一、在Android中使用到的计时/倒计时方式
1,统一布局文件 activity_main.xml文件
<span style="font-size:18px;"><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
//用于显示计时效果
<TextView
android:id="@+id/show"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world"
android:textSize="20sp" />
</RelativeLayout></span>
2,具体实现方式
(一)Timer、TimerTask 【倒计时模式】
<span style="font-size:18px;">public class MainActivity extends Activity {
private TextView tv;
private int timeDownStart = 88;
Timer timer = new Timer();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.show);
//延迟2秒 执行周期:每隔1秒执行一次
timer.schedule(task, 2000, 1000);
}
/**
* 第一种倒计时方式:Timer 和 TimerTask
*/
TimerTask task = new TimerTask() {
@Override
public void run() {
runOnUiThread(new Runnable() {
@Override
public void run() {
timeDownStart--;
tv.setText(timeDownStart + "");
if (timeDownStart < 0) {
timer.cancel();
tv.setText("tv finish----------");
}
}
});
}
};
}</span>
(二)Timer、TimerTask、Handler 【倒计时模式】
<span style="font-size:18px;">public class MainActivity extends Activity {
private TextView tv;
private int timeDownStart = 66;
Timer timer = new Timer();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.show);
timer.schedule(task, 0, 1000);//不延迟
}
/**
* 第二种倒计时方式
*/
TimerTask task = new TimerTask() {
@Override
public void run() {
timeDownStart--;
Message msg = new Message();
msg.what = 1;
handler.sendMessage(msg);
}
};
Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
tv.setText(timeDownStart + "");
if (timeDownStart < 0) {
timer.cancel();
tv.setText("tv finish!");
}
break;
}
super.handleMessage(msg);
}
};
}</span>
(三)Handler 和Message 【倒计时模式】
<span style="font-size:18px;">public class MainActivity extends Activity {
private TextView tv;
private int timeDownStart = 66;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.show);
Message msg = handler.obtainMessage(1);
handler.sendMessageDelayed(msg, 1000);
}
/**
* 第三种倒计时方式
*/
Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
timeDownStart--;
tv.setText(timeDownStart + "");
if (timeDownStart > 0) {
Message msg = handler.obtainMessage(1);
handler.sendMessageDelayed(msg, 1000);
} else {
tv.setText("tv finish~_~");
}
break;
}
super.handleMessage(msg);
}
};
}</span>
(四)Handler 和 Thread 【计时模式】
<span style="font-size:18px;">public class MainActivity extends Activity {
/**
* 第四种计时方式:Handler 和 Thread
*/
private TextView tv;
private int startNum = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.show);
new Thread(new MyThread()).start();//没有停止
}
/**
* 第四种计时方式
*/
class MyThread implements Runnable {
@Override
public void run() {
while (true) {
try {
Thread.sleep(1000);
Message msg = new Message();
msg.what = 1;
handler.sendMessage(msg);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
startNum++;
tv.setText(startNum + "");
break;
}
super.handleMessage(msg);
}
};
}</span>
(五)Handler 和 Runnable【计时模式】
<span style="font-size:18px;">public class MainActivity extends Activity {
/**
* 第五种计时方式:Handler 和 Runnable
*/
private TextView tv;
private int startNum = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.show);
handler.postDelayed(runnable, 1000);
}
/**
* 第五种计时方式
*/
Handler handler = new Handler();
Runnable runnable = new Runnable() {
@Override
public void run() {
startNum++;
tv.setText(startNum + "");
handler.postDelayed(runnable, 1000);
}
};
}</span>
(六)CountDownTimer【倒计时模式】
<span style="font-size:18px;">public class MainActivity extends Activity {
/**
* 第六种倒计时方式:CountDownTimer
*/
private MyCount mc;
private TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.show);
mc = new MyCount(30000, 1000);
mc.start();
}
/**
* 第六种倒计时方式:CountDownTimer
*/
class MyCount extends CountDownTimer {
public MyCount(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
@Override
public void onTick(long millisUntilFinished) {
tv.setText("请等待30秒(" + millisUntilFinished / 1000 + ")...");
Toast.makeText(MainActivity.this, "bababba", Toast.LENGTH_SHORT);
//toast有延迟显示
}
@Override
public void onFinish() {
tv.setText("tv finish。。。。。。");
}
}
}</span>
第五种方式最简洁,第六种方式最实用;Handler会实时刷新界面,同时也就最耗资源;开启子线程启动刷新比较合理,但是在销毁的时候一定先销毁子线程,释放资源。
二、时间选择器
1,时间选择xml布局文件 date_picker_layout
<span style="font-size:18px;"><?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<DatePicker
android:id="@+id/datePicker"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
<EditText
android:id="@+id/dateEt"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:cursorVisible="false"
android:editable="false" />
<TimePicker
android:id="@+id/timePicker"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
<EditText
android:id="@+id/timeEt"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:cursorVisible="false"
android:editable="false" />
</LinearLayout></span>
2,实现主类
<span style="font-size:18px;">public class DatePickerActivity extends Activity {
private EditText dateEt = null;
private EditText timeEt = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.date_picker_layout);
dateEt = (EditText) findViewById(R.id.dateEt);
timeEt = (EditText) findViewById(R.id.timeEt);
DatePicker datePicker = (DatePicker) findViewById(R.id.datePicker);
TimePicker timePicker = (TimePicker) findViewById(R.id.timePicker);
/****************************************************************************/
datePicker.updateDate(2014,10,10);
timePicker.setCurrentHour(16);
/****************************************************************************/
Calendar calendar = Calendar.getInstance();
// int year = calendar.get(Calendar.YEAR);
// int monthOfYear = calendar.get(Calendar.MONTH);
// int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);
//year, monthOfYear, dayOfMonth,
datePicker.init(2014,8,15, new DatePicker.OnDateChangedListener() {
public void onDateChanged(DatePicker view, int year,
int monthOfYear, int dayOfMonth) {
dateEt.setText("您选择的日期是:" + year + "年" + (monthOfYear + 1) + "月" + dayOfMonth + "日");
}
});
timePicker.setOnTimeChangedListener(new TimePicker.OnTimeChangedListener() {
public void onTimeChanged(TimePicker view, int hourOfDay, int minute) {
timeEt.setText("您选择的时间是:" + hourOfDay + "时" + minute + "分");
}
});
}</span>
<span style="font-size:18px;">}</span>
效果图:
三、倒计时实现
1,布局文件
(一)设置开始时间 time_out_layout
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<DigitalClock
android:id="@+id/myClock"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_margin="10dp"
android:textSize="30sp" />
<TextView
android:id="@+id/text_select"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/myClock"
android:layout_centerHorizontal="true"
android:text="设置时间"
android:textSize="20sp" />
<EditText
android:id="@+id/minute"
android:layout_width="60dp"
android:layout_height="80dp"
android:layout_alignLeft="@id/myClock"
android:layout_below="@id/text_select"
android:layout_marginTop="20dp"
android:gravity="center"
android:inputType="number" />
<EditText
android:id="@+id/second"
android:layout_width="60dp"
android:layout_height="80dp"
android:layout_below="@id/text_select"
android:layout_marginTop="20dp"
android:layout_toRightOf="@id/minute"
android:gravity="center"
android:inputType="number" />
<Button
android:id="@+id/button_start"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:gravity="center"
android:padding="10dp"
android:text="开始倒计时"
android:textSize="30sp" />
</RelativeLayout>
(二)展示倒计时效果 start.xml
<span style="font-size:18px;"><?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/myTime"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_margin="30dp"
android:gravity="center"
android:textColor="#FF0000"
android:textSize="100sp"
android:textStyle="bold" />
</LinearLayout></span>
2,实现主类
(一)TimeOutActivity
public class TimeOutActivity extends Activity {
Button startButton;
EditText minuteText;
EditText secondText;
int minute;
int second;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.time_out_layout);
startButton = (Button) findViewById(R.id.button_start);
minuteText = (EditText)findViewById(R.id.minute);
secondText = (EditText)findViewById(R.id.second);
startButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!minuteText.getText().toString().equals("")) {
minute = Integer.parseInt(minuteText.getText().toString());
}
if (!secondText.getText().toString().equals("")) {
second = Integer.parseInt(secondText.getText().toString());
}
if (minute != 0 || second != 0) {
System.out.println(minute+":"+second);
ArrayList<Integer> list = new ArrayList<Integer>();
list.add(minute);
list.add(second);
Intent intent = new Intent(TimeOutActivity.this,StartActivity.class);
intent.putIntegerArrayListExtra("times", list);
startActivity(intent);
}
}
});
}
@Override
protected void onResume() {
minute = 0;
second = 0;
super.onResume();
}
}
(二)StartActivity
public class StartActivity extends Activity{
static int minute = -1;
static int second = -1;
TextView timeView;
Timer timer;
TimerTask timerTask;
Handler handler = new Handler(){
public void handleMessage(Message msg) {
System.out.println("handle!");
if (minute == 0) {
if (second == 0) {
timeView.setText("Time out !");
if (timer != null) {
timer.cancel();
timer = null;
}
if (timerTask != null) {
timerTask = null;
}
}else {
second--;
if (second >= 10) {
timeView.setText("0"+minute + ":" + second);
}else {
timeView.setText("0"+minute + ":0" + second);
}
}
}else {
if (second == 0) {
second =59;
minute--;
if (minute >= 10) {
timeView.setText(minute + ":" + second);
}else {
timeView.setText("0"+minute + ":" + second);
}
}else {
second--;
if (second >= 10) {
if (minute >= 10) {
timeView.setText(minute + ":" + second);
}else {
timeView.setText("0"+minute + ":" + second);
}
}else {
if (minute >= 10) {
timeView.setText(minute + ":0" + second);
}else {
timeView.setText("0"+minute + ":0" + second);
}
}
}
}
};
};
@Override
protected void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_NO_TITLE);
super.onCreate(savedInstanceState);
setContentView(R.layout.start);
timeView = (TextView)findViewById(R.id.myTime);
if (minute == -1 && second == -1) {
Intent intent = getIntent();
ArrayList<Integer> times = intent.getIntegerArrayListExtra("times");
minute = times.get(0);
second = times.get(1);
}
timeView.setText(minute + ":" + second);
timerTask = new TimerTask() {
@Override
public void run() {
Message msg = new Message();
msg.what = 0;
handler.sendMessage(msg);
}
};
timer = new Timer();
timer.schedule(timerTask,0,1000);
}
@Override
protected void onDestroy() {
if (timer != null) {
timer.cancel();
timer = null;
}
if (timerTask != null) {
timerTask = null;
}
minute = -1;
second = -1;
super.onDestroy();
}
}
展示效果:
一个小小的提醒,做设计的人不应该和做执行的人多接触;设计要的是天马行空,完美;而做实际的人一直在克服难题,总是在不断超越中。若是可以和设计谈判,那么执行就没有那么背水一战!