        switch (id) {
        case WAKE_TIME:
            break;
        case SLEEP_TIME:
            break;
        }
    }

    @Override
    public Dialog onCreateDialog(int id) {
        switch (id) {
        case WAKE_TIME:
            return new TimePickerDialog(this, WakeTimeSetListener, wakeHour,
                    wakeMinute, false);
        case SLEEP_TIME:
            return new TimePickerDialog(this, SleepTimeSetListener, sleepHour,
                    sleepMinute, false);
        }
        return null;
    }

    private TimePickerDialog.OnTimeSetListener WakeTimeSetListener =
                          new TimePickerDialog.OnTimeSetListener() {
        public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
            wakeHour = hourOfDay;
            wakeMinute = minute;
            String wakeHourText = Integer.toString(hourOfDay);
            String wakeMinuteText = Integer.toString(minute);
            String preftime = hourOfDay + ":" + minute;
            SimpleDateFormat df = new SimpleDateFormat("HH:mm");
            SimpleDateFormat dfOut = new SimpleDateFormat("hh:mma");
            Date date = null;
            try {
                date = df.parse(preftime);
            } catch (ParseException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            String outputWakeTime = dfOut.format(date);
            try {
                commitToFile(wakeHourText, wakeMinuteText, outputWakeTime);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    };
    private TimePickerDialog.OnTimeSetListener SleepTimeSetListener =
                          new TimePickerDialog.OnTimeSetListener() {
        public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
            sleepHour = hourOfDay;
            sleepMinute = minute;
            String sleepHourText = Integer.toString(hourOfDay);
            String sleepMinuteText = Integer.toString(minute);
            String preftime = hourOfDay + ":" + minute;
            SimpleDateFormat df = new SimpleDateFormat("HH:mm");
            SimpleDateFormat dfOut = new SimpleDateFormat("hh:mma");
            Date date = null;
            try {
                date = df.parse(preftime);
            } catch (ParseException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            String sleepOutputTime = dfOut.format(date);
            try {
                commitToFile2(sleepHourText, sleepMinuteText, sleepOutputTime);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    };

    private void commitToFile(String wakeHourText, String wakeMinuteText,
            String outputWakeTime) throws IOException {
        final String entryString = new String("wakeHour=" + wakeHourText
                + ";wakeMinute=" + wakeMinuteText + ";wakeTime="
                + outputWakeTime + ";");
        FileOutputStream fOut = openFileOutput("savedData.txt",
                MODE_WORLD_READABLE);
        OutputStreamWriter osw = new OutputStreamWriter(fOut);
        osw.write(entryString);
        osw.flush();
        osw.close();
    }

    private void commitToFile2(String sleepHourText, String sleepMinuteText,
            String sleepOutputTime) throws IOException {
        final String entryString = new String("sleepHour=" + sleepHourText
                + ";sleepMinute=" + sleepMinuteText + ";sleepTime="
                + sleepOutputTime + ";");
        FileOutputStream fOut = openFileOutput("savedData.txt",
                MODE_WORLD_READABLE);
        OutputStreamWriter osw = new OutputStreamWriter(fOut);
        osw.write(entryString);
        osw.flush();
        osw.close();
    }
}

Answer 1

我想通了......我不得不改变这条线

FileOutputStream fOut = openFileOutput("savedData.txt", MODE_WORLD_READABLE);

到

FileOutputStream fOut = openFileOutput("savedData.txt",  MODE_APPEND);

之后，我能够附加文本文件，而不会覆盖文本文件中已有的数据。谢谢你的帮助。我想有时会去google IS的第4页。

Answer 2

这样您就可以保留MODE_WORLD_READABLE

openFileOutput("savedData.txt", MODE_APPEND | MODE_WORLD_READABLE ); 

Answer 3

在commitToFile2()方法中，fw.append(entryString);尝试添加fw.flush();

之后

FileWriter是OutputStreamWriter的子类，该类的write()方法不一定会自动“刷新”数据。