我想知道什么是类似于javascript的setInterval的类似于我正在尝试以定期的间隔将数据发布到服务器，例如10秒以下是代码。
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tv=(TextView)findViewById(R.id.textview);
text = "";
try {
postData(); // display the data
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void postData() throws JSONException{
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
final Random myRandom = new Random();
HttpPost httppost = new HttpPost("http://mywebpage.com/index.php?id="+myRandom.nextInt(100000));
JSONObject json = new JSONObject();
try {
JSONArray postjson=new JSONArray();
postjson.put(json);
// Post the data:
StringEntity se = new StringEntity( "JSON: " + json.toString());
se.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
httppost.setEntity(se);
// Execute HTTP Post Request
System.out.print(json);
HttpResponse response = httpclient.execute(httppost);
// for JSON:
if(response != null)
{
InputStream is = response.getEntity().getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
text = sb.toString();
}
tv.setText(text);
}catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
int initialDelay = 1000;
int period = 5000;
Timer timer = new Timer();
TimerTask task = new TimerTask() {
public void run() {
Looper.prepare();
try {
postData();
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Looper.loop();
Looper.myLooper().quit();
}
};
timer.scheduleAtFixedRate(task, initialDelay, period);
}
欢迎所有回复：）
日志文件：
01-21 02:07:30.441: W/dalvikvm(575): threadid=7: thread exiting with uncaught exception (group=0x4001d800)
01-21 02:07:30.451: E/AndroidRuntime(575): FATAL EXCEPTION: Timer-0
01-21 02:07:30.451: E/AndroidRuntime(575): android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
01-21 02:07:30.451: E/AndroidRuntime(575): at android.view.ViewRoot.checkThread(ViewRoot.java:2802)
01-21 02:07:30.451: E/AndroidRuntime(575): at android.view.ViewRoot.invalidateChild(ViewRoot.java:607)
01-21 02:07:30.451: E/AndroidRuntime(575): at android.view.ViewRoot.invalidateChildInParent(ViewRoot.java:633)
01-21 02:07:30.451: E/AndroidRuntime(575): at android.view.ViewGroup.invalidateChild(ViewGroup.java:2505)
01-21 02:07:30.451: E/AndroidRuntime(575): at android.view.View.invalidate(View.java:5139)
01-21 02:07:30.451: E/AndroidRuntime(575): at android.widget.TextView.checkForRelayout(TextView.java:5364)
答案 0 :(得分：2)
我认为这正是您所寻找的：Android scheduleAtFixedRate
答案 1 :(得分：0)
我想，你可以使用我的Clock类。 它启动/停止计时并在已注册的TextView字段中显示时间和/或日期。
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import android.os.Handler;
import android.widget.TextView;
/**
* The class for creating and refreshing many different fields on different layouts,
* that can hold actual time and/or date in different formats
* The formats should be as in http://developer.android.com/reference/java/text/SimpleDateFormat.html.
* Only present and visible fields are being actualized, so there is no need to clean the clock list after closing an activity
*
* Examples of use:
*
* Clock.registerClock((TextView) findViewById(R.id.TimeField), "HH:mm");
* Clock.registerClock((TextView) findViewById(R.id.DateField), "d.M.yyyy EEE");
* Clock.start(10000L);
*
* @author Petr Gangnus
*/
public final class Clock {
/**
* the handler that works instead of timer and supports UI
*/
static private Handler handler = new Handler();
/**
* the interval of the time refreshing
*/
static private long refreshStep;
/**
* pairs TextView timer+time/date format
*/
private TextView clockFace;
private String format;
private Clock(TextView clockFace, String format){
this.clockFace=clockFace;
this.format=format;
}
// here is the list of views containing the visual timers that should be held actual
static private ArrayList<Clock> clocks=new ArrayList<Clock>();
/**
* fills all timer fields by actual time value, according to their formats.
*/
static private Runnable mUpdateTimeTask = new Runnable() {
public void run() {
for(Clock clock:clocks){
showActualTimeDate(clock);
}
handler.postDelayed(this,refreshStep);
}
};
//============================================ public members ====================================================================
/**
* add a clock to the list of updating clocks
* @param clockFace - the place where the time or date will be shown
* @param format - the format of the time/date
* @return
*/
public static boolean registerClock(TextView clockFace, String format){
if (clockFace==null) return false;
if(clocks.contains(clockFace)){
// old clockFace
clocks.get(clocks.indexOf(clockFace)).format=format;
} else {
// new clockFace
clocks.add(new Clock(clockFace, format));
}
return true;
}
/**
* remove a clock from the updating list
* @param clockFace
* @return
*/
public static boolean unRegisterClock(TextView clockFace){
if (clockFace==null) return false;
if(clocks.contains(clockFace)){
// found clockFace
clocks.remove(clocks.indexOf(clockFace));
} else {
// not found clockFace
return false;
}
return true;
}
/**
* put in the "place" the actual date/time in the appropriate "format"
* @param place
* @param format
*/
public static void showActualTimeDate(Clock clock){
if (clock.clockFace==null) return;
if (clock.clockFace.getVisibility()!=TextView.VISIBLE) return;
Date thisDate=new Date();
SimpleDateFormat df=new SimpleDateFormat(clock.format);
clock.clockFace.setText(df.format(thisDate));
}
/**
* start the ticking for all clocks
* @param step the tick interval
*/
public static void start(long step) {
refreshStep=step;
handler.removeCallbacks(mUpdateTimeTask);
handler.postDelayed(mUpdateTimeTask, 0);
}
/**
* Stopping ticking all clocks (not removing them)
* the calling could be put somewhere in onStop
*/
public static void stop() {
handler.removeCallbacks(mUpdateTimeTask);
}
}