java - android SQLite，无法再在我的 listView 中查看数据

Question

昨天我创建了一个很好的 listView 来查看我的数据库，但今天我试图将在线添加到我的数据库中，但我收到一条错误消息，内容类似于“数据库泄露。blabla 关闭你的数据库”。之后，我无法再向我的数据库中添加任何行。

但是我重新启动了 android studio 并且我可以添加新行(并且不再有错误)!但是我看不到我添加的新闻行。我只看到我在错误之前添加的行(或者我可以看到我添加的导致错误的行)。我用 chrome 检查了我的数据库，我看到了一切，所以我真的添加了新闻行!

我不知道发生了什么事，我检查了几个类(class)的历史记录，但我没有做出任何不好的改变(我认为)。我怎样才能再次看到我所有的数据库？我还使用 ContentProvider 访问我的数据库。

这是我的带有 ListView 的 Fragment 类(我在 ListView 和一些 TextView 的元素中使用了 2 个按钮):

public class ViewCardEditor extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> {
    public static final String authority = "com.example.jean.cartememoire.CardContentProvider";
    public String[] from;
    public final int[] to = {R.id.idList, R.id.themeList, R.id.questionList, R.id.reponseList, R.id.difficultList};
    StockCard stock;
    ViewGroup container;
    ListView listView;
    MySimpleCursorAdapter adapter;
    private ArrayList<String> data = new ArrayList<String>();



    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup c,
                             Bundle savedInstanceState) {
        container = c;
        View view = inflater.inflate(R.layout.fragment_view_card_editor, container, false);
        stock = StockCard.getInstance(container.getContext());
        from = new String[]{stock._ID,
                stock.THEME,
                stock.QUESTION,
                stock.REPONSE,
                stock.DIFFICULTE};

        // Inflate the layout for this fragment
        if (container != null) {
            container.removeAllViews();
        }
        databaseView(view);

        return view;
    }

    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        Uri.Builder builder = new Uri.Builder();
        Uri uri = builder.scheme("content").authority(authority)
                .appendPath(stock.STOCK_TABLE).build();
        return new CursorLoader(container.getContext(), uri, from,
                null, null, null);
    }
    public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
        adapter.swapCursor(data);
    }
    public void onLoaderReset(Loader<Cursor> loader) {
        adapter.swapCursor(null);
    }



    public void databaseView(View view)
    {
        ArrayList<String> list;
        Cursor cursor = stock.getData();

        listView = (ListView) view.findViewById(R.id.listView);

        adapter = new MySimpleCursorAdapter(container.getContext(), R.layout.card_stock, null, from, to,0);
        listView.setAdapter(adapter);

        LoaderManager manager = getLoaderManager();
        manager.initLoader(0, null, this);

    }


    public void deleteOneCard(int id)
    {
        Uri.Builder builder = new Uri.Builder();
        builder.scheme("content").authority(authority).appendPath(stock.STOCK_TABLE);

        ContentUris.appendId(builder, id);
        Uri uri = builder.build();
        ContentResolver resolver = container.getContext().getContentResolver();
        resolver.delete(uri, null, null);

    }

    private class MySimpleCursorAdapter extends SimpleCursorAdapter
    {
        ViewHolder vh;
        public MySimpleCursorAdapter(Context context, int layout, Cursor c, String[] from, int[] to, int flags) {
            super(context, layout, c, from, to, flags);

        }

        public View newView(Context _context, Cursor _cursor, ViewGroup parent) {
            LayoutInflater inflater = (LayoutInflater) _context.getSystemService(_context.LAYOUT_INFLATER_SERVICE);
            View view = inflater.inflate(R.layout.card_stock, parent, false);
            vh = new ViewHolder();
            vh.idList = (TextView) view.findViewById(R.id.idList);
            vh.themeList = (TextView) view.findViewById(R.id.themeList);
            vh.questionList = (TextView) view.findViewById(R.id.questionList);
            vh.reponseList = (TextView) view.findViewById(R.id.reponseList);
            vh.difficulteList = (TextView) view.findViewById(R.id.difficultList);
            vh.Supprimer = (Button) view.findViewById(R.id.buttonDelete);
            vh.Modifier = (Button) view.findViewById(R.id.buttonModifier);


            view.setTag(vh);
            return view;
        }

        public void bindView(View view, Context Context, Cursor cursor) {
            vh.idList.setText(cursor.getString(cursor.getColumnIndex(stock._ID)));
            vh.themeList.setText(cursor.getString(cursor.getColumnIndex(stock.THEME)));
            vh.questionList.setText(cursor.getString(cursor.getColumnIndex(stock.QUESTION)));
            vh.reponseList.setText(cursor.getString(cursor.getColumnIndex(stock.REPONSE)));
            vh.difficulteList.setText(cursor.getString(cursor.getColumnIndex(stock.DIFFICULTE)));

            vh.Supprimer.setOnClickListener(new View.OnClickListener()
            {
                public void onClick(View v) {
                    View parentView = (View)v.getParent();
                    TextView idList = (TextView) parentView.findViewById(R.id.idList);
                    /*TextView themeList = (TextView) parentView.findViewById(R.id.themeList);
                    TextView questionList = (TextView) parentView.findViewById(R.id.questionList);
                    TextView reponseList = (TextView) parentView.findViewById(R.id.reponseList);
                    TextView difficulteList = (TextView) parentView.findViewById(R.id.difficultList);*/

                    int id = Integer.parseInt(idList.getText().toString());
                    deleteOneCard(id);
                    Toast.makeText(container.getContext(), "Suppression de "+id, Toast.LENGTH_SHORT).show();
                }
            });

            vh.Modifier.setOnClickListener(new View.OnClickListener()
            {
                public void onClick(View v) {
                    View parentView = (View)v.getParent();
                    TextView idList = (TextView) parentView.findViewById(R.id.idList);
                    TextView themeList = (TextView) parentView.findViewById(R.id.themeList);
                    themeList.setFocusable(true);
                    themeList.requestFocus();
                    /*TextView questionList = (TextView) parentView.findViewById(R.id.questionList);
                    TextView reponseList = (TextView) parentView.findViewById(R.id.reponseList);
                    TextView difficulteList = (TextView) parentView.findViewById(R.id.difficultList);*/

                    int id = Integer.parseInt(idList.getText().toString());
                    Toast.makeText(container.getContext(), "bouton Modifier pour "+id, Toast.LENGTH_SHORT).show();
                }
            });

        }
    }



    public class ViewHolder
    {
        Button Supprimer, Modifier;
        TextView idList, themeList, questionList, reponseList, difficulteList;

    }
}

这是我添加新闻行的类(class):

public class AddCardEditor extends Fragment {
    EditText editTheme, editQuest, editRep;
    RatingBar ratingBar;
    Button buttonCreateCard;
    CardContentProvider stock;
    ViewGroup container;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup c,
                             Bundle savedInstanceState) {
        View view;
        view = inflater.inflate(R.layout.fragment_add_card_editor, container, false);
        // Inflate the layout for this fragment
        container = c;
        if (container != null) {
            container.removeAllViews();
        }
        editTheme =(EditText) view.findViewById(R.id.editTheme);
        editQuest =(EditText) view.findViewById(R.id.editQuest);
        editRep =(EditText) view.findViewById(R.id.editRep);
        ratingBar =(RatingBar) view.findViewById(R.id.ratingBar);
        buttonCreateCard =(Button) view.findViewById(R.id.buttonCreateCard);
        stock = new CardContentProvider();
        addData(container);
        return view;
    }

    public void addData(final ViewGroup container)
    {

            buttonCreateCard.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    try
                    {
                        ContentValues cv = new ContentValues();
                        CardContentProvider cp = new CardContentProvider();
                        cv.put(stock.THEME, editTheme.getText().toString());
                        cv.put(stock.QUESTION, editQuest.getText().toString());
                        cv.put(stock.REPONSE, editRep.getText().toString());
                        cv.put(stock.DIFFICULTE, ratingBar.getRating());

                        ContentResolver resolver = container.getContext().getContentResolver();
                        Uri.Builder builder = new Uri.Builder();
                        System.out.println("addDATA DEBUG");
                        builder.scheme("content").authority(stock.authority).appendPath(stock.STOCK_TABLE);
                        System.out.println("addDATA DEBUG2");
                        Uri uri = builder.build();
                        uri = resolver.insert(uri,cv);
                        long id = ContentUris.parseId(uri);
                        System.out.println("addDATA DEBUG3 : "+id);
                        Toast.makeText(container.getContext(), "Carte créé avec succès !", Toast.LENGTH_SHORT).show();
                    }
                    catch (Exception e)
                    {
                        Toast.makeText(container.getContext(), "Erreur, echec de création de la carte", Toast.LENGTH_SHORT).show();
                    }


                }
            });

    }


}

然后是我的 listView 布局:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/relativeList"
    android:descendantFocusability="blocksDescendants">

    <TextView
        android:text="@string/difficult"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView8"
        android:layout_below="@+id/textView7"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_marginTop="29dp" />

    <TextView
        android:text="@string/r_ponse"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView7"
        android:layout_marginTop="20dp"
        android:layout_below="@+id/textView6"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/idList"
        android:layout_alignParentTop="true"
        android:layout_alignLeft="@+id/themeList"
        android:layout_alignStart="@+id/themeList"
        tools:ignore="HardcodedText" />

    <TextView
        android:text="Question :"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView6"
        android:layout_marginTop="14dp"
        android:layout_below="@+id/textView4"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        tools:ignore="HardcodedText" />

    <TextView
        android:text="@string/id"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView3"
        android:layout_alignParentTop="true"
        android:layout_alignRight="@+id/textView4"
        android:layout_alignEnd="@+id/textView4" />

    <TextView
        android:text="Thème :"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView4"
        android:layout_below="@+id/textView3"
        android:layout_alignRight="@+id/textView6"
        android:layout_alignEnd="@+id/textView6"
        tools:ignore="HardcodedText" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/textView6"
        android:id="@+id/questionList"
        android:layout_toRightOf="@+id/themeList"
        android:layout_toEndOf="@+id/themeList" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/textView8"
        android:layout_alignLeft="@+id/questionList"
        android:layout_alignStart="@+id/questionList"
        android:id="@+id/reponseList" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/textView8"
        android:layout_alignRight="@+id/reponseList"
        android:layout_alignEnd="@+id/reponseList"
        android:id="@+id/difficultList"
        android:layout_toEndOf="@+id/reponseList"
        android:layout_toRightOf="@+id/reponseList" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/themeList"
        android:layout_marginLeft="33dp"
        android:layout_marginStart="33dp"
        tools:ignore="HardcodedText"
        android:layout_below="@+id/idList"
        android:layout_toRightOf="@+id/textView8"
        android:layout_toEndOf="@+id/textView8" />

    <Button
        android:text="@string/supprimerb"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:id="@+id/buttonDelete"/>

    <Button
        android:text="@string/modifierB"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/buttonModifier"
        android:layout_alignTop="@+id/questionList"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_alignLeft="@+id/buttonDelete"
        android:layout_alignStart="@+id/buttonDelete" />
</RelativeLayout>

还有我的 ContentProvider 类:

public class CardContentProvider extends ContentProvider {
    private StockCard stock;

    public static String authority = "com.example.jean.cartememoire.CardContentProvider";
    private static String path ="Cartes_table";

    public static final String _ID = "_id";
    public static final String THEME = "THEME";
    public static final String QUESTION = "QUESTION";
    public static final String REPONSE = "REPONSE";
    public static final String DIFFICULTE = "DIFFICULTE"; //# = un chiffre
    public static final String STOCK_TABLE = "Cartes_table";

    private static final int ID_STOCK_TABLE = 1;
    private static final int ID_THEME = 2;
    private static final int ID_QUESTION = 3;
    private static final int ID_REPONSE = 4;
    private static final int ID_DIFFICULTE = 5;
    private static final UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);

    static {
        matcher.addURI(authority, STOCK_TABLE, ID_STOCK_TABLE);
        matcher.addURI(authority, STOCK_TABLE+"/*", ID_STOCK_TABLE);

    }


    @Override
    public boolean onCreate() {
        stock = StockCard.getInstance(getContext());
        return true;
    }

    @Nullable
    @Override
    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
        SQLiteDatabase db = stock.getReadableDatabase();
        int code = matcher.match(uri);
        long id;
        Cursor cursor;

        switch (code)
        {
            case ID_STOCK_TABLE:
                cursor = db.query(STOCK_TABLE, projection, selection,
                        selectionArgs, null, null, sortOrder);
                break;
            default:
                Log.d("Uri provider =", uri.toString());
                throw new UnsupportedOperationException("Pas encore implémenté");
        }

        return cursor;
    }

    @Nullable
    @Override
    public String getType(Uri uri) {
        return null;
    }

    @Nullable
    @Override
    public Uri insert(Uri uri, ContentValues values) {
        SQLiteDatabase db = stock.getWritableDatabase();
        int code = matcher.match(uri);
        long id;
        Uri.Builder builder = new Uri.Builder();

        switch(code)
        {
            case ID_STOCK_TABLE:
                System.out.println(values.toString());
                id = db.insert(STOCK_TABLE, null, values);
                builder.appendPath(STOCK_TABLE);
                break;
            default:
                throw new UnsupportedOperationException("Pas encore implémenté");
        }

        builder.authority(authority);
        builder = ContentUris.appendId(builder, id);

        return builder.build();
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        SQLiteDatabase db = stock.getWritableDatabase();
        int code = matcher.match(uri);
        int i;

        switch(code)
        {
            case ID_STOCK_TABLE:
                long id = ContentUris.parseId(uri);
                i = db.delete(STOCK_TABLE, "_id=" + id, null);
                break;
            default:
                throw new UnsupportedOperationException("Pas encore implémenté");
        }

        return 0;
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
        return 0;
    }
}

谢谢你的帮助。

编辑:我尝试添加一个游标关闭但它没有改变任何东西...但是我有一个按钮可以删除数据库中的一行并且...如果我删除一行，那么我的 listView 中就再也看不到该行了但我可以看到我添加的一行之前看不到的......我想我只能在我的 listView 中显示 3 行，所以我觉得这是 listView 本身的问题。我正在检查 listView 的文档，看看我错过了什么......

编辑 2:这绝对是一个设计问题，我只显示了几个项目，因为我无法滚动浏览我的所有项目。这是包含我的 listView 的新 fragment 布局:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="layout.ViewCardEditor"
android:background="@android:color/darker_gray">

    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/listView" />

</FrameLayout>

之前，layout_height 被设置为 500dp 之类的值。但是现在我的 listView 很小，我可以滚动但是我的 listView 中的所有 TextView 都被窃听了，它们的内容显示来自其他 TextView 的内容并在我滚动时再次更改。就像 textView 的内容在其他 TextView 中随着我滚动一样。

编辑 3:我投票决定删除我的问题，因为我没有更多的错误，但是我的 listView 有一个新问题，它有一个有限的滚动:我可以看到 3 个项目和 4 个项目的顶部，我可以滚动一点有点……

Answer 1

您需要使用 ContentResolvers.notifyChange(...) 通知 Cursors 内容已更改方法。当您更新数据时，您需要在您的自定义 ContentProvider 中执行此操作。此调用允许注册更改通知的游标刷新其数据。