0

我显示所有应用程序的主要类在下面，我在其中创建了一个 onclick 侦听器来选择一个应用程序，然后发送以检查它是否存在于数据库中

public class MainActivity extends ListActivity implements OnItemClickListener {

    private ArrayList<String> application_name = new ArrayList<String>();

    List<ResolveInfo> list;

    String[] myapps_name= new String[application_name.size()];
    ResolveInfo rInfo;
    String error;
    String packagename;
    String returnedPackageName;
    public boolean myappisindatabase=false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        PackageManager pm = this.getPackageManager();

        Intent intent = new Intent(Intent.ACTION_MAIN, null);
        intent.addCategory(Intent.CATEGORY_LAUNCHER);

        list = pm.queryIntentActivities(intent, PackageManager.PERMISSION_GRANTED);
        for (ResolveInfo rInfo: list) {
            application_name.add((String) rInfo.activityInfo.applicationInfo.loadLabel(pm));
            Log.w("Installed Applications", rInfo.activityInfo.applicationInfo.loadLabel(pm).toString());
        }

        getListView().setOnItemClickListener(this);
        myapps_name = application_name.toArray(myapps_name);
        setListAdapter(new ArrayAdapter(this, android.R.layout.simple_list_item_1, myapps_name));
    }

    @Override
    public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
        final ActivityInfo info = list.get(arg2).activityInfo;
        packagename = info.packageName;

        checkifindatabase();

        if(!myappisindatabase) {
            AlertDialog.Builder a = new AlertDialog.Builder(MainActivity.this);
            a.setMessage("Do you want to lock this app");
            a.setCancelable(true);
            a.setPositiveButton("Yes, lock my app", new DialogInterface.OnClickListener() {

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    boolean diditwork = true;
                    try {
                        Mylockedapps entry = new Mylockedapps(MainActivity.this);
                        entry.open();
                        entry.createEntry(packagename);
                        entry.close();
                    } catch(Exception e) {
                        diditwork = false;
                        error = e.toString();
                        Intent didntwork= new Intent(MainActivity.this, MainActivity.class);
                        startActivity(didntwork);
                    } finally {
                        if (diditwork) {
                            Intent databaseadd= new Intent(MainActivity.this, DatabaseView.class);
                            startActivity(databaseadd);
                        }
                    }
                }
            });

            AlertDialog alert= a.create();
            a.show();
        }

        if (myappisindatabase) {
            AlertDialog.Builder a= new AlertDialog.Builder(MainActivity.this);
            a.setMessage("Do you want to unlock this app");
            a.setCancelable(true);
            a.setPositiveButton("Yes, unlock my app", new DialogInterface.OnClickListener() {

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    boolean diditdelete= true;
                    try {
                        Mylockedapps entry= new Mylockedapps(MainActivity.this);
                        entry.open();
                        entry.deleteEntry(packagename);
                        entry.close();
                    } catch(Exception e) {
                        diditdelete = false;
                        error = e.toString();
                        Intent didntwork = new Intent(MainActivity.this, MainActivity.class);
                        startActivity(didntwork);
                    } finally {
                        if (diditdelete) {
                            Intent deleted = new Intent(MainActivity.this, Deleted.class);
                            startActivity(deleted);
                        }
                    }
                }
            });

            AlertDialog alert = a.create();
            a.show();
        }
    }

    public boolean checkifindatabase() {
        boolean diditfind = true;
        try {
            Mylockedapps myapp = new Mylockedapps(this);
            myapp.open();
            returnedPackageName = myapp.getPackageName(packagename);
            myapp.close();
        } catch(Exception e) {
            diditfind = false;
            error = e.toString();
            Intent didntwork = new Intent(MainActivity.this, Found.class);
            startActivity(didntwork);
        }

        if(packagename.equals(returnedPackageName))
            myappisindatabase=true;
        else
            myappisindatabase=false;

        return true;
    }
}

我的数据库类是

public class Mylockedapps {
    public static final String KEY_ROWID = "_id";
    public static final String APPS_PACKAGENAME = "apps_packagename";

    private static final String DATABASE_NAME = "MyLockedApps";
    private static final String DATABASE_TABLE = "AppsTable";
    private static final int DATABASE_VERSION = 1;

    private DbHelper ourHelper;
    private final Context ourContext;
    private SQLiteDatabase ourDatabase;

    private static class DbHelper extends SQLiteOpenHelper {

        public DbHelper(Context context) {
            super(context, DATABASE_NAME, null,DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            db.execSQL("CREATE TABLE " + DATABASE_TABLE + "(" +
                        KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                        APPS_PACKAGENAME + " TEXT NOT NULL);");
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion,
                              int newVersion) {
            // TODO Auto-generated method stub
            db.execSQL("DROP TABLE IF EXITS " + DATABASE_TABLE);
            onCreate(db);
        }
    }

    public Mylockedapps(Context c) {
        ourContext = c;
    }

    public Mylockedapps open() throws SQLException {
        ourHelper = new DbHelper(ourContext);
        ourDatabase = ourHelper.getWritableDatabase();
        return this;
    }

    public void close() {
        ourHelper.close();
    }

    public long createEntry(String packagename) {
        ContentValues cv = new ContentValues();
        cv.put(APPS_PACKAGENAME, packagename);
        return ourDatabase.insert(DATABASE_TABLE, null, cv);
    }

    public String getData() {
        String[] columns = new String[]{KEY_ROWID,APPS_PACKAGENAME};
        Cursor c = ourDatabase.query(DATABASE_TABLE, columns, null, null, null, null, null, null);
        String result = "";
        int iRow = c.getColumnIndex(KEY_ROWID);
        int iApps = c.getColumnIndex(APPS_PACKAGENAME);

        for(c.moveToFirst();!c.isAfterLast();c.moveToNext()) {
            result= result + c.getString(iRow) + " " + c.getString(iApps) + "\n";
        }
        return result;
    } 

    public String getPackageName(String findthisapp) throws SQLException {
        String[] columns = new String[]{KEY_ROWID,APPS_PACKAGENAME};
        Cursor c = ourDatabase.query(DATABASE_TABLE, columns, APPS_PACKAGENAME , null, null, null, null, null);

        if (c != null) {
            c.moveToFirst();
            String packagename = c.getString(1);

            if (packagename.equals(findthisapp))
                return packagename;
            else 
                return null;
        }
        return null;
    }

    public void deleteEntry (String packagename)throws SQLException {
        ourDatabase.delete(DATABASE_TABLE, APPS_PACKAGENAME + "=" + packagename, null);
    }
}

我的错误是

close() was never explicitly called on database '/data/data/com.ku.installedapps/databases/MyLockedApps' 
android.database.sqlite.DatabaseObjectNotClosedException: Application did not close the      cursor or database object that was opened here

以及类似的其他错误.....我认为在我发送一个字符串以检查它是否与部分存储在数据库中的任何包名称匹配时出现错误

public String getPackageName(String findthisapp) throws SQLException{
4

2 回答 2

0

您必须以这种方式关闭光标

public String getPackageName(String findthisapp) throws SQLException{
        // TODO Auto-generated method stub
        String[] columns= new String[]{KEY_ROWID,APPS_PACKAGENAME};
        Cursor c= ourDatabase.query(DATABASE_TABLE, columns, APPS_PACKAGENAME , null, null, null, null, null);
        if(c.getCount()!=0){
            c.moveToFirst();
            String packagename= c.getString(1);
            if(packagename.equals(findthisapp)){
                c.close();
                return packagename;
            }else{
                c.close();
                return null;
            }
        }
        c.close();
        return null;
    }
于 2013-07-09T04:33:18.307 回答
0

由于您在这里没有完整的 LogCat，所以我从给定的错误中猜测是您在某个地方调用myapp.open();但没有调用myapp.close();. 我猜测的是，如果您的函数myapp.getPackageName(packagename);返回错误，那么您myapp.close()永远不会被调用，从而导致您看到的错误。只需尝试在 try-catch 块之外调用 open()、close() 即可。

把它放在 OnCreate() 函数中：

Mylockedapps myapp = new Mylockedapps(this);
try{
    myapp.open();

}catch(SQLException e){

}

像这样离开你的 checkifindatabase() 函数：

public boolean checkifindatabase() {
    boolean diditfind = true;

    try {
        returnedPackageName = myapp.getPackageName(packagename);
    } catch(Exception e) {
        diditfind = false;
        error = e.toString();
        Intent didntwork = new Intent(MainActivity.this, Found.class);
        startActivity(didntwork);
    }
    if(packagename.equals(returnedPackageName))
        myappisindatabase=true;
    else
        myappisindatabase=false;

    return true;
}

在您的 onPause() 函数调用中：

myapp.close();

这将确保您始终关闭它。希望这可以帮助。

于 2013-07-09T03:05:50.360 回答