System - Kill Process

//On Button Show Running

populateTextViewWithRunningProcesses();

//On Button Kill
new KillBackgroundProcessesTask().execute();

// Custom method to populate TextView with running processes
protected void populateTextViewWithRunningProcesses(){
     textview1.setText("");
     ActivityManager am = (ActivityManager) getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
     List<ActivityManager.RunningAppProcessInfo> runningProcesses = am.getRunningAppProcesses();
     Toast.makeText(getApplicationContext(),"Running processes : " +
            runningProcesses.size(),Toast.LENGTH_SHORT).show();
     for(ActivityManager.RunningAppProcessInfo processInfo: runningProcesses ){
          textview1.setText(textview1.getText() + processInfo.processName + "
");
     }
}
// AsyncTask to kill background processes
private class KillBackgroundProcessesTask extends AsyncTask<Void,Integer,Integer>{
   @Override
    protected Integer doInBackground(Void...Void){
            android.content.pm.PackageManager pm = getPackageManager();
            ActivityManager am = (ActivityManager) getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
            List<ActivityManager.RunningAppProcessInfo> list = am.getRunningAppProcesses();
            int initialRunningProcessesSize = list.size();
            for(ActivityManager.RunningAppProcessInfo process: list){
                if(process.pkgList.length == 0) continue;
                try{
                    android.content.pm.PackageInfo packageInfo = pm.getPackageInfo(process.pkgList[0],android.content.pm.PackageManager.GET_ACTIVITIES);
                    if(!packageInfo.packageName.equals(getApplicationContext().getPackageName())){
                        am.killBackgroundProcesses(packageInfo.packageName);
                    }
                }catch(android.content.pm.PackageManager.NameNotFoundException e){
                    e.printStackTrace();
                }
            }
            int currentRunningProcessesSize = am.getRunningAppProcesses().size();
            return initialRunningProcessesSize - currentRunningProcessesSize;
        }
     protected void onPostExecute(Integer result){
            Toast.makeText(getApplicationContext(),"Killed : " + result + " processes",Toast.LENGTH_SHORT).show();
            populateTextViewWithRunningProcesses();
     }
}

AndroidManifest.xml [permission]

<uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES"/>