Android应用程序的前景用法

Question

I have an Android app that tracks last time an app used in the foreground. How can I count each time the app is active for an interval of time?

public static void printUsageStats(List<UsageStats> usageStatsList){
    for (UsageStats u : usageStatsList){
        Log.d(TAG, "Pkg: " + u.getPackageName() +  "\t" + "ForegroundTime: "
                + u.getTotalTimeInForeground()) ;
    }

}

Answer 1

log to a file!

getTotalTimeInForeground()

this method returns times and not how MANY so create file onCreate() of main activity and check if file exists and set new value

File f = getApplicationContext().getFileStreamPath("count");
if(!f.exists){
try {
String fileName = ".countFile";
FileOutputStream fOut = context.openFileOutput(fileName, MODE_PRIVATE);//don't use append
fOut.write((/*Count Integer*/).getBytes());
fOut.flush();
fOut.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
else{
//read file and add +1 to existing file
}