安卓实现简单定时器功能源码

package com.fit.timer; import java.util.Date; import java.util.TimerTask; import java.util.Timer; import android.app.Activity; import android.app.AlertDialog; import android.content.DialogInterface; import android.content.Intent; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.util.Log; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; import android.widget.Toast; public class StopwatchActivity extends Activity { /** Called when the activity is first created. */ private Button start_pause, reset; protected static EditText edit; protected static int time_input = 0; protected static boolean flag = false; protected static boolean pauseflag = false; protected static int time_now = 0; protected static TextView timeView; Timer timer= new Timer(); TimerTask task = null; Handler handler=new Handler(){ public void handleMessage(android.os.Message msg) { switch(msg.what) { case 1: { if(time_now == time_input) { flag = false; task.cancel(); // 给用户提示 showDialog(); time_now = 0; pauseflag = false; } else { time_now ++; timeView.setText(String.valueOf(time_now)); } break; } } }; }; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.stopwatch_activity); timeView=(TextView) findViewById(R.id.timeview); start_pause = (Button) findViewById(R.id.start_pause); reset = (Button) findViewById(R.id.reset); edit = (EditText) findViewById(R.id.edit); start_pause.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { if(time_now == 0 && pauseflag == false) { flag = true; time_input = Integer.parseInt(edit.getText().toString()); task=new TimerTask() { @Override public void run() { Message message=new Message(); message.what=1; handler.sendMessage(message); if(time_now == time_input) { System.gc(); } } }; timer.scheduleAtFixedRate(task, new Date(), 1000); } else if(pauseflag) { flag = false; task.cancel(); System.gc(); } else { flag = true; task=new TimerTask() { @Override public void run() { Message message=new Message(); message.what=1; handler.sendMessage(message); if(time_now == time_input) { System.gc(); } } }; timer.scheduleAtFixedRate(task, new Date(), 1000); } pauseflag = !pauseflag; } }); reset.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { if( time_now != 0) { flag = false; task.cancel(); System.gc(); pauseflag = false; } time_now = 0; timeView.setText(String.valueOf(time_now)); } }); } @Override public void onResume() { super.onResume(); if((time_now != 0)&&(time_input != 0)&&(time_input == time_now-1)) { timeView.setText(String.valueOf((StopwatchActivity.time_now-1))); edit.setText(String.valueOf(StopwatchActivity.time_input)); time_now = 0; flag = false; pauseflag = false; showDialog(); stopService(new Intent("com.fit.timer.action.StopwatchService")); } } @Override public void onStop() { super.onStop(); if(flag == true && time_now != 0) { task.cancel(); System.gc(); startService(new Intent("com.fit.timer.action.StopwatchService")); Log.i("我要启动后台服务了","StopwatchService"); } } protected void showDialog() { AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setIcon(R.mipmap.ic_launcher); builder.setTitle("Notification").setMessage("Time is over.") .setPositiveButton("Enter", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { } }); AlertDialog dialog = builder.create(); dialog.show(); } }