Question

我必须为Android开发一个app locker，用户可以阻止应用，而其他用户无法使用访问密钥访问这些应用。

我已安装了应用，但我不知道如何锁定此应用。

请建议我。

Answer 1

这不是堆栈溢出的工作原理。你甚至不用尝试任何东西就无法提出完整的解决方案。

对于最基本的应用版本，您需要执行三项功能。

获取设备上所有已安装应用的列表，并在带有复选框的ListView中显示它们。如果用户检查任何应用程序，请将应用程序添加到其他列表中，例如BlockedAppsList（将是用户想要阻止的应用程序列表）。您可以使用以下代码安装所有应用程序：

final PackageManager pm = getPackageManager();
//get a list of installed apps.
List<ApplicationInfo> packages = pm.getInstalledApplications(PackageManager.GET_META_DATA);

for (ApplicationInfo packageInfo : packages) {
Log.d(TAG, "Installed package :" + packageInfo.packageName);
Log.d(TAG, "Source dir : " + packageInfo.sourceDir);
Log.d(TAG, "Launch Activity :" + pm.getLaunchIntentForPackage(packageInfo.packageName)); 
}

检查当前打开的应用是哪个。您可以使用以下代码进行检查：

ActivityManager am = (ActivityManager) this.getSystemService(ACTIVITY_SERVICE);
List l = am.getRecentTasks(1, ActivityManager.RECENT_WITH_EXCLUDED);
Iterator i = l.iterator();
PackageManager pm = this.getPackageManager();
while (i.hasNext()) {
ActivityManager.RunningAppProcessInfo info = (ActivityManager.RunningAppProcessInfo)(i.next());
try {
CharSequence c = pm.getApplicationLabel(pm.getApplicationInfo(
info.processName, PackageManager.GET_META_DATA));
Log.w("LABEL", c.toString());
} catch (Exception e) {
// Name Not FOund Exception
    }
   }

现在检查当前应用是否存在于BlockedAppsList中，如果它存在，您可以显示任何带有阻止消息的屏幕。

Answer 2

假设您将锁定的应用程序的程序包名称存储在名为：

的表中

锁

，您想调用一个名为

的活动

PasswordActivity

每当用户启动锁定的应用程序时，您可以实施如下所示的轮询机制：

public class CheckAppLaunchThread extends Thread {

private Context context;
private Handler handler;
private ActivityManager actMan;
private int timer = 100;
public static final String TAG = "App Thread";
public static String lastUnlocked;

// private String lastUnlocked;

public CheckAppLaunchThread(Handler mainHandler, Context context) {
    this.context = context;
    this.handler = mainHandler;
    actMan = (ActivityManager) context
            .getSystemService(Context.ACTIVITY_SERVICE);
    this.setPriority(MAX_PRIORITY);
}

@Override
public void run() {
    context.startService(new Intent(context, AppLockService.class));
    Looper.prepare();
    String prevTasks;
    String recentTasks = "";

    prevTasks = recentTasks;
    Log.d("Thread", "Inside Thread");
    while (true) {
        try {
            String topPackageName = "";
            if(Build.VERSION.SDK_INT >= 21) {
                UsageStatsManager mUsageStatsManager = (UsageStatsManager) context.getSystemService("usagestats");                       
                long time = System.currentTimeMillis(); 
                // We get usage stats for the last 10 seconds
                List<UsageStats> stats = mUsageStatsManager.queryUsageStats(UsageStatsManager.INTERVAL_DAILY, time - 1000*5, time);                                    
                if(stats != null) {
                    SortedMap<Long,UsageStats> mySortedMap = new TreeMap<Long,UsageStats>();
                    for (UsageStats usageStats : stats) {
                        mySortedMap.put(usageStats.getLastTimeUsed(),usageStats);
                    }                    
                    if(mySortedMap != null && !mySortedMap.isEmpty()) {
                        topPackageName =  mySortedMap.get(mySortedMap.lastKey()).getPackageName();                                   
                    }                                       
                }
            }
            else {
                topPackageName = actMan.getRunningAppProcesses().get(0).processName;
            }
            recentTasks = topPackageName;
            Thread.sleep(timer);
            if (recentTasks.length()==0 || recentTasks.equals(
                    prevTasks)) {
            } else {
                if (isAppLocked(recentTasks)) {
                    Log.d(TAG, "Locked " + recentTasks);
                    handler.post(new RequestPassword(context, recentTasks));
                }
            }

        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        prevTasks = recentTasks;

    }

}

class ToastRunnable implements Runnable {

    String message;

    public ToastRunnable(String text) {
        message = text;
    }

    @Override
    public void run() {
        Toast.makeText(context, message, Toast.LENGTH_SHORT).show();

    }
}

class RequestPassword implements Runnable {

    private Context mContext;
    private String pkgName;

    public RequestPassword(Context mContext, String pkgName) {
        this.mContext = mContext;
        this.pkgName = pkgName;
    }

    @Override
    public void run() {

        Intent passwordAct = new Intent(context, PasswordActivity.class);
        passwordAct.putExtra("PACKAGE_NAME", pkgName);
        passwordAct.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_SINGLE_TOP);
        this.mContext.startActivity(passwordAct);

    }

}

private boolean isAppLocked(String packageName) {
    if (packageName.equals(PasswordActivity.lastUnlocked)) {
        return false;
    }
    PasswordActivity.lastUnlocked = null;
    DatabaseHelper dbHelper = new DatabaseHelper(context);
    SQLiteDatabase db = dbHelper.getReadableDatabase();
    Cursor cursor = db.rawQuery("SELECT * FROM locks WHERE package_name=\'"
            + packageName + "\'", null);
    boolean isLocked = false;
    if (cursor.moveToNext()) {
        isLocked = true;
    }

    cursor.close();
    db.close();
    dbHelper.close();
    return isLocked;
}

}

现在，您必须像这样从服务中调用上述代码：

@Override
public void onCreate() {
    handler = new Handler(getMainLooper());
    context = getApplicationContext();
    launchChecker = new CheckAppLaunchThread(handler, context);
    super.onCreate();
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    while (true) {
        if (!launchChecker.isAlive())
            launchChecker.start();
        return START_STICKY;

    }
}

警告：自 Oreo 以来，Google一直限制后台服务，因此您必须找出一种使服务始终有效的方法。（这不是此问题的范围）的线索，请考虑安排一个JobService和一个广播接收器，以便在Android杀死它时重新安排您的服务。

如何在Android中制作应用程序锁定应用程序？

2 个答案: