停止观看逻辑

我想在android中开发一个简单的秒表逻辑。

单击列表视图时,计时器应该启动,单击按钮时计时器应该停止。 任何人都可以指导我。 任何示例代码都会有很大帮助

Solutions Collecting From Web of "停止观看逻辑"

使用秒表类(为了更高精度使用System.nanoTime()

在Button Presses上添加Start()事件和Stop()事件。 您需要更新UI,以便使用线程/处理程序组合。

这应该让你开始。

编辑:添加代码。 (很棒的运动!:))

使用Refresh_Rate配置UI的更新频率。

 import android.app.Activity; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; public class Main extends Activity implements OnClickListener{ final int MSG_START_TIMER = 0; final int MSG_STOP_TIMER = 1; final int MSG_UPDATE_TIMER = 2; Stopwatch timer = new Stopwatch(); final int REFRESH_RATE = 100; Handler mHandler = new Handler() { @Override public void handleMessage(Message msg) { super.handleMessage(msg); switch (msg.what) { case MSG_START_TIMER: timer.start(); //start timer mHandler.sendEmptyMessage(MSG_UPDATE_TIMER); break; case MSG_UPDATE_TIMER: tvTextView.setText(""+ timer.getElapsedTime()); mHandler.sendEmptyMessageDelayed(MSG_UPDATE_TIMER,REFRESH_RATE); //text view is updated every second, break; //though the timer is still running case MSG_STOP_TIMER: mHandler.removeMessages(MSG_UPDATE_TIMER); // no more updates. timer.stop();//stop timer tvTextView.setText(""+ timer.getElapsedTime()); break; default: break; } } }; TextView tvTextView; Button btnStart,btnStop; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); tvTextView = (TextView)findViewById(R.id.TextView01); btnStart = (Button)findViewById(R.id.Button01); btnStop= (Button)findViewById(R.id.Button02); btnStart.setOnClickListener(this); btnStop.setOnClickListener(this); } public void onClick(View v) { if(btnStart == v) { mHandler.sendEmptyMessage(MSG_START_TIMER); }else if(btnStop == v){ mHandler.sendEmptyMessage(MSG_STOP_TIMER); } } } 

正如st0le通过使用Stopwatch类给出了一个很好的例子。 我稍微修改了这个类,并添加了一些方法。

 /* Copyright (c) 2005, Corey Goldberg StopWatch.java is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Modified: Bilal Rabbani bilalrabbani1@live.com (Nov 2013) */ package bilalrabbani1.at.live.com; public class Stopwatch { private long startTime = 0; private boolean running = false; private long currentTime = 0; public void start() { this.startTime = System.currentTimeMillis(); this.running = true; } public void stop() { this.running = false; } public void pause() { this.running = false; currentTime = System.currentTimeMillis() - startTime; } public void resume() { this.running = true; this.startTime = System.currentTimeMillis() - currentTime; } //elaspsed time in milliseconds public long getElapsedTimeMili() { long elapsed = 0; if (running) { elapsed =((System.currentTimeMillis() - startTime)/100) % 1000 ; } return elapsed; } //elaspsed time in seconds public long getElapsedTimeSecs() { long elapsed = 0; if (running) { elapsed = ((System.currentTimeMillis() - startTime) / 1000) % 60; } return elapsed; } //elaspsed time in minutes public long getElapsedTimeMin() { long elapsed = 0; if (running) { elapsed = (((System.currentTimeMillis() - startTime) / 1000) / 60 ) % 60; } return elapsed; } //elaspsed time in hours public long getElapsedTimeHour() { long elapsed = 0; if (running) { elapsed = ((((System.currentTimeMillis() - startTime) / 1000) / 60 ) / 60); } return elapsed; } public String toString() { return getElapsedTimeHour() + ":" + getElapsedTimeMin() + ":" + getElapsedTimeSecs() + "." + getElapsedTimeMili(); } } 

问候

很好的例子,以防万一有人想要这个布局文件(尽管很简单)。

        

在Nexus-5上编译

基于IntentService,没有非SDK依赖项和单个文件

 import android.app.Activity; import android.app.IntentService; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.os.Bundle; import android.os.Handler; import android.support.v4.content.LocalBroadcastManager; import android.util.Log; import android.view.View; import android.widget.Button; import android.widget.LinearLayout; import android.widget.TextView; public class Main extends Activity { static final String BROADCAST_ACTION = "com.cirosantilli.android_cheat.intent_service_text_view.BROADCAST"; static final String EXTENDED_DATA_STATUS = "com.cirosantilli.android_cheat.intent_service_text_view.BROADCAST"; static final String TAG = "com.cirosantilli"; private int i = 0; @Override protected void onCreate(Bundle savedInstanceState) { Log.d(TAG, "onCreate"); super.onCreate(savedInstanceState); final LinearLayout linearLayout = new LinearLayout(this); Button button; final Intent intent = new Intent(Main.this, MyService.class); button = new Button(this); button.setText("start service"); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Log.d(TAG, "start button"); Main.this.startService(intent.putExtra(Main.EXTENDED_DATA_STATUS, Main.this.i)); } }); linearLayout.addView(button); button = new Button(this); button.setText("stop service"); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Log.d(TAG, "stop button"); Main.this.stopService(intent); } }); linearLayout.addView(button); final TextView textView = new TextView(this); textView.setText(Integer.toString(i)); linearLayout.addView(textView); this.setContentView(linearLayout); LocalBroadcastManager.getInstance(this).registerReceiver( new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { Main.this.i = intent.getIntExtra(Main.EXTENDED_DATA_STATUS, 0); textView.setText(Integer.toString(Main.this.i)); } }, new IntentFilter(Main.BROADCAST_ACTION) ); } public static class MyService extends IntentService { private Handler mHandler; private int i = 1; private boolean done; public MyService() { super("MyService"); } @Override protected void onHandleIntent(Intent intent) { Log.d(TAG, "onHandleIntent"); this.i = intent.getIntExtra(Main.EXTENDED_DATA_STATUS, 0); this.done = false; while(!done) { Log.d(TAG, "while true"); try { Thread.sleep(1000); } catch (InterruptedException e) { Thread.currentThread().interrupt(); } LocalBroadcastManager.getInstance(this).sendBroadcast( new Intent(Main.BROADCAST_ACTION) .putExtra(Main.EXTENDED_DATA_STATUS, MyService.this.i)); this.i++; } } @Override public void onDestroy() { Log.d(TAG, "onDestroy"); this.done = true; super.onDestroy(); } } } 

仅用于低精度。 我们可以通过在onHandleIntent使用System.currentTimeMillis而不是使用整数值来提高精度,并减少hibernate时间以减少延迟。

在Android 22上测试。 这里标准构建样板。

您只需使用文本视图作为计时器,而使用3个按钮进行停止启动和重置,而不是使用列表视图。 使用这些可以相应地生成java代码