android - 如何在 Android 中执行 handler.postDelayed 时删除卡住 UI？

Question

我需要每 10 秒显示一次 toast ，所以我可以使用 handler.postDelayed 线程来解决这个问题。但是这个线程卡住 UI 1-2 秒，那么我怎样才能删除卡住的 UI？

这是我的代码:

Runnable runnable = new Runnable() {
    @Override
    public void run() {
        gps = new TrackGPS(this);
        if (gps.canGetLocation()) {
            longitude = gps.getLongitude();
            latitude = gps.getLatitude();
            Geocoder geocoder = new Geocoder(this, Locale.getDefault());
            List<Address> addresses = geocoder.getFromLocation(latitude, longitude, 1);
            String address = addresses.get(0).getAddressLine(0);
            mTextView.setText(address + "\n" + "Lat:" + latitude + "Lon:" + longit‌​ude);
        }
        handler.postDelayed(this, 10000);
    }
};

Handler handler = new Handler();
handler.postDelayed(runnable, 10000);

Answer 1

这是一个 Activity 类，它显示了您应该在何处声明和初始化某些字段，以及如何使用 AsyncTask 在后台线程中运行地理编码器。代码未按原样编译，因为原始代码 fragment 缺少某些类型和声明。

public class MainActivity extends Activity {

    private Handler mHandler;

    private Runnable mRunnable;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Initialize other stuff

        mHandler = new Handler(Looper.getMainLooper());

        mRunnable = new Runnable() {
            @Override
            public void run() {
                new LocationAsyncTask().execute();
            }
        };

        mHandler.postDelayed(mRunnable, 10000);
    }

    private class LocationAsyncTask extends AsyncTask<Void, Void, String[]> {
        @Override
        protected String[] doInBackground(Void... params) {
            gps = new TrackGPS(this);
            if (gps1.canGetLocation()) {
                longitude = gps.getLongitude();
                latitude = gps.getLatitude();
                Geocoder geocoder = new Geocoder(MainActivity.this, Locale.getDefault());
                List<Address> addresses = geocoder.getFromLocation(latitude, longitude, 1);
                String address = addresses.get(0).getAddressLine(0);
                String[] strings = new String[3];
                strings[0] = address;
                strings[1] = latitude;
                strings[2] = longitude;
                return strings;
            } else {
                return null;
            }
        }

        @Override
        protected void onPostExecute(String[] strings) {
            super.onPostExecute(strings);
            if (strings != null) {
                updateText(strings[0], strings[1], strings[2]);
            }
            mHandler.postDelayed(mRunnable, 10000);
        }
    }
}