Android实战第一篇——时钟+闹钟+计时器+秒表

学习了快一学期的Android了,之前的知识点都是零散的学习的,只有当我们真正的去把他们用起来的时候才会发现难点,自己才会独立尝试去解决某个问题。接下来是我的一个简单的多功能时钟的小实战(视频资源https://pan.baidu.com/s/1mL8VUVC-9W9lO6IEpobDZg 密码:2ajv)

具体的效果可以参考手机上的时钟。

 

首先我们来看一看布局文件layout_main.xml

 

我们总的来看一下整个布局

 



    

        

            
            

            

                
                

                
		……
                

                
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整个布局整的是一个FrameLayout,我们在里面放了一个TabHost,接下来我们就可以在里面直接添加自己想要的布局了,可能初学者初一看会有那么一个疑问,就是这个是什么东西??这是一个自定义的控件,我们创建的一个继承了LinearLayout的一个类(讲解可以参考这里http://blog.csdn.net/guozh/article/details/7662374),上面我们看到了四个这样的标签,表示我们有四个这样的Tab页面。关于布局的东西这里就不多讲了,之后会把我自己在学习过程中的一些不懂,以及相关的知识点上传到资源中,大家可以下载来看看。

 

这是完整的布局文件代码

 



    

        

            
            

            

                

                    
                

                

                    
                    

                    
                

                

                    

                        

                        

                        

                        

                        
                    

                    

                        

 

 

讲完了布局,我们来讲讲MainActivity

 

	private TabHost tabHost;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		tabHost = (TabHost) findViewById(android.R.id.tabhost);
		tabHost.setup();

		// 为TabHost添加标签
		// 新建一个newTabSpec(newTabSpec)用来指定该标签的id(就是用来区分标签)的
		// 设置其标签和图表(setIndicator)
		// 设置内容(setContent)
		/*
		 * 设置选项卡 : -- 设置按钮名称 : setIndicator(时钟); -- 设置选项卡内容 : setContent(),
		 * 可以设置视图组件, 可以设置Activity, 也可以设置Fragement;
		 */
		tabHost.addTab(tabHost.newTabSpec("tabTime").setIndicator("时钟")
				.setContent(R.id.tabTime));
		tabHost.addTab(tabHost.newTabSpec("tabAlarm").setIndicator("闹钟")
				.setContent(R.id.tabAlarm));
		tabHost.addTab(tabHost.newTabSpec("tabTimer").setIndicator("计时器")
				.setContent(R.id.tabTimer));
		tabHost.addTab(tabHost.newTabSpec("tabStopWatch").setIndicator("秒表")
				.setContent(R.id.tabStopWatch));
	}

 

 

在MainActivity中主要的操作就是设置TabHost,上面的代码中已经贴上了解释,这里就不讲了,接着我们就重点来讲讲时钟、闹钟、计时器和秒表这四部分。

一、时钟

在布局文件中我们看到,界面上只有一个TextView,这个TextView的作用就是显示一个系统的当前时间,同时这个时间还是一秒一秒跳的,要实现一秒一秒的跳就需要我们每隔一秒就要刷新一下,同时我们这里还考虑了切换到另一个Tab的时候,这个时间就不跳动了,这样就会减少这个对系统的占用,考虑到了这点我们在这里用到了Handler,通过handler发送的msg.what 来判断是否要刷新时间。

 

public class TimeView extends LinearLayout {

	private TextView tvTime;
	public TimeView(Context context) {
		super(context);
	}

	public TimeView(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	public TimeView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
	}

	@Override
	protected void onFinishInflate() {
		super.onFinishInflate();
		tvTime = (TextView) findViewById(R.id.tvTime);
		//tvTime.setText("hello");
		
		timeHandler.sendEmptyMessage(0);
	}
	
	@Override
	protected void onVisibilityChanged(View changedView, int visibility) {
		super.onVisibilityChanged(changedView, visibility);
		//当再次切换到这个Tab时我们就再发送一次这个消息,否者就把所有的消息移除掉
		if (visibility == View.VISIBLE) {
			timeHandler.sendEmptyMessage(0);			
		}else{
			timeHandler.removeMessages(0);
		}
	}
	
	private void refreshTime(){
		//获取当前的时间
		Calendar c = Calendar.getInstance();
		
		tvTime.setText(String.format("%d:%d:%d", c.get(Calendar.HOUR_OF_DAY),c.get(Calendar.MINUTE),c.get(Calendar.SECOND)));
	}
	private Handler timeHandler = new Handler(){
		public void handleMessage(android.os.Message msg) {
			refreshTime();
			
			//处于当前Tab的时候给自己发送信息,可以刷新
			if (getVisibility() == View.VISIBLE) {				
				//1秒钟后再次执行以下sendEmptyMessage,what参数用于区分不同的message
				timeHandler.sendEmptyMessageDelayed(0, 1000);
			}
		};
	};
}

 

其实这里的Handler可以用Timer来完成亦可以达到同样的效果。

在这里要提一下的是onFinishInflate(),这在我们自定义布局的时候一定要用到的,解释以及例子在之后上传的知识点中同样有,看看那个就可以了。

二、闹钟

从第二个布局中我们可以看到,我们在这里用到了一个ListView,这是用来存储我们添加的闹钟的,既然这里用到了ListView,那么我们接着就会想到要给这个ListView一个适配器adapter,因此我们会在这里创建这么一个适配器,

 

private ArrayAdapter adapter;

看到这里可能又会有疑问了,AlarmData这是个什么东西?有这么一个数据类型吗??其实这里我们自定义了一个数据类型,用来专门存储一下创建的闹钟时间。我们来看一下自定义的数据类型代码吧!

 

 

// 自定义数据类型
	private static class AlarmData {
		private long time = 0;
		private Calendar date;
		private String timeLabel = "";

		public AlarmData(long time) {
			this.time = time;
			date = Calendar.getInstance();
			date.setTimeInMillis(time);
			timeLabel = String.format("%d月%d日   %d:%d",
					date.get(Calendar.MONTH) + 1,
					date.get(Calendar.DAY_OF_MONTH),
					date.get(Calendar.HOUR_OF_DAY), date.get(Calendar.MINUTE));
		}

		public long getTime() {
			return time;
		}

		public String getTimeLabel() {
			return timeLabel;
		}

		public int getId() {
			return (int) (getTime() / 1000 / 60);
		}

		@Override
		public String toString() {
			return getTimeLabel();
		}

	}


这个数据类型的代码其实还是很容易明白的,不多讲了。

 

当我们到这里的时候,我们其实还没有真正的完成,假如我们的代码已经写好了,并且可以运行了我们运行一次后,并且添加了N个闹钟,当我们退出程序,再次打开就会发现,我们之前创建的闹钟都没了,原因是我们虽然把数据临时的保存在了ListView中,但是我们并没有长时间的保存,因此我们接着就来讲讲长久的保存这些闹钟数据。

private void saveAlarmList() {
		Editor editor = getContext().getSharedPreferences(
				AlarmView.class.getName(), Context.MODE_PRIVATE).edit();

		StringBuffer sb = new StringBuffer();

		for (int i = 0; i < adapter.getCount(); i++) {
			sb.append(adapter.getItem(i).getTime()).append(",");
		}
		if (sb.length() > 1) {
			String content = sb.toString().substring(0, sb.length() - 1);
			editor.putString(KEY_ALARM_LIST, content);

			System.out.println(content);
		} else {
			editor.putString(KEY_ALARM_LIST, null);
		}
		editor.commit();
	}

有了保存,我们当然的会想到读取

 

 

private void readSaveAlarmList() {
		SharedPreferences sp = getContext().getSharedPreferences(
				AlarmView.class.getName(), Context.MODE_PRIVATE);
		String content = sp.getString(KEY_ALARM_LIST, null);

		if (content != null) {
			String[] timeStrings = content.split(",");
			for (String string : timeStrings) {
				adapter.add(new AlarmData(Long.parseLong(string)));
			}
		}
	}

上面的一些陌生的类型在之后的知识点中可以查看。

接着我们来看看最关键的就是添加闹钟

 

 

private void addAlarm() {

		Calendar c = Calendar.getInstance();

		new TPDiolog(getContext(), new TimePickerDialog.OnTimeSetListener() {

			@Override
			public void onTimeSet(TimePicker view, int hourOfDay, int minute) {

				Calendar calendar = Calendar.getInstance();
				calendar.set(Calendar.HOUR_OF_DAY, hourOfDay);
				calendar.set(Calendar.MINUTE, minute);
				calendar.set(Calendar.SECOND, 0);
				calendar.set(Calendar.MILLISECOND, 0);

				Calendar currentTime = Calendar.getInstance();
				if (currentTime.getTimeInMillis() >= calendar.getTimeInMillis()) {
					calendar.setTimeInMillis(calendar.getTimeInMillis() + 24
							* 60 * 60 * 1000);
				}
				AlarmData ad = new AlarmData(calendar.getTimeInMillis());
				adapter.add(ad);
				alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,
						ad.getTime(), 5 * 60 * 1000, PendingIntent
								.getBroadcast(getContext(), ad.getId(),
										new Intent(getContext(),
												AlarmReceiver.class), 0));
				saveAlarmList();
			}
		}, c.get(Calendar.HOUR_OF_DAY), c.get(Calendar.MINUTE), true).show();
	}

这里我们可以看到TPDiolog这个,当你自己尝试过后可能也会遇到同样的问题,那就是当你通过TimePickerDialog这个系统的时间选择控件的时候,点击确定后,会创建两条记录,这是因为我们点击确定后会调用该事件监听器的时间,在关闭这个Dialog的时候也会调用一次,所以我们在这里自己重写了一下该类的方法

 

 

TPDiolog.class

 

public class TPDiolog extends TimePickerDialog {

	public TPDiolog(Context context, OnTimeSetListener callBack, int hourOfDay,
			int minute, boolean is24HourView) {
		super(context, callBack, hourOfDay, minute, is24HourView);
	}

	//重写该方法是为了避免调用两次onTimeSet
	//可以参考 该网址http://www.68idc.cn/help/buildlang/ask/20150206210559.html
	@Override
	protected void onStop() {
		//super.onStop();
	}
}

 

在之前的代码中我们还看到了一个alarmManager这一对象,这是我们为了调用系统的闹钟服务创建的实例,我们也因此而创建了一个AlarmReceiver.class

 

 

public class AlarmReceiver extends BroadcastReceiver {

	@Override
	public void onReceive(Context context, Intent arg1) {
		System.out.println("闹钟执行了!");
		
		AlarmManager am=(AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
		am.cancel(PendingIntent.getBroadcast(context, getResultCode(), new Intent(context, AlarmReceiver.class), 0));
		
		Intent i =new Intent(context,PlayAlarmAty.class);
		//设置intent的启动模式
		i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
		context.startActivity(i);
	}

}


一些小的地方讲好了,最后把AlarmView.class的完整代码贴上。

 

 

package com.example.clock;

import java.util.Calendar;
import java.util.Date;
import java.util.Iterator;

import android.app.AlarmManager;
import android.app.AlertDialog;
import android.app.PendingIntent;
import android.app.TimePickerDialog;
import android.app.TimePickerDialog.OnTimeSetListener;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.util.AttributeSet;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.Switch;
import android.widget.TimePicker;

public class AlarmView extends LinearLayout {

	private Button btnAddAlarm;
	private ListView lvListAlarm;
	private ArrayAdapter adapter;
	private AlarmManager alarmManager;

	public AlarmView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		init();
	}

	public AlarmView(Context context, AttributeSet attrs) {
		super(context, attrs);
		init();
	}

	public AlarmView(Context context) {
		super(context);
		init();
	}

	private void init() {
		alarmManager = (AlarmManager) getContext().getSystemService(
				Context.ALARM_SERVICE);
	}

	@Override
	protected void onFinishInflate() {
		super.onFinishInflate();
		btnAddAlarm = (Button) findViewById(R.id.btnAddAlarm);
		lvListAlarm = (ListView) findViewById(R.id.lvListAlarm);

		adapter = new ArrayAdapter(getContext(),
				android.R.layout.simple_list_item_1);
		lvListAlarm.setAdapter(adapter);

		readSaveAlarmList();
		// adapter.add(new AlarmData(System.currentTimeMillis()));

		btnAddAlarm.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				addAlarm();
			}
		});
		// 长按某项删除
		lvListAlarm.setOnItemLongClickListener(new OnItemLongClickListener() {

			@Override
			public boolean onItemLongClick(AdapterView arg0, View arg1,
					final int position, long arg3) {

				new AlertDialog.Builder(getContext())
						.setTitle("操作选项")
						.setItems(new CharSequence[] { "删除", "删除1" },
								new DialogInterface.OnClickListener() {

									@Override
									public void onClick(DialogInterface dialog,
											int which) {
										switch (which) {
										case 0:
											deleteAlarm(position);
											break;

										default:
											break;
										}
									}
								}).setNegativeButton("取消", null).show();
				return true;
			}
		});
	}

	private void deleteAlarm(int position) {
		AlarmData ad = adapter.getItem(position);
		adapter.remove(ad);
		saveAlarmList();

		alarmManager.cancel(PendingIntent.getBroadcast(getContext(),
				ad.getId(), new Intent(getContext(), AlarmReceiver.class), 0));
	}

	private void addAlarm() {

		Calendar c = Calendar.getInstance();

		new TPDiolog(getContext(), new TimePickerDialog.OnTimeSetListener() {

			@Override
			public void onTimeSet(TimePicker view, int hourOfDay, int minute) {

				Calendar calendar = Calendar.getInstance();
				calendar.set(Calendar.HOUR_OF_DAY, hourOfDay);
				calendar.set(Calendar.MINUTE, minute);
				calendar.set(Calendar.SECOND, 0);
				calendar.set(Calendar.MILLISECOND, 0);

				Calendar currentTime = Calendar.getInstance();
				if (currentTime.getTimeInMillis() >= calendar.getTimeInMillis()) {
					calendar.setTimeInMillis(calendar.getTimeInMillis() + 24
							* 60 * 60 * 1000);
				}
				AlarmData ad = new AlarmData(calendar.getTimeInMillis());
				adapter.add(ad);
				alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,
						ad.getTime(), 5 * 60 * 1000, PendingIntent
								.getBroadcast(getContext(), ad.getId(),
										new Intent(getContext(),
												AlarmReceiver.class), 0));
				saveAlarmList();
			}
		}, c.get(Calendar.HOUR_OF_DAY), c.get(Calendar.MINUTE), true).show();
	}

	private static final String KEY_ALARM_LIST = "alarmlist";

	private void saveAlarmList() {
		Editor editor = getContext().getSharedPreferences(
				AlarmView.class.getName(), Context.MODE_PRIVATE).edit();

		StringBuffer sb = new StringBuffer();

		for (int i = 0; i < adapter.getCount(); i++) {
			sb.append(adapter.getItem(i).getTime()).append(",");
		}
		if (sb.length() > 1) {
			String content = sb.toString().substring(0, sb.length() - 1);
			editor.putString(KEY_ALARM_LIST, content);

			System.out.println(content);
		} else {
			editor.putString(KEY_ALARM_LIST, null);
		}
		editor.commit();
	}

	private void readSaveAlarmList() {
		SharedPreferences sp = getContext().getSharedPreferences(
				AlarmView.class.getName(), Context.MODE_PRIVATE);
		String content = sp.getString(KEY_ALARM_LIST, null);

		if (content != null) {
			String[] timeStrings = content.split(",");
			for (String string : timeStrings) {
				adapter.add(new AlarmData(Long.parseLong(string)));
			}
		}
	}

	// 自定义数据类型
	private static class AlarmData {
		private long time = 0;
		private Calendar date;
		private String timeLabel = "";

		public AlarmData(long time) {
			this.time = time;
			date = Calendar.getInstance();
			date.setTimeInMillis(time);
			timeLabel = String.format("%d月%d日   %d:%d",
					date.get(Calendar.MONTH) + 1,
					date.get(Calendar.DAY_OF_MONTH),
					date.get(Calendar.HOUR_OF_DAY), date.get(Calendar.MINUTE));
		}

		public long getTime() {
			return time;
		}

		public String getTimeLabel() {
			return timeLabel;
		}

		public int getId() {
			return (int) (getTime() / 1000 / 60);
		}

		@Override
		public String toString() {
			return getTimeLabel();
		}

	}
}

 

三、计时器

计时器的主要功能就是你先设定一个时间,然后点击开始,时间就会一秒一秒的减少,在这里我么主要用到了Timer这个系统的计时器,这代码中没有上面难懂的地方,有些地方已经给上注释了,所以直接贴代码,可能有些人会不知道Timer怎么用,之后的知识点中都会有提到。

 

package com.example.clock;

import java.util.Timer;
import java.util.TimerTask;

import android.R.integer;
import android.app.AlertDialog;
import android.content.Context;
import android.os.Handler;
import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.AttributeSet;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;

public class TimerView extends LinearLayout {

	public TimerView(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	public TimerView(Context context) {
		super(context);
	}

	@Override
	protected void onFinishInflate() {
		super.onFinishInflate();

		btnStart = (Button) findViewById(R.id.btnStart);
		btnPause = (Button) findViewById(R.id.btnPause);
		btnResume = (Button) findViewById(R.id.btnResume);
		btnReset = (Button) findViewById(R.id.btnReset);

		btnStart.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				startTimer();
				btnStart.setVisibility(View.GONE);
				btnPause.setVisibility(View.VISIBLE);
				btnReset.setVisibility(View.VISIBLE);
			}
		});
		
		btnPause.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				stopTimer();
				btnPause.setVisibility(View.GONE);
				btnResume.setVisibility(View.VISIBLE);
			}
		});
		
		btnResume.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				startTimer();
				btnPause.setVisibility(View.VISIBLE);
				btnResume.setVisibility(View.GONE);
			}
		});
		btnReset.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				stopTimer();
				etHour.setText("00");
				etMin.setText("00");
				etSec.setText("00");
				
				btnReset.setVisibility(View.GONE);
				btnResume.setVisibility(View.GONE);
				btnPause.setVisibility(View.GONE); 
				btnStart.setVisibility(View.VISIBLE); 
			}
		});

		etHour = (EditText) findViewById(R.id.etHour);
		etMin = (EditText) findViewById(R.id.etMin);
		etSec = (EditText) findViewById(R.id.etSec);

		etHour.setText("00");
		etHour.addTextChangedListener(new TextWatcher() {

			@Override
			public void onTextChanged(CharSequence s, int start, int before,
					int count) {
				/*
				 * 这个方法是在Text改变过程中触发调用的, 它的意思就是说在原有的文本s中,
				 * 从start开始的count个字符替换长度为before的旧文本,
				 * 注意这里没有将要之类的字眼,也就是说一句执行了替换动作。
				 */
				if (!TextUtils.isEmpty(s)) {

					int value = Integer.parseInt(s.toString());

					if (value > 59) {
						etHour.setText("59");
					} else if (value < 0) {
						etHour.setText("00");
					}
				}
				checkToEnableBtnStart();
			}

			@Override
			public void beforeTextChanged(CharSequence s, int start, int count,
					int after) {
			}

			@Override
			public void afterTextChanged(Editable s) {
			}
		});
		etMin.setText("00");
		etMin.addTextChangedListener(new TextWatcher() {

			@Override
			public void onTextChanged(CharSequence s, int start, int before,
					int count) {
				if (!TextUtils.isEmpty(s)) {

					int value = Integer.parseInt(s.toString());

					if (value > 59) {
						etMin.setText("59");
					} else if (value < 0) {
						etMin.setText("00");
					}
				}
				checkToEnableBtnStart();
			}

			@Override
			public void beforeTextChanged(CharSequence s, int start, int count,
					int after) {
			}

			@Override
			public void afterTextChanged(Editable s) {
			}
		});
		etSec.setText("00");
		etSec.addTextChangedListener(new TextWatcher() {

			@Override
			public void onTextChanged(CharSequence s, int start, int before,
					int count) {
				if (!TextUtils.isEmpty(s)) {

					int value = Integer.parseInt(s.toString());

					if (value > 59) {
						etSec.setText("59");
					} else if (value < 0) {
						etSec.setText("00");
					}
				}
				checkToEnableBtnStart();
			}

			@Override
			public void beforeTextChanged(CharSequence s, int start, int count,
					int after) {
			}

			@Override
			public void afterTextChanged(Editable s) {
			}
		});

		btnStart.setVisibility(View.VISIBLE);
		btnStart.setEnabled(false);
		btnPause.setVisibility(View.GONE);
		btnResume.setVisibility(View.GONE);
		btnReset.setVisibility(View.GONE);
	}

	private void checkToEnableBtnStart() {
		btnStart.setEnabled((!TextUtils.isEmpty(etHour.getText()) && Integer
				.parseInt(etHour.getText().toString()) > 0)
				|| (!TextUtils.isEmpty(etMin.getText()) && Integer
						.parseInt(etMin.getText().toString()) > 0)
				|| (!TextUtils.isEmpty(etSec.getText()) && Integer
						.parseInt(etSec.getText().toString()) > 0));
	}

	private void startTimer() {
		if (timerTask == null) {
			allTimeCount = Integer.parseInt(etHour.getText().toString()) * 60
					* 60 + Integer.parseInt(etMin.getText().toString()) * 60
					+ Integer.parseInt(etSec.getText().toString());
			timerTask = new TimerTask() {

				@Override
				public void run() {
					allTimeCount--;
					handle.sendEmptyMessage(MSG_WHAT_TIME_TICK);
					if (allTimeCount <= 0) {
						handle.sendEmptyMessage(MSG_WHAT_TIME_IS_UP);
						stopTimer();
					}
				}
			};
			timer.schedule(timerTask, 1000, 1000);
		}
	}
	private void stopTimer(){
		if (timerTask!=null) {
			timerTask.cancel();
			timerTask=null;
		}
	}

	private Handler handle = new Handler(){
		
		public void handleMessage(android.os.Message msg) {
			switch (msg.what) {
			case MSG_WHAT_TIME_TICK:
				int hour = allTimeCount/60/60;
				int min = (allTimeCount/60)%60;
				int sec = allTimeCount%60;
				
				etHour.setText(hour+"");
				etMin.setText(min+"");
				etSec.setText(sec+"");
				break;
				
			case MSG_WHAT_TIME_IS_UP:	
				new AlertDialog.Builder(getContext())
				.setTitle("Time is up!")
				.setMessage("Time is up!")
				.setNegativeButton("Cancle", null).show();
				
				btnReset.setVisibility(View.GONE);
				btnResume.setVisibility(View.GONE);
				btnPause.setVisibility(View.GONE); 
				btnStart.setVisibility(View.VISIBLE); 
				break;

			default:
				break;
			}
		};
	};
	private static final int MSG_WHAT_TIME_IS_UP = 1;
	private static final int MSG_WHAT_TIME_TICK = 2;
	
	private int allTimeCount = 0;
	private Timer timer = new Timer();
	private TimerTask timerTask = null;
	private Button btnStart, btnPause, btnResume, btnReset;
	private EditText etHour, etMin, etSec;

}

 

四、秒表

最后的秒表相信大家都不陌生,用到的知识正好之前的三个都有讲到,只要明白前三个后,这个就不难理解了。

 

package com.example.clock;

import java.util.ArrayList;
import java.util.Timer;
import java.util.TimerTask;

import android.content.Context;
import android.os.Handler;
import android.util.AttributeSet;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;

public class StopWatchView extends LinearLayout {

	private TextView tvHour,tvMin,tvSec,tvMsec;
	private Button btnStart,btnPause,btnResume,btnReset,btnLap;
	private ListView lvTimeList;
	private ArrayAdapter adapter;
	public StopWatchView(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	@Override
	protected void onFinishInflate() {
		super.onFinishInflate();
		
		tvHour = (TextView) findViewById(R.id.timeHour);
		tvHour.setText("0");
		tvMin = (TextView) findViewById(R.id.timeMin);
		tvMin.setText("0");
		tvSec = (TextView) findViewById(R.id.timeSec);
		tvSec.setText("0");
		tvMsec = (TextView) findViewById(R.id.timeMsec);
		tvMsec.setText("0");
		
		btnStart = (Button) findViewById(R.id.btnSWStart);
		btnPause = (Button) findViewById(R.id.btnSWPause);
		btnResume = (Button) findViewById(R.id.btnSWResume);
		btnLap = (Button) findViewById(R.id.btnSWLap);
		btnReset = (Button) findViewById(R.id.btnSWReset);
		
		btnStart.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				startTimer();
				btnStart.setVisibility(View.GONE);
				btnPause.setVisibility(View.VISIBLE);
				btnLap.setVisibility(View.VISIBLE);
			}
		});
		btnPause.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				stopTimer();
				btnPause.setVisibility(View.GONE);
				btnResume.setVisibility(View.VISIBLE);
				btnLap.setVisibility(View.GONE);
				btnReset.setVisibility(View.VISIBLE);
			}
		});
		btnResume.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				startTimer();
				btnResume.setVisibility(View.GONE);
				btnPause.setVisibility(View.VISIBLE);
				btnLap.setVisibility(View.VISIBLE);
				btnReset.setVisibility(View.GONE);
			}
		});
		btnReset.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				stopTimer();
				tenMSecs = 0;
				adapter.clear();
				btnReset.setVisibility(View.GONE);
				btnLap.setVisibility(View.GONE);
				btnPause.setVisibility(View.GONE);
				btnResume.setVisibility(View.GONE);
				btnStart.setVisibility(View.VISIBLE);
			}
		});
		btnLap.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				adapter.insert(String.format("%d:%d:%d.%d", tenMSecs/100/60/60,tenMSecs/100/60%60,tenMSecs/100%60,tenMSecs%100), 0);
			}
		});
		btnLap.setVisibility(View.GONE);
		btnPause.setVisibility(View.GONE);
		btnResume.setVisibility(View.GONE);
		btnReset.setVisibility(View.GONE);
		
		lvTimeList = (ListView) findViewById(R.id.lvWatchTime);
		adapter = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1);
		lvTimeList.setAdapter(adapter);
		
		showTimerTask = new TimerTask() {
			
			@Override
			public void run() {
				handle.sendEmptyMessage(MSG_WHAT_SHOW_TIME);
			}
		};
		timer.schedule(showTimerTask, 200, 200);
	}
	
	private void startTimer(){
		if (timerTask == null) {
			timerTask = new TimerTask() {
				
				@Override
				public void run() {
					tenMSecs++;
				}
			};
			timer.schedule(timerTask, 10, 10);
		}
	}
	private void stopTimer(){
		if (timerTask != null) {
			timerTask.cancel();
			timerTask = null;
		}
	}
	
	private int tenMSecs = 0;
	private Timer timer =new Timer();
	private TimerTask timerTask = null;
	private TimerTask showTimerTask = null;
	private static final int MSG_WHAT_SHOW_TIME = 1;
	
	private Handler handle = new Handler(){
		public void handleMessage(android.os.Message msg) {
			switch (msg.what) {
			case MSG_WHAT_SHOW_TIME:
				tvHour.setText(tenMSecs/100/60/60+"");
				tvMin.setText(tenMSecs/100/60%60+"");
				tvSec.setText(tenMSecs/100%60+"");
				tvMsec.setText(tenMSecs%100+"");
				break;

			default:
				break;
			}
		};
	};
	public void onDestroy() {
		timer.cancel();
	}
	
}

 

 

 

 

到此为止,自己的第一个实战算是完成了,但是就是界面很low,这个只是把基本的功能实现了,但是在界面上没有做很大的完善,在之后的实战中会慢慢改进的。

 

实战完整代码

 

实战知识点

 

 


 

 

 

 

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