Android StrictMode 总是提示 FileReader

Question

当启用 StrictMode 时，它​​总是提示 FileReader 有 DiskReadViolation。无论我如何改进，它仍然存在。我怀疑它与 UIThread 滞后问题有关，请告诉我如何解决它，谢谢。

06-03 15:28:19.764: D/dalvikvm(5726): GC_CONCURRENT freed 1515K, 60% free 3122K/7751K, external 4429K/4959K, paused 19ms+14ms
06-03 15:28:19.803: D/StrictMode(5726): StrictMode policy violation; ~duration=216 ms: android.os.StrictMode$StrictModeDiskReadViolation: policy=23 violation=2
06-03 15:28:19.803: D/StrictMode(5726):     at android.os.StrictMode$AndroidBlockGuardPolicy.onReadFromDisk(StrictMode.java:745)
06-03 15:28:19.803: D/StrictMode(5726):     at dalvik.system.BlockGuard$WrappedFileSystem.open(BlockGuard.java:228)
06-03 15:28:19.803: D/StrictMode(5726):     at java.io.FileInputStream.<init>(FileInputStream.java:80)
06-03 15:28:19.803: D/StrictMode(5726):     at java.io.FileInputStream.<init>(FileInputStream.java:132)
06-03 15:28:19.803: D/StrictMode(5726):     at java.io.FileReader.<init>(FileReader.java:66)
06-03 15:28:19.803: D/StrictMode(5726):     at util.CpuUtil.getCpuFreq(CpuUtil.java:30)

public static float getCpuFreq() {
    float result = -1;
    FileReader fr = null;
    BufferedReader br = null;
    try {
        fr = new FileReader("/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq");// (CpuUtil.java:30)
        br = new BufferedReader(fr);
        result = Float.parseFloat(br.readLine().trim());
        result = result / 1000;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            if (fr != null) {
                fr.close();
            }

            if (br != null) {
                br.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    return result;
}

编辑:getCpuFreq() 放在asynctask 里，但是onpostexcute() 放错地方了。 @rciovati，谢谢你的提醒，请在答案中发表你的话，这样我就可以接受了。

Answer 1

考虑使用 AsyncTask:

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        new YourAsyncTask().execute();
    }

    static class YourAsyncTask  extends AsyncTask<Void, Void, String> {

        @Override
        protected String doInBackground(Void... unused) {
            //Put your code inside here
        }
    }
}