張萌&韓墨羽——Fragment+ViewPager+TabLayout

Fragment+ViewPager+TabLayout

TabLayout的介紹

Tablayout繼承自HorizontalScrollView，用作頁面切換指示器，因使用簡便功能強大而廣泛使用在App中。
1 ,引入 com.android.support:design
TabLayout 是屬於 com.android.support:design 包的控件，所以需要依賴該包

implementation 'com.android.support:design:28.0.0'

2,MainActivity的xml文件的創建

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <android.support.design.widget.TabLayout
        android:id="@+id/tab_id"
        app:tabSelectedTextColor="#E5AF35"
        app:tabTextColor="#969696"
        app:tabIndicatorColor="#E5AF35"
        app:tabIndicatorHeight="5dp"
        app:tabMode="scrollable"
        android:layout_weight="1"
        android:layout_width="match_parent"
        android:layout_height="0dp">

    </android.support.design.widget.TabLayout>

    <android.support.v4.view.ViewPager
        android:id="@+id/vp_id"
        android:layout_weight="8"
        android:layout_width="match_parent"
        android:layout_height="0dp">

    </android.support.v4.view.ViewPager>
</LinearLayout>

從 xml 佈局文件看，根佈局爲一個垂直的線性佈局，包含 TabLayout 和 ViewPager。重點看一下 TabLayout 的幾個常用屬性值

app:tabBackground 標籤佈局的背景色
app:tabIndicatorColor 指示器的顏色
app:tabIndicatorHeight 指示器的高度（如果不需要指示器可以設置爲0dp）
app:tabMode 顯示模式：默認 fixed（固定），scrollable（可橫向滾動）
app:tabPadding 標籤內邊距
app:tabSelectedTextColor 標籤選中的文本顏色
app:tabTextAppearance 標籤文本樣式
app:tabTextColor 標籤未選中的文本顏色

3,Java代碼：MainActivity.java

package com.example.day007;

import android.support.annotation.Nullable;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Window;

import com.example.day007.adapter.MyFragmentAdapter;
import com.example.day007.fragment.OneFragment;
import com.example.day007.fragment.TwoFragment;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private TabLayout tabId;
    private ViewPager vpId;

    private List<Fragment> list = new ArrayList<>();
    private List<String> titles = new ArrayList<>();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        supportRequestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);

        tabId = findViewById(R.id.tab_id);
        vpId = findViewById(R.id.vp_id);
        
        list.add(new OneFragment());
        list.add(new TwoFragment());
        list.add(new OneFragment());
        list.add(new TwoFragment());
       
        titles.add("視頻");
        titles.add("新聞");
        titles.add("圖片");
        titles.add("留言");
        
        MyFragmentAdapter myFragmentAdapter = new MyFragmentAdapter(getSupportFragmentManager(), list, titles);
        vpId.setAdapter(myFragmentAdapter);

        //把viewPager和tabLayout綁定在一起,註釋掉看看效果.
        tabId.setupWithViewPager(vpId);
    }
}

4,適配器代碼：MyFragmentAdapter.java

package com.example.day007.adapter;

import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.view.ViewPager;

import java.util.ArrayList;
import java.util.List;

/**
 * ${FENG}
 * 2019-07-11
 */
public class MyFragmentAdapter extends FragmentStatePagerAdapter {
    private List<Fragment> list;
    private List<String> titles;

    public MyFragmentAdapter(FragmentManager fm, List<Fragment> list, List<String> titles) {
        super(fm);
        this.list = list;
        this.titles = titles;
    }

    @Override
    public int getCount() {
        return list.size();
    }

    @Override
    public Fragment getItem(int i) {
        return list.get(i);
    }

	//返回與viewpage關聯以後的tablayot的內容
    @Nullable
    @Override
    public CharSequence getPageTitle(int position) {
        return titles.get(position);
    }
}

5,Fragment創建一個右鍵帶佈局的就搞定,不用其他改變.

/**
 * A simple {@link Fragment} subclass.
 */
public class OneFragment extends Fragment {
    public OneFragment() {
        // Required empty public constructor
    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_one, container, false);
    }
}