Android三种实现定时器的方法
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2024-01-01 12:26:28
方法一、使用handler和thread（线程）实现定时器
复制代码 代码如下:
package com.xunfang.handerdemo;
import and...
方法一、使用handler和thread（线程）实现定时器
复制代码 代码如下:
package com.xunfang.handerdemo;
import android.app.activity;
import android.os.bundle;
import android.os.handler;
import android.os.message;
import android.widget.textview;
public class handerdemoactivity extends activity {
textview tvshow;
private int i = 0;
@override
public void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.main);
tvshow = (textview) findviewbyid(r.id.tv_show);
new thread(new threadshow()).start();
}
// handler类接收数据
handler handler = new handler() {
public void handlemessage(message msg) {
if (msg.what == 1) {
tvshow.settext(integer.tostring(i++));
system.out.println("receive....");
}
};
};
// 线程类
class threadshow implements runnable {
@override
public void run() {
while (true) {
try {
thread.sleep(1000);
message msg = new message();
msg.what = 1;
handler.sendmessage(msg);
system.out.println("send...");
} catch (exception e) {
e.printstacktrace();
system.out.println("thread error...");
}
}
}
}
}
方法二、使用handler类自带的postdelyed实现定时器
复制代码 代码如下:
package com.xunfang.handerdemo;
import android.app.activity;
import android.os.bundle;
import android.os.handler;
import android.widget.textview;
public class handerdemoactivity extends activity {
textview tvshow;
private int i = 0;
private int time = 1000;
@override
public void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.main);
tvshow = (textview) findviewbyid(r.id.tv_show);
handler.postdelayed(runnable, time); //每隔1s执行
}
handler handler = new handler();
runnable runnable = new runnable() {
@override
public void run() {
// handler自带方法实现定时器
try {
handler.postdelayed(this, time);
tvshow.settext(integer.tostring(i++));
system.out.println("do...");
} catch (exception e) {
// todo auto-generated catch block
e.printstacktrace();
system.out.println("exception...");
}
}
};
}
方法三、使用handler、timer和timertask三个android类实现定时器
复制代码 代码如下:
package com.xunfang.handerdemo;
import java.util.timer;
import java.util.timertask;
import android.app.activity;
import android.os.bundle;
import android.os.handler;
import android.os.message;
import android.widget.textview;
public class handerdemoactivity extends activity {
textview tvshow;
private int i = 0;
private int time = 1000;
@override
public void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.main);
tvshow = (textview) findviewbyid(r.id.tv_show);
timer.schedule(task, 1000, 1000); // 1s后执行task,经过1s再次执行
}
handler handler = new handler() {
public void handlemessage(message msg) {
if (msg.what == 1) {
tvshow.settext(integer.tostring(i++));
}
super.handlemessage(msg);
};
};
timer timer = new timer();
timertask task = new timertask() {
@override
public void run() {
// 发送消息
message message = new message();
message.what = 1;
handler.sendmessage(message);
}
};
}