android - PagerTabStrip 缺少选项卡导航面板

Question

我现在正在学习创建选项卡式 Activity ，并且我选择了 PagerTabStrip 来使用。但是现在当我创建 fragment ，将它们分配给适配器，并将适配器分配给 ViewPager 时，PagerTabStrip 的 Tab 导航面板丢失了

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.player.pagertabstrip.MainActivity"
    android:orientation="vertical">
    <android.support.v4.view.ViewPager
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/viewPager">
        <android.support.v4.view.PagerTabStrip
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="top" />
    </android.support.v4.view.ViewPager>
</LinearLayout>

PageFragment.java

import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;


public class PageFragment extends Fragment {
    private static final String ARG_PAGE_NUMBER = "page_number";

    public PageFragment() {
    }

    public static PageFragment newInstance(int page) {
        PageFragment fragment = new PageFragment();
        Bundle args = new Bundle();
        args.putInt(ARG_PAGE_NUMBER, page);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_page_layout, container, false);

        TextView txt = (TextView) rootView.findViewById(R.id.page_number_label);
        int page = getArguments().getInt(ARG_PAGE_NUMBER, -1);
        txt.setText(String.format("Page %d", page));

        return rootView;
    }
}

fragment_page_layout.xml

<?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:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context="com.example.player.pagertabstrip.PageFragment">

    <TextView android:id="@+id/page_number_label"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="@android:style/TextAppearance.Large"
        android:gravity="center"
        android:layout_centerVertical="true" />

</RelativeLayout>

MainActivity.java

import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TabsPagerAdapter tabsPagerAdapter = new TabsPagerAdapter(getSupportFragmentManager());
        ViewPager viewPager = (ViewPager)findViewById(R.id.viewPager);
        viewPager.setAdapter(tabsPagerAdapter);
    }
}

和无标签导航的截图:-

Answer 1

所以，它似乎是 com.android.support:appcompat-v7:24.0.0 库中的错误。我找到了 2 种方法来解决这个问题。

First:

您必须降级项目中使用的库。在你的 gradle 文件中，将 compile 'com.android.support:appcompat-v7:24.0.0' 替换为 compile 'com.android.support:appcompat-v7:23.2.0'

Second:

您可以通过其父级的 LayoutParams 访问来更改子 PagerTabStrip 的属性

((ViewPager.LayoutParams) pagerTabStrip.getLayoutParams()).isDecor = true;