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Fragment教程之Fragment基本使用

Fragment教程之Fragment基本使用

作者: 手指乐 | 来源:发表于2019-08-14 15:55 被阅读0次

    静态使用Fragment

    主要有以下两个步骤:
    1、继承Fragment,重写onCreateView决定Fragment的布局
    2、在Activity中声明此Fragment,就当和普通的View一样

    下面展示一个例子(我使用2个Fragment作为Activity的布局,一个Fragment用于标题布局,一个Fragment用于内容布局)

    TitleFragment的布局文件:

    <?xml version="1.0" encoding="utf-8"?>  
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
        android:layout_width="match_parent"  
        android:layout_height="45dp"  
        android:background="@drawable/title_bar" >  
      
        <ImageButton  
            android:id="@+id/id_title_left_btn"  
            android:layout_width="wrap_content"  
            android:layout_height="wrap_content"  
            android:layout_centerVertical="true"  
            android:layout_marginLeft="3dp"  
            android:background="@drawable/showleft_selector" />  
      
        <TextView  
            android:layout_width="fill_parent"  
            android:layout_height="fill_parent"  
            android:gravity="center"  
            android:text="我不是微信"  
            android:textColor="#fff"  
            android:textSize="20sp"  
            android:textStyle="bold" />  
      
    </RelativeLayout>  
    

    TitleFragment:

    package com.zhy.zhy_fragments;  
      
    import android.app.Fragment;  
    import android.os.Bundle;  
    import android.view.LayoutInflater;  
    import android.view.View;  
    import android.view.View.OnClickListener;  
    import android.view.ViewGroup;  
    import android.widget.ImageButton;  
    import android.widget.Toast;  
      
    public class TitleFragment extends Fragment  
    {  
      
        private ImageButton mLeftMenu;  
      
        @Override  
        public View onCreateView(LayoutInflater inflater, ViewGroup container,  
                Bundle savedInstanceState)  
        {  
            View view = inflater.inflate(R.layout.fragment_title, container, false);  
            mLeftMenu = (ImageButton) view.findViewById(R.id.id_title_left_btn);  
            mLeftMenu.setOnClickListener(new OnClickListener()  
            {  
                @Override  
                public void onClick(View v)  
                {  
                    Toast.makeText(getActivity(),  
                            "i am an ImageButton in TitleFragment ! ",  
                            Toast.LENGTH_SHORT).show();  
                }  
            });  
            return view;  
        }  
    }  
    

    ContentFragment布局:

    <?xml version="1.0" encoding="utf-8"?>  
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
        android:layout_width="match_parent"  
        android:layout_height="match_parent"  
        android:orientation="vertical" >  
      
        <TextView  
            android:layout_width="fill_parent"  
            android:layout_height="fill_parent"  
            android:gravity="center"  
            android:text="使用Fragment做主面板"  
            android:textSize="20sp"  
            android:textStyle="bold" />  
      
    </LinearLayout>  
    

    ContentFragment:

    package com.zhy.zhy_fragments;  
      
    import android.app.Fragment;  
    import android.os.Bundle;  
    import android.view.LayoutInflater;  
    import android.view.View;  
    import android.view.ViewGroup;  
      
    public class ContentFragment extends Fragment  
    {  
      
        @Override  
        public View onCreateView(LayoutInflater inflater, ViewGroup container,  
                Bundle savedInstanceState)  
        {  
            return inflater.inflate(R.layout.fragment_content, container, false);  
        }  
      
    }  
    

    MainActivity:

    package com.zhy.zhy_fragments;  
      
    import android.app.Activity;  
    import android.os.Bundle;  
    import android.view.Window;  
      
    public class MainActivity extends Activity  
    {  
      
        @Override  
        protected void onCreate(Bundle savedInstanceState)  
        {  
            super.onCreate(savedInstanceState);  
            requestWindowFeature(Window.FEATURE_NO_TITLE);  
            setContentView(R.layout.activity_main);  
        }  
      
    }  
    

    MainActivity布局文件:

    <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" >  
      
        <fragment  
            android:id="@+id/id_fragment_title"  
            android:name="com.zhy.zhy_fragments.TitleFragment"  
            android:layout_width="fill_parent"  
            android:layout_height="45dp" />  
      
        <fragment  
            android:layout_below="@id/id_fragment_title"  
            android:id="@+id/id_fragment_content"  
            android:name="com.zhy.zhy_fragments.ContentFragment"  
            android:layout_width="fill_parent"  
            android:layout_height="fill_parent" />  
      
    </RelativeLayout>  
    

    注意:fragment首字母小写,一定要给id
    是不是把Fragment当成普通的View一样声明在Activity的布局文件中,然后所有控件的事件处理等代码都由各自的Fragment去处理,瞬间觉得Activity好干净有木有~~代码的可读性、复用性以及可维护性是不是瞬间提升了

    动态的使用Fragment

    我们实现以下效果:

    image
    activity布局代码:
    <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" >  
      
        <fragment  
            android:id="@+id/id_fragment_title"  
            android:name="com.zhy.zhy_fragments.TitleFragment"  
            android:layout_width="fill_parent"  
            android:layout_height="45dp" />  
      
        <include  
            android:id="@+id/id_ly_bottombar"  
            android:layout_width="fill_parent"  
            android:layout_height="55dp"  
            android:layout_alignParentBottom="true"  
            layout="@layout/bottombar" />  
      
        <FrameLayout  
            android:id="@+id/id_content"  
            android:layout_width="fill_parent"  
            android:layout_height="fill_parent"  
            android:layout_above="@id/id_ly_bottombar"  
            android:layout_below="@id/id_fragment_title" />  
      
    </RelativeLayout>  
    

    activity代码:

    package com.zhy.zhy_fragments;  
      
    import android.app.Activity;  
    import android.app.FragmentManager;  
    import android.app.FragmentTransaction;  
    import android.os.Bundle;  
    import android.view.View;  
    import android.view.View.OnClickListener;  
    import android.view.Window;  
    import android.widget.LinearLayout;  
      
    public class MainActivity extends Activity implements OnClickListener  
    {  
        private LinearLayout mTabWeixin;  
        private LinearLayout mTabFriend;  
      
        private ContentFragment mWeixin;  
        private FriendFragment mFriend;  
      
        @Override  
        protected void onCreate(Bundle savedInstanceState)  
        {  
            super.onCreate(savedInstanceState);  
            requestWindowFeature(Window.FEATURE_NO_TITLE);  
            setContentView(R.layout.activity_main);  
      
            // 初始化控件和声明事件  
            mTabWeixin = (LinearLayout) findViewById(R.id.tab_bottom_weixin);  
            mTabFriend = (LinearLayout) findViewById(R.id.tab_bottom_friend);  
            mTabWeixin.setOnClickListener(this);  
            mTabFriend.setOnClickListener(this);  
      
            // 设置默认的Fragment  
            setDefaultFragment();  
        }  
      
        private void setDefaultFragment()  
        {  
            FragmentManager fm = getFragmentManager();  
            FragmentTransaction transaction = fm.beginTransaction();  
            mWeixin = new ContentFragment();  
            transaction.replace(R.id.id_content, mWeixin);  
            transaction.commit();  
        }  
      
        @Override  
        public void onClick(View v)  
        {  
            FragmentManager fm = getFragmentManager();  
            // 开启Fragment事务  
            FragmentTransaction transaction = fm.beginTransaction();  
      
            switch (v.getId())  
            {  
            case R.id.tab_bottom_weixin:  
                if (mWeixin == null)  
                {  
                    mWeixin = new ContentFragment();  
                }  
                // 使用当前Fragment的布局替代id_content的控件  
                transaction.replace(R.id.id_content, mWeixin);  
                break;  
            case R.id.tab_bottom_friend:  
                if (mFriend == null)  
                {  
                    mFriend = new FriendFragment();  
                }  
                transaction.replace(R.id.id_content, mFriend);  
                break;  
            }  
            // transaction.addToBackStack();  
            // 事务提交  
            transaction.commit();  
        }  
      
    } 
    

    Fragment代码跟上面静态使用类似

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        本文标题:Fragment教程之Fragment基本使用

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