android 计时器

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
android:orientation="vertical" >

<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_margin="10dip"
android:orientation="horizontal" >

<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="4"
android:gravity="center"
android:text="设置时间:" />

<EditText
android:id="@+id/edt_settime"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:inputType="number" />
</LinearLayout>

<Chronometer
android:id="@+id/chronometer"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#ff0000"
android:textSize="60dip" />

<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_margin="10dip"
android:orientation="horizontal" >

<Button
android:id="@+id/btntimeopp"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="开始记时" />

<Button
android:id="@+id/btnReset"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="重置" />
</LinearLayout>

</LinearLayout>

package com.example.yanlei.yl;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.os.SystemClock;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Chronometer;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

// 设置初始时间
private int startTime = 0;
// 声明计时器Chronomete对象
private Chronometer chronometer;
// 定义计时器操作按钮
private Button btnOperate;
// 定义计时器重置按钮
private Button btnRest;
// 定义到达时间的edittext
private EditText edtSetTime;
// 开始boolOperate=true,停止boolOperate=false
private Boolean boolOperate = true;

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// 得到布局中的所有对象
findView();
// 设置对象的监听器
setListener();
}

// 得到布局中的所有对象
private void findView() {
// TODO Auto-generated method stub
chronometer = (Chronometer) findViewById(R.id.chronometer);
btnOperate = (Button) findViewById(R.id.btntimeopp);
btnRest = (Button) findViewById(R.id.btnReset);
edtSetTime = (EditText) findViewById(R.id.edt_settime);
}

// 得到布局中的所有对象
private void setListener() {
// TODO Auto-generated method stub
btnRest.setOnClickListener(listener);
btnOperate.setOnClickListener(listener);
chronometer
.setOnChronometerTickListener(new Chronometer.OnChronometerTickListener() {
@Override
public void onChronometerTick(Chronometer chronometer) {
// 如果开始计时到现在超过了startime秒
if (SystemClock.elapsedRealtime()
- chronometer.getBase() > startTime * 1000) {
// 计时器停止
chronometer.stop();
// 给用户提示
showDialog();
}
}
});
}

OnClickListener listener = new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
// 开始按钮
case R.id.btntimeopp:
// 如果boolOperate==true,说明计时开始
if (boolOperate) {
String ss = edtSetTime.getText().toString();
// 把到达时间转化为Int类型
if (!(ss.equals("") && ss != null)) {
startTime = Integer.parseInt(edtSetTime.getText()
.toString());
}
// 设置开始时间
chronometer.setBase(SystemClock.elapsedRealtime());
// 开始记时
chronometer.start();
boolOperate = false;
// eidttext不可点
edtSetTime.setClickable(false);
btnOperate.setText("点击停止");
}
// 如果boolOperate==false,说明计时结束
else {
// 计时停止
chronometer.stop();
boolOperate = true;
// eidttex可点
edtSetTime.setClickable(true);
btnOperate.setText("点击开始");
}

break;
// 重置按钮
case R.id.btnReset:
chronometer.setBase(SystemClock.elapsedRealtime());
break;
default:
break;
}
}
};

protected void showDialog() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setIcon(R.drawable.ic_launcher);
builder.setTitle("闫磊温馨提醒你").setMessage("设置："+startTime+"秒，时间到了")
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
});

AlertDialog dialog = builder.create();
dialog.show();
}
}