1.我正在使用SD卡内的文本日志文件保存
Android GPS启用和禁用时间.
我想打印多行文本,而不删除上一行数据.
下面的代码是完美打印多行,但当应用程序保持睡眠和重新启动时.当GPS开启或关闭时,与先前数据一起打印一行.
帮我解决一下.
required Output:(after Restart the app) << GPs Enabled At :2016/06/08 17.15.00>> << GPs Disabled At :2016/06/08 17.45.00>> << GPs Enabled At :2016/06/08 17.49.00>> << GPs Disabled At :2016/06/08 17.52.00>> Getting Output:(after Restart the app) << GPs Enabled At :2016/06/08 17.15.00>> << GPs Disabled At :2016/06/08 17.45.00>> << GPs Enabled At :2016/06/08 17.49.00>> << GPs Disabled At :2016/06/08 17.52.00>> << GPs Disabled At :2016/06/08 17.52.00>> << GPs Disabled At :2016/06/08 17.52.00>>
public void Logmethod(String NoramalStr,String Dateval)
{
/* Log FOlder Text files Starts here*/
try {
File newFolder = new File(Environment.getExternalStorageDirectory(),"GpsFolder");
if (!newFolder.exists()) {
newFolder.mkdir();
}
try {
File file = new File(newFolder,"GPSStatus" + ".txt");
file.createNewFile();
/*Writing the Log in specific files*/
BufferedWriter out;
try {
String separator1 = System.getProperty("line.separator");
FileOutputStream fOut = new FileOutputStream(new File(newFolder + "/GPSStatus.txt"),true);
OutputStreamWriter osw = new OutputStreamWriter(fOut);
osw.append("<< " + NoramalStr +" : "+Dateval + " >>");
osw.append(separator1); // this will add new line ;
osw.flush();
osw.close();
fOut.close();
Log.i(NoramalStr," : "+Dateval);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} catch (Exception ex) {
System.out.println("ex: " + ex);
}
} catch (Exception e) {
System.out.println("e: " + e);
}
}
解决方法
如果有关删除日志文件的问题：
你总是做createNewFile尝试检查文件是否存在
你总是做createNewFile尝试检查文件是否存在
public void Logmethod(String NoramalStr,String Dateval) {
try {
File newFolder = new File(Environment.getExternalStorageDirectory(),"GpsFolder");
boolean directoryExists = newFolder.exists();
Log.d(TAG," directoryExists = " + directoryExists);
if (!directoryExists) {
boolean dirCreate = newFolder.mkdir();
Log.d(TAG," dirCreate = " + dirCreate);
}
File file = new File(newFolder,"GPSStatus" + ".txt");
boolean fileExists = file.exists();
Log.d(TAG," fileExists = " + fileExists);
if (!fileExists) {
boolean fileCreateResult = file.createNewFile();
Log.d(TAG," fileCreateResult = " + fileCreateResult);
}
String separator1 = System.getProperty("line.separator");
FileOutputStream fOut = new FileOutputStream(new File(newFolder + "/GPSStatus.txt"),true);
OutputStreamWriter osw = new OutputStreamWriter(fOut);
osw.append("<< ");
osw.append(NoramalStr);
osw.append(" : ");
osw.append(Dateval);
osw.append(" >>");
osw.append(separator1); // this will add new line ;
osw.flush();
osw.close();
fOut.close();
Log.i(TAG," : " + Dateval);
} catch (Exception e) {
e.printStackTrace();
}
}
如果是关于位置提供者的永久监听启用/禁用
看看How do I receive the system broadcast when GPS status has changed?
并在清单文件中使用接收器
<receiver android:name=".GPStStatusReceiver">
<intent-filter>
<action android:name="android.location.PROVIDERS_CHANGED" />
</intent-filter>
</receiver>
