在mainactivity.java中的项目中，我有：
public class MainActivity extends ActionBarActivity
{
private static final int MY_DATA_CHECK_CODE = 0;
public static MainActivity currentActivity;
TextToSpeech mTts;
private String targetURL;
private String urlParameters;
private Button btnClick;
private String clicking = "clicked";
private String[] ipaddresses = new String[]{
"http://192.168.1.10:8098/?cmd=nothing"};
private String iptouse = "";
private TextView text;
private boolean connectedtoipsuccess = false;
private int counter = 0;
private NotificationCompat.Builder mbuilder;
private Timer timer = new Timer();
private TextView text1, text2, text3;
private long starttime = 0;
private TimerCounter tc;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tc = new TimerCounter();
}
}
在TimerCounter类中，我有：
package com.test.webservertest;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.SystemClock;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.util.Timer;
public class TimerCounter extends Activity
{
private Button startButton;
private Button pauseButton;
private TextView timerValue;
private long startTime = 0L;
private Handler customHandler = new Handler();
long timeInMilliseconds = 0L;
long timeSwapBuff = 0L;
long updatedTime = 0L;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
timerValue = (TextView) findViewById(R.id.timerValue);
startButton = (Button) findViewById(R.id.startButton);
startButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
startTime = SystemClock.uptimeMillis();
customHandler.postDelayed(updateTimerThread, 0);
}
});
pauseButton = (Button) findViewById(R.id.pauseButton);
pauseButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
timeSwapBuff += timeInMilliseconds;
customHandler.removeCallbacks(updateTimerThread);
}
});
}
private Runnable updateTimerThread = new Runnable() {
public void run() {
timeInMilliseconds = SystemClock.uptimeMillis() - startTime;
updatedTime = timeSwapBuff + timeInMilliseconds;
int secs = (int) (updatedTime / 1000);
int mins = secs / 60;
secs = secs % 60;
int milliseconds = (int) (updatedTime % 1000);
timerValue.setText("" + mins + ":"
+ String.format("%02d", secs) + ":"
+ String.format("%03d", milliseconds));
customHandler.postDelayed(this, 0);
}
};
}
这是资源按钮和文本视图的XML文件代码：
<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"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context=".MainActivity">
<TextView
android:text="WEBSERVER"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:textSize="50dp"
android:textColor="#FFF"
android:id="@+id/textView"/>
<TextView
android:id="@+id/textView1"
android:gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="35dp"
android:textSize="18sp"
android:textColor="#ff0000"
android:text="HttpURLConnection\nIP Based" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Checking Connection.."
android:layout_above="@+id/textView"
android:layout_centerHorizontal="true"
android:layout_marginBottom="47dp"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Check Ip"
android:id="@+id/checkipbutton"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="61dp"/>
<TextView
android:id="@+id/timerValue"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:textSize="40sp"
android:textColor="#000000"
android:layout_marginTop="90dp"
android:text="@string/timerVal" />
<Button
android:id="@+id/startButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_marginLeft="20dp"
android:layout_marginTop="170dp"
android:text="startButtonLabel" />
<Button
android:id="@+id/pauseButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="pauseButtonLabel"
android:layout_alignParentRight="true"
android:layout_marginTop="170dp"/>
</RelativeLayout>
底部的文本视图和两个按钮用于使用计时器计数器。
然后是strings.xml文件：
<resources>
<string name="app_name">WebServerTest</string>
<string name="hello_world">Hello world!</string>
<string name="action_settings">Settings</string>
<string name="title_activity_activity_motion_event">activity_motion_event</string>
<string name="status1_string">Touch One Status</string>
<string name="title_activity_activity__motion">Activity_Motion</string>
<string name="status_string">Touch One Status</string>
<string name="timerVal">00:00:00</string>
<string name="pauseButtonLabel">Pause</string>
<string name="startButtonLabel">Start</string>
</resources>
我没有收到任何ERORR或异常，但当我运行我的程序并单击开始按钮时，什么也不会发生。
最佳答案
有不同的原因可以解释为什么您的应用程序不能按预期运行。
首先，TimerCounter类扩展活动。当调用tc=new timercounter（）时，可能正在尝试启动timercounter活动。如果你想达到这个目的，你必须使用android的意图并启动它
Intent i = new Intent(this, TimerCounter.class);
startActivity(i);
您还应该在manifest.xml中声明您的活动：
<activity
android:name="com.test.webservertest.TimerCounter"
android:label="@string/app_name"
/>
你可能被两个活动具有相同的布局（r.layout.activity_main）这一事实所愚弄。所以当你点击按钮时，你仍然在你的主活动中，而不是在TimerCounter活动中。
然后，要优化计时器，可以使用与计时器关联的timer任务。