Question

您好，我正在尝试将logcat的内容保存到手机存储中我的应用程序中的文件中，然后从应用程序中以字符串形式读取它的内容。

最终，我只想保存包含MediaMetadata的行（并使用正则表达式来执行此操作），但是现在我在读取文件内容时遇到了麻烦。

我相信我已成功将logcat保存到文件中，但是一旦我为文件路径调用openFileInput，我的程序就会不断崩溃。

在MainActivity中，每当我按下一个按钮时，我都会调用此函数：

public void onCreate(Context context) throws Exception {

//write file

super.onCreate();
String filename = "temp";
String filepath = "temp";

if ( isExternalStorageWritable() ) {

    File appDirectory = new File( Environment.getExternalStorageDirectory() + "/MyPersonalAppFolder" );
    //appDirectory = /storage/emulated/0/MyPersonalAppFolder

    File logDirectory = new File( appDirectory + "/log" );
    //logDirectory = /storage/emulated/0/MyPersonalAppFolder/log

    filename = "logcat" + System.currentTimeMillis() + ".txt";
    filepath = logDirectory+"/"+filename;
    //filepath = /storage/emulated/0/MyPersonalAppFolder/log/logcat1552017420176.txt
    Log.i("myTag", "filename = "+filename);
    Log.i("myTag", "filepath = "+filepath);

    File logFile = new File( filepath );
    // create app folder
    if ( !appDirectory.exists() ) {
        appDirectory.mkdir();
    }
    // create log folder
    if ( !logDirectory.exists() ) {
        logDirectory.mkdir();
    }
    // clear the previous logcat and then write the new one to the file
try {
    //Process process = Runtime.getRuntime().exec( "logcat -c");
    Process process = Runtime.getRuntime().exec( "logcat -d -f " + logFile );
    //Process process = Runtime.getRuntime().exec( "logcat -e \b(updateMediaMetaData) -f " + logFile );

    } catch ( IOException e ) {
        e.printStackTrace();
    }

    } else if ( isExternalStorageReadable() ) {
        // only readable
    } else {
        // not accessible
    }

    //read file
    Log.i("myTag", "now going to read file at filepath = "+filepath);

    String ret = "tempretoncreate";

    FileInputStream fis;
    Log.i("myTag", " here0");
    fis = openFileInput(filepath);
    Log.i("myTag", " here1");
    StringBuffer fileContent = new StringBuffer("");
    Log.i("myTag", " here2");
    //fis.close();

    Log.i("myTag", " ret = "+ret);

    Log.i("myTag", " end of onCreate() func");
}

**我的logcat调试语句类似于

2019-03-07 20：23：49.848 4634-4634 / com.example.savefile I / myTag：单击了按钮 2019-03-07 20：23：49.859 4634-4634 / com.example.savefile I / myTag：文件名= logcat1552019029859.txt 2019-03-07 20：23：49.860 4634-4634 / com.example.savefile I / myTag：文件路径= /storage/emulated/0/MyPersonalAppFolder/log/logcat1552019029859.txt 2019-03-07 20：23：49.867 4634-4634 / com.example.savefile I / myTag：现在将在文件路径= /storage/emulated/0/MyPersonalAppFolder/log/logcat1552019029859.txt中读取文件 2019-03-07 20：23：49.867 4634-4634 / com.example.savefile I / myTag：here0 2019-03-07 20：23：49.873 4634-4634 / com.example.savefile I / myTag：错误调用onCreate 2019-03-07 20：23：49.873 4634-4634 / com.example.savefile I / myTag：btnClick（）函数的结尾

所以最后被调用的是我的'here0'打印语句，这使我认为我没有在文件路径上正确调用openFileInput（“ /storage/emulated/0/MyPersonalAppFolder/loglogcat1552017420176.txt")

在我的android应用中将文件作为字符串读取文件是否正确？

android将logcat保存到手机上的文件并读取其内容

0 个答案: