我正在处理一个项目，该项目需要每2分钟检查一次数据库中的标记状态，但我的广播接收器类没有触发。
Mainactivity
public class MainActivity extends Activity {
Button b1;
PendingIntent pendingIntent;
AlarmManager alarmManager;
int year,month,day,hour,min;
@SuppressWarnings("static-access")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
mystart();
}
});
Intent i = new Intent(this,myBackgroundChecker.class);
pendingIntent.getBroadcast(this, 0, i, 0);
alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void mystart(){
Calendar c = Calendar.getInstance();
year = c.get(Calendar.YEAR);
month = c.get(Calendar.MONTH);
day = c.get(Calendar.DAY_OF_MONTH);
hour = c.get(Calendar.HOUR_OF_DAY);
min = c.get(Calendar.MINUTE);
month+=1;
min+=1;
Toast.makeText(getBaseContext(), ""+hour+min+" day: "+day+ "month :"+month+"Year : "+year, Toast.LENGTH_LONG).show();
c.set(Calendar.DAY_OF_MONTH,day);
c.set(Calendar.MONTH, month);
c.set(Calendar.YEAR, year);
c.set(Calendar.HOUR_OF_DAY, hour);
c.set(Calendar.MINUTE,min+1);
int repeat = 1000*60*2;
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, c.getTimeInMillis(), repeat, pendingIntent);
}
}
myBackgroundChecker.java
public class myBackgroundChecker extends BroadcastReceiver{
static MediaPlayer mp;
InputStream is=null;
String result="";
ArrayList<NameValuePair> nameValuePairs;
@Override
public void onReceive(Context arg0, Intent arg1) {
// TODO Auto-generated method stub
mp = MediaPlayer.create(arg0, R.raw.alert);
mp.setLooping(true);
//myDb m = new myDb();
nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("flag","0"));
Toast.makeText(arg0, "service started", Toast.LENGTH_SHORT).show();
//m.execute();
//First reading if 1 or not!
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://192.168.0.102/get.php");
//httppost.setEntity((HttpEntity) new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection "+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
Log.e("myTag", result);
// Toast.makeText(getBaseContext(), result, Toast.LENGTH_SHORT).show();
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
if(result.equals("1")){
mp.start();
}
// after trigering alarm setting to 0
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://192.168.0.102/set.php");
httppost.setEntity((HttpEntity) new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection "+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
Log.e("myTag", result);
// Toast.makeText(getBaseContext(), result, Toast.LENGTH_SHORT).show();
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
}
清单
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.remotealarm_client"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.remotealarm_client.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>
<receiver android:name="com.example.remotealarm_client.myBackgroundChecker">
<intent-filter >
<action android:name="android.intent.action.BOOT_COMPLETED">
</action>
</intent-filter>
</receiver>
</application>
</manifest>
答案 0 :(得分：0)
您发布的代码中有一些问题需要纠正。首先，要为BroadcastReceiver广告发送BOOT_COMPLETED，您需要添加RECEIVE_BOOT_COMPLETED权限。另请注意，自3.1以来，您的应用必须在安装后至少启动一次，才能使其退出已停止状态，以便进行广播。
其次，在确定该警报的初始时间时，您还需要一个月的时间。确实，Calendar的月份是从零开始的，但是您使用的是Calendar的从零开始的值，因此添加一个将其推向下个月。
最后，PendingIntent.getBroadcast()方法是static方法，返回请求的PendingIntent。它没有初始化它被调用的实例（顺便说一句，在这种情况下会导致NullPointerException，如果确实如此）。这意味着您已将空PendingIntent传递给AlarmManager，因此显然不会做任何事情。更改该行以调用类上的方法，并将返回值分配给您的字段。
pendingIntent = PendingIntent.getBroadcast(this, 0, i, 0);