文章选自StackOverflow(简称:SOF)精选问答汇总系列文章之一,本系列文章将为读者分享国外最优质的精彩问与答,供读者学习和了解国外最新技术。本文探讨Android显示当前日期和时间的方法。
问题:
如何在Android应用中显示当前日期和时间?
答案:
这个有多种解决方法。我假设你想把当前日期和时间放在TextView上。
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String currentDateTimeString = DateFormat.getDateTimeInstance().format( new Date()); // textView is the TextView view that should display it
textView.setText(currentDateTimeString); |
文档里可以阅读更多,点击 here 。你可以在那里读到更多信息,来更改用于转换的格式。
user647826
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public class XYZ extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); //setContentView(R.layout.main); Calendar c = Calendar.getInstance(); System.out.println( "Current time => " +c.getTime()); SimpleDateFormat df = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" ); String formattedDate = df.format(c.getTime()); // formattedDate have current date/time Toast.makeText( this , formattedDate, Toast.LENGTH_SHORT).show(); // Now we display formattedDate value in TextView TextView txtView = new TextView( this ); txtView.setText( "Current Date and Time : " +formattedDate); txtView.setGravity(Gravity.CENTER); txtView.setTextSize(20); setContentView(txtView); } } |
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public void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); setContentView(R.layout.main); Thread myThread = null ; Runnable runnable = new CountDownRunner(); myThread= new Thread(runnable); myThread.start(); } public void doWork() { runOnUiThread( new Runnable() { public void run() { try { TextView txtCurrentTime= (TextView)findViewById(R.id.lbltime); Date dt = new Date(); int hours = dt.getHours(); int minutes = dt.getMinutes(); int seconds = dt.getSeconds(); String curTime = hours + ":" + minutes + ":"
+ seconds; txtCurrentTime.setText(curTime); } catch (Exception e) {} } }); } class CountDownRunner implements Runnable{ // @Override public void run() { while (!Thread.currentThread().isInterrupted()){ try { doWork(); Thread.sleep(1000); } catch (InterruptedException e) { Thread.currentThread().interrupt(); } catch (Exception e){ } } } } |
要展示当前时间, AnalogClockView和DigitalClockView是明智的选择。
例如下面的布局:
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<?xml version= "1.0"
encoding= "utf-8" ?> <LinearLayout android:layout_width= "fill_parent" android:layout_height= "fill_parent" android:orientation= "vertical" > <AnalogClock android:layout_width= "fill_parent" android:layout_height= "wrap_content" /> <DigitalClock android:layout_width= "fill_parent" android:layout_height= "wrap_content" android:gravity= "center" android:textSize= "20sp" /> </LinearLayout> |
看起来是这个样子:
我自己的展示方法:
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Calendar c = Calendar.getInstance(); String sDate = c.get(Calendar.YEAR) + "-" + c.get(Calendar.MONTH) + "-" + c.get(Calendar.DAY_OF_MONTH) + " at " + c.get(Calendar.HOUR_OF_DAY) + ":" + c.get(Calendar.MINUTE); |
如果你想用特定的模式展示日期和时间,可以用这个:
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Date d = new Date(); CharSequence s = DateFormat.format( "yyyy-MM-dd hh:mm:ss" , d.getTime()); |
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Calendar c = Calendar.getInstance(); int month=c.get(Calendar.MONTH)+1; String sDate = c.get(Calendar.YEAR) + "-" + month+ "-"
+ c.get(Calendar.DAY_OF_MONTH) + "T" + c.get(Calendar.HOUR_OF_DAY)+ ":" +c.get(Calendar.MINUTE)+ ":" +c.get(Calendar.SECOND); |
这个展示日期的格式是 2010-05-24T18:13:00
这能显示当前时间和日期:
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public String getCurrDate() { String dt; Date cal = Calendar.getInstance().getTime(); dt = cal.toLocaleString(); return
dt; } |
如下代码:
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SimpleDateFormat dateFormat = new SimpleDateFormat( "yyyy/MM/dd HH:mm:ss" ); Calendar cal = Calendar.getInstance(); System.out.println( "time => " + dateFormat.format(cal.getTime())); String time_str = dateFormat.format(cal.getTime()); String[] s = time_str.split( " " ); for (int i = 0; i < s.length; i++) { System.out.println( "date => " + s[i]); } int year_sys = Integer.parseInt(s[0].split( "/" )[0]); int month_sys = Integer.parseInt(s[0].split( "/" )[1]); int day_sys = Integer.parseInt(s[0].split( "/" )[2]); int hour_sys = Integer.parseInt(s[1].split( ":" )[0]); int min_sys = Integer.parseInt(s[1].split( ":" )[1]); System.out.println( "year_sys => " + year_sys); System.out.println( "month_sys => " + month_sys); System.out.println( "day_sys => " + day_sys); System.out.println( "hour_sys => " + hour_sys); System.out.println( "min_sys => " + min_sys); |
原文链接:Display the current time and date in an Android application