本文实例为大家分享了chronometer实现倒计时功能，android提供了实现按照秒计时的api，供大家参考，具体内容如下

一、自定义chronometerview 继续自textview

主要原理：先设置一个基准倒计时时间mbaseseconds，内置handler 每隔1s发送一个空消息，mremainseconds--，同时刷新界面视图，回调给外部调用者，只到为零。外部调用者可通过start()/pause()/stop()来控制计时器的工作状态。

可以app中发送短信验证码的场景为例，做了一个很粗糙的界面，但功能都实现了。

/**

* @name 倒计时器(类似妙表倒数计时，支持暂停、停止、重新开始)

* @author fanjb

* @date 2015年11月6日

*/

public class chronometerview extends textview {

/**

* a callback that notifies when the chronometer has decremented on its own.

*

* @author fanjb

*/

public interface ontickchangelistener {

/**

* remain seconds changed

*

* @param view

* @param remainseconds

*/

public void ontickchanged(chronometerview view, long remainseconds);

}

private long mbase;

private long mremainseconds;

private boolean mstarted;

private boolean mrestart;

private boolean mvisible;

private boolean misenable;

private ontickchangelistener mticklistener;

public chronometerview(context context) {

this(context, null);

}

public chronometerview(context context, attributeset attrs) {

super(context, attrs, 0);

}

public chronometerview(context context, attributeset attrs, int defstyleattr) {

super(context, attrs, defstyleattr);

updatetext(mremainseconds);

}

@override

protected void onwindowvisibilitychanged(int visibility) {

super.onwindowvisibilitychanged(visibility);

mvisible = visibility == visible;

updatestatus();

}

@override

protected void ondetachedfromwindow() {

super.ondetachedfromwindow();

mvisible = false;

updatestatus();

}

/**

* 启动计时器

*/

public void start() {

if (mrestart && !mstarted) {

mremainseconds = mbase;

}

mstarted = true;

updatestatus();

}

/**

* 暂停计时器

*/

public void pause() {

if (mstarted) {

mstarted = mrestart = false;

updatestatus();

}

}

/**

* 停止计时器，再次调用 start()重新启动

*/

public void stop() {

mstarted = false;

mrestart = true;

updatestatus();

updatetext(mremainseconds = 0);

dispatchticklistener();

}

/**

* 刷新内部状态

*/

private void updatestatus() {

boolean isenable = mvisible && mstarted;

if (misenable != isenable) {

if (isenable) {

mhandler.sendmessage(message.obtain(mhandler, tick_what));

} else {

mhandler.removemessages(tick_what);

}

misenable = isenable;

}

}

private static final int tick_what = 1;

private handler mhandler = new handler() {

public void handlemessage(android.os.message msg) {

if (mremainseconds > 0) {

updatetext(--mremainseconds);

dispatchticklistener();

sendmessagedelayed(message.obtain(this, tick_what), 1000);

}

}

};

private void updatetext(long now) {

string text = dateutils.formatelapsedtime(now);

settext(text);

}

/**

* 在未启动状态下设置开始倒计时时间

*

* @param baseseconds

*/

public void setbaseseconds(long baseseconds) {

if (baseseconds > 0 && baseseconds != mbase && !mstarted) {

mbase = mremainseconds = baseseconds;

updatetext(mremainseconds);

}

}

/**

* 剩余时间

*

* @return

*/

public long getremainseconds() {

return mremainseconds;

}

public void setontickchangelistener(ontickchangelistener listener) {

mticklistener = listener;

}

public ontickchangelistener getticklistener() {

return mticklistener;

}

private void dispatchticklistener() {

if (mticklistener != null) {

mticklistener.ontickchanged(this, getremainseconds());

}

}

@override

public void oninitializeaccessibilityevent(accessibilityevent event) {

super.oninitializeaccessibilityevent(event);

event.setclassname(chronometerview.class.getname());

}

@override

public void oninitializeaccessibilitynodeinfo(accessibilitynodeinfo info) {

super.oninitializeaccessibilitynodeinfo(info);

info.setclassname(chronometer.class.getname());

}

}

二、xml 中没有加入自定义的控件属性，同textview

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:orientation="horizontal" >

android:id="@+id/chronometer_view"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_marginleft="5dp"

android:background="@drawable/chronometer_view_bg"

android:enabled="true"

android:text="00:00" />

android:id="@+id/start_chronometer_view_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_marginleft="5dp"

android:text="start" />

android:id="@+id/pause_chronometer_view_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_marginleft="5dp"

android:text="pause" />

android:id="@+id/stop_chronometer_view_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_marginleft="5dp"

android:text="stop" />

三、在activity中做一个简单的测试(可以发送短信验证码的实际应用场景为例)

public class chronometeractivity extends activity {

private chronometerview mchronometerview;

@override

protected void oncreate(bundle savedinstancestate) {

super.oncreate(savedinstancestate);

setcontentview(r.layout.activity_clock);

// 自定义计时器

if (mchronometerview == null) {

mchronometerview = (chronometerview) findviewbyid(r.id.chronometer_view);

mchronometerview.setbaseseconds(60);

mchronometerview.setontickchangelistener(new ontickchangelistener() {

@override

public void ontickchanged(chronometerview view, long curtimemills) {

system.out.println(curtimemills);

view.setenabled(curtimemills == 0 || curtimemills == 60);

if (curtimemills == 0) {

mchronometerview.settext("重新发送");

}

}

});

mchronometerview.settext("点击发送验证码");

}

findviewbyid(r.id.start_chronometer_view_btn).setonclicklistener(mclicklistener);

findviewbyid(r.id.pause_chronometer_view_btn).setonclicklistener(mclicklistener);

findviewbyid(r.id.stop_chronometer_view_btn).setonclicklistener(mclicklistener);

}

private view.onclicklistener mclicklistener = new onclicklistener() {

@override

public void onclick(view v) {

switch (v.getid()) {

case r.id.start_chronometer_view_btn:

if (mchronometerview != null) {

mchronometerview.start();

}

break;

case r.id.pause_chronometer_view_btn:

if (mchronometerview != null) {

mchronometerview.pause();

}

break;

case r.id.stop_chronometer_view_btn:

if (mchronometerview != null) {

mchronometerview.stop();

}

break;

}

}

};

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持萬仟网。