Service实时向Activity传递数据案例
演示一个案例,需求如下:
在Service组件中创建一个线程,该线程用来生产数值,每隔1秒数值自动加1,然后把更新后的数值在界面上实时显示。
步骤如下:
1、新建一个android项目工程,取名为demo。
2、新建一个Service类,用来实时生产数值,供界面实时显示。
package com.ljq.activity; import android.app.Service; import android.content.Intent; import android.os.IBinder; import android.util.Log; public class CountService extends Service { private int count = 0; private boolean threadDisable=false; @Override public void onCreate() { super.onCreate(); new Thread(new Runnable() { @Override public void run() { while (!threadDisable) { try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } count++; Log.v("CountService", "Count is " + count); //发送广播 Intent intent=new Intent(); intent.putExtra("count", count); intent.setAction("com.ljq.activity.CountService"); sendBroadcast(intent); } } }).start(); } @Override public IBinder onBind(Intent intent) { return null; } @Override public void onDestroy() { super.onDestroy(); count=0; threadDisable = true; Log.v("CountService", "on destroy"); } }
3、新建一个Activity类,显示数据。
package com.ljq.activity; import android.app.Activity; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.EditText; public class MainActivity extends Activity { private EditText editText=null; private MyReceiver receiver=null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); editText=(EditText)findViewById(R.id.editText); //启动服务 startService(new Intent(MainActivity.this, CountService.class)); //注册广播接收器 receiver=new MyReceiver(); IntentFilter filter=new IntentFilter(); filter.addAction("com.ljq.activity.CountService"); MainActivity.this.registerReceiver(receiver,filter); } @Override protected void onDestroy() { //结束服务 stopService(new Intent(MainActivity.this, CountService.class)); super.onDestroy(); } /** * 获取广播数据 * * @author jiqinlin * */ public class MyReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { Bundle bundle=intent.getExtras(); int count=bundle.getInt("count"); editText.setText(count+""); } } }
4、main.xml布局文件
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <EditText android:layout_width="fill_parent" android:layout_height="wrap_content" android:cursorVisible="false" android:editable="false" android:id="@+id/editText"/> </LinearLayout>
5、清单文件
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.ljq.activity" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".MainActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <service android:name =".CountService" /> </application> <uses-sdk android:minSdkVersion="7" /> </manifest>
效果如下: