FragmentTabHost 图形布局不呈现 [英] FragmentTabHost graphical layout doesn't render

问题描述

简单的 android.support.v4.app.FragmentTabHost 的图形布局永远不会在 Eclipse 或 Android Studio 中呈现.
我得到的控制台错误始终如一:
渲染过程中引发的异常:没有已知标签为空的标签

The graphical layout for a simple android.support.v4.app.FragmentTabHost never renders in either Eclipse or Android Studio.
The Console error I get is consistently:
Exception raised during rendering: No tab known for tag null

我使用的是最基本的 XML 文件:

I'm using the most basic XML file:

<android.support.v4.app.FragmentTabHost
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/tabhost"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <TabWidget
            android:id="@android:id/tabs"
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="0"/>

        <FrameLayout
            android:id="@android:id/tabcontent"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:layout_weight="0"/>

        <FrameLayout
            android:id="@+id/realtabcontent"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"/>

    </LinearLayout>
</android.support.v4.app.FragmentTabHost>

但是出现同样的错误.

我只想在标签小部件和框架布局的上方或下方添加更多视图.
我不太在意看到标签内容；我只想查看我的其余布局 - 但问题是当 android.support.v4.app.FragmentTabHost 驻留在布局中.

I just wanted to add more views above or below the tab widget and frame layout.
I don't care so much about seeing the tab content; I just want to see the rest of my layout - but the problem is that NO OTHER VIEWS are rendered when a android.support.v4.app.FragmentTabHost resides in the layout.

我已阅读并尝试通过对这篇文章的回答来解决问题:
Android:带有 FragmentTabHost 的底部标签
但我不认为那是我的问题；我不想在底部放置 TabWidget.

I've read and tried to resolve the issue from the answer to this post:
Android: Tabs at the bottom with FragmentTabHost
but I don't think that that is my problem; I'm not looking to put a TabWidget on the bottom.

我的每个其他 XML 文件都可以完美打开.

Every other one of my XML files opens perfectly.

Android Studio 也出现同样的问题:

The same problem occurs in Android Studio:

推荐答案

我遇到了同样的渲染问题以及编译错误.我发现我在创建 Addtab 时没有传递 Fragment，从而解决了这个问题.您必须在 mTab​​Host.addTab 上传递至少一个片段.下面是工作代码.

I had the same rendering problem as well as compilation error. I fixed the problem by finding that I was not passing Fragment when i was creating Addtab. You must pass atleast one fragment on mTabHost.addTab. Below is the working code.

private FragmentTabHost mTabHost;
mTabHost = (FragmentTabHost)findViewById(android.R.id.tabhost);
            mTabHost.setup(HomeActivity.this, getSupportFragmentManager(), android.R.id.tabcontent);

            mTabHost.addTab(mTabHost.newTabSpec("home").setIndicator("Home"), HomeFragment.class, null);
            mTabHost.addTab(mTabHost.newTabSpec("mysheets").setIndicator("MySheets"));
            mTabHost.addTab(mTabHost.newTabSpec("bookmarks").setIndicator("Bookmarks"));

这篇关于FragmentTabHost 图形布局不呈现的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！