这个问题之前已被多次询问，而且他们中的任何一个人都没有一个问题解决了这个问题。我已经尝试了通过按下按钮，进入onPause和onDestroy来取消注册我的监听器的所有方法。但即使应用程序关闭，听众仍然存在。更重要的是，我正在敬酒我的听众正在填充的数组大小，即使应用程序关闭，Toast仍然存在并继续增加。我尝试过使用null和LISTEN_NONE以及我在网上找到的所有其他内容。
// Name of this file is Second.class
public class Second extends Activity {
SignalStrengthListener signalStrengthListener;
TextView lteRsrp;
TextView lteRsrq;
TextView cellPciTextView;
TextView timerValue;
Button startButton, stopButton;
TelephonyManager tm;
List<CellInfo> cellInfoList;
String lte1, lte2;
int cellPci = 0;
long startTime = 0L;
long timeInMilliseconds = 0L;
long timeSwapBuff = 0L;
long updatedTime = 0L;
ArrayList<String> rsrpArray;
ArrayList<String> rsrqArray;
ArrayList<String> pciArray;
Handler customHandler = new Handler();
boolean flag = true;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second_activity);
flag = false;
rsrpArray = new ArrayList<>();
rsrqArray = new ArrayList<>();
pciArray = new ArrayList<>();
lteRsrp = (TextView) findViewById(R.id.lteRsrp);
lteRsrq = (TextView) findViewById(R.id.lteRsrq);
cellPciTextView = (TextView) findViewById(R.id.cellPciTextView);
timerValue = (TextView) findViewById(R.id.timerValue);
startButton = (Button) findViewById(R.id.startButton);
stopButton = (Button) findViewById(R.id.stopButton);
startButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startTime = SystemClock.uptimeMillis();
customHandler.postDelayed(updateTimerThread, 0);
//start the signal strength listener
signalStrengthListener = new SignalStrengthListener();
((TelephonyManager) getSystemService(TELEPHONY_SERVICE)).listen(signalStrengthListener, SignalStrengthListener.LISTEN_SIGNAL_STRENGTHS);
tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
try {
cellInfoList = tm.getAllCellInfo();
} catch (Exception e) {
Log.d("SignalStrength", "+++++++++++++++++++++++++++++++++++++++++ null array spot 1: " + e);
}
try {
for (CellInfo cellInfo : cellInfoList) {
if (cellInfo instanceof CellInfoLte) {
// cast to CellInfoLte and call all the CellInfoLte methods you need
// Gets the LTE PCI: (returns Physical Cell Id 0..503, Integer.MAX_VALUE if unknown)
cellPci = ((CellInfoLte) cellInfo).getCellIdentity().getPci();
}
}
} catch (Exception e) {
Log.d("SignalStrength", "++++++++++++++++++++++ null array spot 2: " + e);
}
}
});
stopButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
timeSwapBuff += timeInMilliseconds;
customHandler.removeCallbacks(updateTimerThread);
flag = true;
try{
if(signalStrengthListener != null) {
tm.listen(signalStrengthListener, SignalStrengthListener.LISTEN_NONE);
Log.d("TAG", "+++++++++++++++++++++++++++++++++++ Success!!!!!!");
}
}catch(Exception e){
e.printStackTrace();
Log.d("TAG", "+++++++++++++++++++++++++++++++++++ Fail!!!!!! with error = " + e);
}
}
});
}
private Runnable updateTimerThread = new Runnable() {
public void run() {
timeInMilliseconds = SystemClock.uptimeMillis() - startTime;
updatedTime = timeSwapBuff + timeInMilliseconds;
int secs = (int) (updatedTime / 1000);
int mins = secs / 60;
secs = secs % 60;
int milliseconds = (int) (updatedTime % 1000);
timerValue.setText("" + mins + ":"
+ String.format("%02d", secs) + ":"
+ String.format("%03d", milliseconds));
customHandler.postDelayed(this, 0);
}
};
private class SignalStrengthListener extends PhoneStateListener {
@Override
public void onSignalStrengthsChanged(android.telephony.SignalStrength signalStrength) {
//++++++++++++++++++++++++++++++++++
((TelephonyManager) getSystemService(TELEPHONY_SERVICE)).listen(signalStrengthListener, SignalStrengthListener.LISTEN_SIGNAL_STRENGTHS);
tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
String ltestr = signalStrength.toString();
String[] parts = ltestr.split(" ");
lte1 = parts[9];
lte2 = parts[10];
try {
cellInfoList = tm.getAllCellInfo();
for (CellInfo cellInfo : cellInfoList) {
if (cellInfo instanceof CellInfoLte) {
// cast to CellInfoLte and call all the CellInfoLte methods you need
// Gets the LTE PCI: (returns Physical Cell Id 0..503, Integer.MAX_VALUE if unknown)
cellPci = ((CellInfoLte) cellInfo).getCellIdentity().getPci();
}
}
} catch (Exception e) {
Log.d("SignalStrength", "+++++++++++++++++++++++++++++++ null array spot 3: " + e);
}
if (!flag) {
rsrpArray.add(lte1);
rsrqArray.add(lte2);
pciArray.add(Integer.toString(cellPci));
int size = rsrpArray.size();
Toast.makeText(Second.this, "Array size = " + size, Toast.LENGTH_LONG).show();
}
lteRsrp.setText(String.valueOf(lte1));
lteRsrq.setText(String.valueOf(lte2));
cellPciTextView.setText(String.valueOf(cellPci));
super.onSignalStrengthsChanged(signalStrength);
//++++++++++++++++++++++++++++++++++++
}
}
@Override
public void onPause() {
Log.d("onPause SigStr", "+++++++++++++++++++++++++++++++++++ onPause");
try{
if(signalStrengthListener != null){
tm.listen(signalStrengthListener, SignalStrengthListener.LISTEN_NONE);
Log.d("TAG", "+++++++++++++++++++++++++++++++++++ Success!!!!!!");
}
}catch(Exception e){
e.printStackTrace();
Log.d("TAG", "+++++++++++++++++++++++++++++++++++ Fail!!!!!! with error = " + e);
}
flag = true;
super.onPause();
}
@Override
public void onDestroy() {
Log.d("onPause SigStr", "+++++++++++++++++++++++++++++++++++ onDestroy");
try{
if(signalStrengthListener != null) {
tm.listen(signalStrengthListener, SignalStrengthListener.LISTEN_NONE);
Log.d("TAG", "+++++++++++++++++++++++++++++++++++ Success!!!!!!");
}
}catch(Exception e){
e.printStackTrace();
Log.d("TAG", "+++++++++++++++++++++++++++++++++++ Fail!!!!!! with error = " + e);
}
flag = true;
super.onDestroy();
}
}
我的代码开始变得丑陋和多余，因为我一直在重新安排事情，希望它可以取消注册我的听众。以下是Second.class的XML布局。 XML布局文件的名称是second_activity.xml：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#42abc0">
<TextView
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text=""
android:textSize="16sp"
android:textColor="#000000"
android:id="@+id/lteRsrp"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true"
android:layout_marginStart="29dp"
android:layout_marginTop="31dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="= LTE RSRP"
android:textSize="16sp"
android:textColor="#000000"
android:id="@+id/textView2"
android:layout_alignTop="@+id/lteRsrp"
android:layout_centerHorizontal="true" />
<TextView
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text=""
android:textColor="#000000"
android:textSize="16sp"
android:id="@+id/lteRsrq"
android:layout_below="@+id/lteRsrp"
android:layout_alignStart="@+id/lteRsrp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="= LTE RSRQ"
android:textSize="16sp"
android:textColor="#000000"
android:id="@+id/textView3"
android:layout_below="@+id/textView2"
android:layout_alignStart="@+id/textView2" />
<TextView
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text=""
android:textSize="16sp"
android:textColor="#000000"
android:id="@+id/cellPciTextView"
android:layout_below="@+id/lteRsrq"
android:layout_alignStart="@+id/lteRsrq" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="= LTE PCI"
android:textSize="16sp"
android:textColor="#000000"
android:id="@+id/textView4"
android:layout_below="@+id/textView3"
android:layout_alignStart="@+id/textView3" />
<Button
android:layout_width="120dp"
android:layout_height="wrap_content"
android:text="Start"
android:textColor="#000000"
android:textSize="22sp"
android:id="@+id/startButton"
android:layout_alignParentBottom="true"
android:layout_toEndOf="@+id/textView3"
android:layout_marginBottom="48dp"
android:background="#ffffff"
android:textAlignment="center"
android:textStyle="bold"
android:padding="4dp" />
<Button
android:layout_width="120dp"
android:layout_height="wrap_content"
android:text="Stop"
android:textSize="22sp"
android:textColor="#000000"
android:id="@+id/stopButton"
android:layout_alignBottom="@+id/startButton"
android:layout_alignStart="@+id/cellPciTextView"
android:background="#ffffff"
android:textStyle="bold"
android:padding="4dp"
android:textAlignment="center" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/timerVal"
android:textSize="40sp"
android:textColor="#000000"
android:id="@+id/timerValue"
android:layout_above="@+id/startButton"
android:layout_centerHorizontal="true"
android:layout_marginBottom="55dp" />
</RelativeLayout>
以下是我的AndroidManifest.xml：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.parksjg.its.pscrindoortesttool" >
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme" >
<activity android:name=".First"
android:screenOrientation="portrait" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".Second"
android:screenOrientation="portrait">
</activity>
</application>
</manifest>
同样，之前已经问过这个问题但是没有一个发布的答案有效!!!这里有一些，并注意到没有一个答案被投票或从未被标记为有效： Android : why PhoneCallListener still alive after activity finish?
Android : how to stop listening a PhoneCallListener?
希望我忽略了一些人可以指出的简单。如果您需要更多代码或希望我在GitHub上发布整个Android Studio项目，请告诉我。
谢谢!!!
答案 0 :(得分：0)
我想我弄清楚发生了什么。我在代码中添加了一些Log.d（）语句来确定SignalStrengthListener被调用了多少次。我运行应用程序3秒钟，发现SignalStrengthListener被调用了大约300次！比我想象的要多得多。现在的问题是，Toast无法跟上它被调用的次数;所以当我停止或关闭应用程序时，Toasts会在几分钟后继续出现。在卸载应用程序之前，我的错误是没有足够的时间让Toasts赶上来，当时我认为这是阻止听众的唯一方法。
为了测试这个，我再次运行应用程序3秒钟，并对SignalStrengthListener进行了273次调用，并且每次调用它都会进行Toast。我停下来关闭了应用程序，Toasts继续出现几分钟。然而，他们终于在273 Toast停了下来。
长话短说，Toast不适合一秒钟多次调用。这是我不理解我的听众如何运作的错。最后，我设置的布尔值和我的监听器的LISTEN_NONE标签成功取消注册了监听器。