Fragment+RadioButton实现Tab页切换

• 总所周知，实现一个App的Tab页切换的方式有很多种。例如使用ViewPager+Fragment，RadioButton+Fragment。今天主要来利用RadioButton来实现。

首先我们绘制一个布局

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical"    android:id="@+id/activity_main"    android:background="@color/page_bg"    android:layout_width="match_parent"    android:layout_height="match_parent">    <FrameLayout        android:id="@+id/fl_content"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"/>    <RadioGroup        android:id="@+id/main_group"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:padding="5dp"        android:background="@color/white"        android:orientation="horizontal">        <RadioButton            android:id="@+id/rb_information"            android:button="@null"            android:checked="true"            android:text="资讯"            android:drawablePadding="3dp"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_height="wrap_content"            android:gravity="center"            android:drawableTop="@drawable/main_information_selector"            />        <RadioButton            android:id="@+id/rb_video"            android:button="@null"            android:text="短视频"            android:drawablePadding="3dp"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_height="wrap_content"            android:gravity="center"            android:drawableTop="@drawable/main_video_selector"            />        <RadioButton            android:id="@+id/rb_me"            android:button="@null"            android:text="我的"            android:drawablePadding="3dp"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_height="wrap_content"            android:gravity="center"            android:drawableTop="@drawable/main_me_selector"            />    </RadioGroup></LinearLayout>

好吧，直接java代码吧

package com.wj.gamingheadlines;import android.os.Bundle;import android.support.annotation.Nullable;import android.support.v4.app.Fragment;import android.support.v4.app.FragmentManager;import android.support.v4.app.FragmentTransaction;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.FrameLayout;import android.widget.RadioButton;import android.widget.RadioGroup;import com.wj.gamingheadlines.fragments.InformationFragment;import com.wj.gamingheadlines.fragments.MeFragment;import com.wj.gamingheadlines.fragments.VideoFragment;import java.lang.reflect.InvocationTargetException;import butterknife.BindView;import butterknife.ButterKnife;import butterknife.OnClick;/** * 主页面 */public class MainActivity extends AppCompatActivity {    @BindView(R.id.rb_information)    RadioButton rbInformation;    @BindView(R.id.rb_video)    RadioButton rbVideo;    @BindView(R.id.rb_me)    RadioButton rbMe;    private Fragment mShowFragment;    private FragmentManager fm;    @Override    protected void onCreate(@Nullable Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ButterKnife.bind(this);        fm=getSupportFragmentManager();        initCheck();    }    private void initCheck() {        FragmentTransaction transaction = fm.beginTransaction();        mShowFragment=new InformationFragment();        transaction.add(R.id.fl_content,mShowFragment,InformationFragment.TAG);        transaction.commit();    }    @OnClick({R.id.rb_information, R.id.rb_video, R.id.rb_me})    public void onViewClicked(View view) {        switch (view.getId()) {            case R.id.rb_information:                switchPages(InformationFragment.TAG,InformationFragment.class);                break;            case R.id.rb_video:                switchPages(VideoFragment.TAG,VideoFragment.class);                break;            case R.id.rb_me:                switchPages(MeFragment.TAG,MeFragment.class);                break;        }    }    //切换显示Fragment    private void switchPages(String tag, Class<? extends Fragment> cls) {//        FragmentManager fm = getSupportFragmentManager();        FragmentTransaction transaction = fm.beginTransaction();        //隐藏显示页面        transaction.hide(mShowFragment);        //根据TAG去FragmentManager寻找碎片        mShowFragment = fm.findFragmentByTag(tag);        if (mShowFragment != null) {            transaction.show(mShowFragment);        } else {            try {                //使用反射实例化一个对象                mShowFragment = cls.getConstructor().newInstance();            } catch (InstantiationException e) {                e.printStackTrace();            } catch (IllegalAccessException e) {                e.printStackTrace();            } catch (InvocationTargetException e) {                e.printStackTrace();            } catch (NoSuchMethodException e) {                e.printStackTrace();            }            transaction.add(R.id.fl_content, mShowFragment, tag);        }        transaction.commit();    }}

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• 其中使用的是ButterKnife，减少findViewById的繁复工作。切换是不是很简单，就是一个方法的事儿。