请尝试以下代码。它将解决您的问题。
请按照以下步骤操作。
1) Make one BaseActivity Class.
2) Make One MainActivity Class and extend BaseActivity.
3) Make another SecondActivity class and extend BaseActivity.
在这里，我发布了您需要的所有课程。
我在 BaseActivity 做什么？
我创建了一个名为 MyCount 的 Countdown Timer 类，它将显示剩余时间。我创建了一个默认设置为 false 的布尔标志。因此，当用户调用 BaseActivity 的 setHeading() 函数时，它将检查 falg 是否为假，然后启动计时器，如果为真，则再次设置计时器并再次启动。
基本活动
import android.app.Activity;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.widget.TextView;
public abstract class BaseActivity extends Activity
{
private TextView textView = null;
public static MyCount counter = null;
private static boolean flag = false;
private static long millisUntilFinishedVariable = 0;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
}
protected void setHeading(String message)
{
if(textView == null)
{
textView = (TextView)findViewById(R.id.textView);
if(textView != null)
textView.setText(message);
if(flag == false)
{
counter = new MyCount(30000, 1000);
counter.start();
}
else
{
counter.cancel();
counter = new MyCount(millisUntilFinishedVariable, 1000);
counter.start();
}
}
}
// countdowntimer is an abstract class, so extend it and fill in methods
public class MyCount extends CountDownTimer
{
public MyCount(long millisInFuture, long countDownInterval)
{
super(millisInFuture, countDownInterval);
}
@Override
public void onFinish()
{
textView.setText("done!"); //TextView object should be defined in onCreate
flag = false;
}
@Override
public void onTick(long millisUntilFinished)
{
millisUntilFinishedVariable = millisUntilFinished;
flag = true;
textView.setText("Left:" + millisUntilFinished/1000);// This will be called every Second.
}
}
}
主要活动
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends BaseActivity
{
private Button buttonClick = null;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setHeading("Text From Main Activity");
buttonClick = (Button)findViewById(R.id.buttonClick);
buttonClick.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View arg0)
{
startActivityForResult(new Intent(MainActivity.this,SecondActivity.class), 0);
}
});
}
}
activity_main.xml
<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" >
<include layout="@layout/header"/>
<Button
android:id="@+id/buttonClick"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="96dp"
android:layout_marginTop="68dp"
android:text="Second Activity" />
</RelativeLayout>
第二活动
import android.os.Bundle;
public class SecondActivity extends BaseActivity
{
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.second_activity);
setHeading("From Second Activity");
}
}
second_activity.xml
<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" >
<include layout="@layout/header"/>
</RelativeLayout>
header.xml
<?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" >
<TextView
android:id="@+id/textView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="18.0sp"/>
</LinearLayout>