Question

我的架构的一部分如图所示： enter image description here

联结表会映射哪些项目属于哪个类别，“特色”列将该项目标记为该类别中的特色。

我需要做的是获取特定类别中所有项目的列表，包括联结表中的“featured”属性，并将该数据传递给gridview。

我已经为private RecyclerView recyclerView; public static final String PREF_FILE_NAME="testpref"; public static final String KEY_USER_LEARNED_DRAWER="user_learned_drawer"; private ActionBarDrawerToggle mDrawerToggle; private DrawerLayout mDrawerLayout; private View containerView; private MichaelAdapter adapter; private boolean mUserLearnedDrawer; private boolean mFromSavedInstanceState; public NavigationDrawerFragment() { // Required empty public constructor } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mUserLearnedDrawer=Boolean.valueOf(readFromPreference(getActivity(),KEY_USER_LEARNED_DRAWER,"false")); if (savedInstanceState!=null){ mFromSavedInstanceState=true; } } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { // Inflate the layout for this fragment View layout=inflater.inflate(R.layout.fragment_navigation_drawer, container, false); recyclerView=(RecyclerView)layout.findViewById(R.id.drawerList); adapter = new MichaelAdapter(getActivity(), getData()); recyclerView.setAdapter(adapter); recyclerView.setLayoutManager(new LinearLayoutManager(getActivity())); return layout; } public static List<information> getData() { List<information> data = new ArrayList<>(); int[] icons = {R.drawable.ic_podcasts, R.drawable.ic_magazine}; String[] titles = {"Podcast", "Magazine"}; for (int i = 0; i< titles.length && i< icons.length; i++) ; { information current=new information(); current.iconId=icons[i]; current.title=titles[i]; data.add(current); } return data; } public void setUp(int fragmentId, DrawerLayout drawerLayout, Toolbar toolbar) { containerView=getActivity().findViewById(fragmentId); mDrawerLayout=drawerLayout; mDrawerToggle=new ActionBarDrawerToggle(getActivity(),drawerLayout,toolbar,R.string.draw_open, R.string.draw_close){ @Override public void onDrawerOpened(View drawerView) { super.onDrawerOpened(drawerView); if(!mUserLearnedDrawer){ mUserLearnedDrawer=true; saveToPreference(getActivity(),KEY_USER_LEARNED_DRAWER,mUserLearnedDrawer+""); } getActivity().invalidateOptionsMenu(); } @Override public void onDrawerClosed(View drawerView) { super.onDrawerClosed(drawerView); getActivity().invalidateOptionsMenu(); } }; if (!mUserLearnedDrawer&& !mFromSavedInstanceState){ mDrawerLayout.openDrawer(containerView); } mDrawerLayout.setDrawerListener(mDrawerToggle); mDrawerLayout.post(new Runnable() { @Override public void run() { mDrawerToggle.syncState(); } }); } public static void saveToPreference(Context context,String preferenceName,String preferenceValue){ SharedPreferences sharedPreferences=context.getSharedPreferences(PREF_FILE_NAME,Context.MODE_PRIVATE); SharedPreferences.Editor editor=sharedPreferences.edit(); editor.putString(preferenceName,preferenceValue); editor.apply(); } public static String readFromPreference(Context context,String preferenceName,String defaultvalue){ SharedPreferences sharedPreferences=context.getSharedPreferences(PREF_FILE_NAME,Context.MODE_PRIVATE); return sharedPreferences.getString(preferenceName,defaultvalue); }表创建了一个模型并尝试实现了提议的解决方案here但是如何访问并将数据传递到gridview中？

类别模型

category_item

类别搜索模型

public function getCategoryItems()
{
    return $this->hasMany(CategoryItem::className(), ['category_id' => 'id']);
}

public function getItems()
{
    return $this->hasMany(Item::className(), ['id' => 'item_id'])->viaTable('{{%category_item}}', ['category_id' => 'id']);
}

项目模型

public function search($params)
{
    $query = Category::find()->with('items')->with('categoryItems');

    $dataProvider = new ActiveDataProvider([
        'query' => $query,
    ]);

    $this->load($params);

    if (!$this->validate()) {
        return $dataProvider;
    }

    $query->andFilterWhere([
        'id' => $this->id,
        'type' => $this->type,
    ]);

    $query->andFilterWhere(['like', 'title', $this->title])
        ->andFilterWhere(['like', 'description', $this->description]);

    return $dataProvider;
}

控制器

public function getItemCategories()
{
    return $this->hasMany(CategoryItem::className(), ['item_id' => 'id']);
}

public function getCategories()
{
    return $this->hasMany(Category::className(), ['id' => 'category_id'])->viaTable('{{%category_item}}', ['item_id' => 'id']);
}

查看

public function actionCategory($id = null)
{
    if($id == null) {
        $dataProvider = new ActiveDataProvider([
            'query' => Category::find()->all(),
        ]);

        return $this->render('category', [
                'dataProvider' => $dataProvider,
        ]);
    } else {

        $category = Category::findOne($id);

        if($category) {
            $searchModel = new CategorySearch();

            $itemsDataProvider = new ActiveDataProvider([
                'query' =>  $searchModel->search(['CategorySearch'=>['id'=>$id]]),
            ]);

            return $this->render('editCategory', [
                'itemsDataProvider' => $itemsDataProvider
                'model' => $category,
            ]);
        } else {
            throw new NotFoundHttpException('The requested page does not exist.');
        }
    }
}

通常，视图文件是试图找到解决方案的混合搭配。 TagFeaturedItem模型来自视图的先前版本，请参阅here

Answer 1

在我看来，您的项目中可能存在一些我不会探索的设计缺陷;我将讨论如何将相关数据导入gridview的问题。

您可以在gridview中创建自定义列，然后获取相关数据，您可以将这样的内容添加到gridview列数组中：

    [
            'label'=>'featured',
            'format'=>'raw',
            'value'=>function($data)
            {
                $categories = $data->categories; 

                $content = "";
                foreach($categories as $category)
                    $content .= $category->title."<br/>";

                return $content;
            }
    ],

请注意，$data表示数据提供程序返回的模型，在上面的示例中是项目模型。

Yii2从联结表中获取列并在gridview中使用

1 个答案: