小编LON*_*MAN的帖子

我想在导航抽屉中放置底部ListView的TextView.抛出java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams cannot be cast to android.support.v4.widget.DrawerLayout$LayoutParams

main.xml中

    <android.support.v4.widget.DrawerLayout             xmlns:android="http://schemas.android.com/apk/res/android"
                                        android:id="@+id/drawer_layout"
                                        android:layout_width="match_parent"
                                        android:layout_height="match_parent"
    >

    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/content_frame"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:paddingLeft="@dimen/activity_horizontal_margin"
        android:paddingRight="@dimen/activity_horizontal_margin"
        android:paddingTop="0dp"
        android:paddingBottom="4dp"
    />

    <LinearLayout
        android:orientation="vertical"
        android:layout_width="240dp"
        android:layout_height="match_parent"
        android:id="@+id/left_drawer"
        android:layout_gravity="start"
        >

        <ListView
            android:id="@+id/left_menu"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:choiceMode="singleChoice"
            android:dividerHeight="0.1dp"
            android:background="#111"
            android:divider="#FFF"
            />

        <TextView
            android:id="@+id/joke_text1"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:textSize="16sp"
            android:lineSpacingExtra="5sp"
            android:text="AAAAAA"
            />
    </LinearLayout>

</android.support.v4.widget.DrawerLayout>

和java代码:

// Getting reference to the DrawerLayout
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerLinear = (LinearLayout) findViewById(R.id.left_drawer);

leftMenuItems = getResources().getStringArray(R.array.leftMenuItems);

mDrawerList = (ListView) findViewById(R.id.left_menu);
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());

// set a custom shadow …

我正在开发应用程序，在应用程序启动时，我从 Rest 服务下载类别和帖子，以便将它们存储在 SQLite 数据库中。我有几个问题：

1. 如何确定哪个对象是类别和哪个帖子？或者我如何才能访问它们？objects变量很奇怪。
2. 我应该将使用 Room 库在数据库中插入项目的代码放在哪里？
3. 我需要为每个帖子下载图片，我应该在哪里下载？

代码：

ItemsApi client = this.getClient(); // Retrofit2

List<Observable<?>> requests = new ArrayList<>();
requests.add(client.getCategories());
requests.add(client.getPosts());

Observable<Object> combined = Observable.zip(
        requests,
        new Function<Object[], Object>() {
            @Override
            public Object apply(Object[] objects) throws Exception {
                Timber.d("Length %s", objects.length); // Length 2
                Timber.d("objects.getClass() %s", objects.getClass()); // objects.getClass() class [Ljava.lang.Object;

                return new Object();
            }
        });

Disposable disposable = combined.subscribe(
        new Consumer<Object>() {
            @Override
            public void accept(Object o) throws Exception {
               Timber.d("Object %s", o.toString());
            } …