Android 用显示隐藏完成fragment切换

版权声明：未经本人允许，转载需要注明出处 https://blog.csdn.net/nazicsdn/article/details/83062531

实现fragment的方法有很多，例如FragmentTabHost，replace，实现fragment切换，今天我为大家介绍一个显示隐藏的方法。

这个就是实现显示隐藏的运行类，简单方便，不会出现切换的时候，这个界面的布局复用到下一个界面

package cn.bgs.fragment1;

import cn.bgs.fragment1.fragment.HomeFragment;
import cn.bgs.fragment1.fragment.JPFragment;
import cn.bgs.fragment1.fragment.TJFragment;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.TextView;

public class MainActivity extends FragmentActivity implements OnClickListener {
	private TextView mHome,mTuijian,mJingpin;//三个按钮
	//创建三个碎片的对象
	private HomeFragment mHomeFragment;
	private JPFragment mJPFragment;
	private TJFragment mTJFragment;
	//创建碎片管理器
	private FragmentManager manager;//碎片管理器
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		manager=getSupportFragmentManager();//获取碎片管理器
		initView();
		goneFragment();
		//默认到第二个碎片
		selectFragment(R.id.tuijian_frag);
	}
	private void initView() {
		mHome=(TextView) findViewById(R.id.first_frag);
		mTuijian=(TextView) findViewById(R.id.tuijian_frag);
		mJingpin=(TextView) findViewById(R.id.jingpin_frag);
		mHome.setOnClickListener(this);
		mTuijian.setOnClickListener(this);
		mJingpin.setOnClickListener(this);
	}
	@Override
	public void onClick(View v) {
		int ID=v.getId();
		goneFragment();
		selectFragment(ID);
	}
	//根据ID选择碎片的方法
	private void selectFragment(int ID){
		//创建碎片事务管理  每一次碎片的显示与隐藏都要通过事务管理来操作
		FragmentTransaction ft=manager.beginTransaction();
		//操作：碎片为空 创建添加
		//     碎片不为空，直接显示
		switch (ID) {
		case R.id.first_frag:
			if(mHomeFragment==null){//为空，创建
				mHomeFragment=new HomeFragment();//创建
				ft.add(R.id.frag_group, mHomeFragment);//将碎片添加到专门存放碎片的容器中
			}else{
				ft.show(mHomeFragment);//不为空，直接显示
			}
			break;

		case R.id.tuijian_frag:
			if(mTJFragment==null){
				mTJFragment=new TJFragment();
				ft.add(R.id.frag_group, mTJFragment);
			}else{
				ft.show(mTJFragment);
			}
			break;
			
		case R.id.jingpin_frag:
			if(mJPFragment==null){
				mJPFragment=new JPFragment();
				ft.add(R.id.frag_group, mJPFragment);
			}else{
				ft.show(mJPFragment);
			}
			break;
		}
		ft.commit();//提交   一定一定要提交
	}
	//隐藏所有碎片的饿方法
	private void goneFragment(){
		FragmentTransaction ft=manager.beginTransaction();
		if(mHomeFragment!=null){
			ft.hide(mHomeFragment);
		}
		if(mTJFragment!=null){
			ft.hide(mTJFragment);
		}
		if(mJPFragment!=null){
			ft.hide(mJPFragment);
		}
		ft.commit();
	}
}

下面是几个frament，我也为大家展示一下：

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

/*
 * Fragment:碎片    1.继承自Fragment（V4包下）
 * 				 2.重写下面的oncontentView的方法
 * */
public class HomeFragment extends Fragment{
	
	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		//用java代码实现布局        动态布局
		TextView tv=new TextView(getActivity());
		tv.setText("我是首页！！！");
		tv.setTextSize(30);
		return tv;
	}
}

import cn.bgs.fragment1.R;

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

public class JPFragment extends Fragment{
	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		View v=LayoutInflater.from(getActivity()).inflate(R.layout.jingpin_fragment, null);
		return v;
	}
}

import cn.bgs.fragment1.R;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class TJFragment extends Fragment{
	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		View v=View.inflate(getActivity(), R.layout.tuijian_frgment, null);
		
		return v;
	}
}

下面是Mainactivity的布局：

<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"
    tools:context=".MainActivity" >
	
    <LinearLayout
        android:id="@+id/bottom_linear"
        android:layout_width="match_parent"
        android:layout_height="45dp"
        android:background="#28c8b7"
        android:gravity="center"
        android:orientation="horizontal" 
        android:layout_alignParentBottom="true"
        >

        <TextView
            android:id="@+id/first_frag"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:gravity="center"
            android:text="首页"
            android:textSize="18sp" />

        <TextView
            android:id="@+id/tuijian_frag"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:gravity="center"
            android:text="推荐"
            android:textSize="18sp" />

        <TextView
            android:id="@+id/jingpin_frag"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:gravity="center"
            android:text="精品"
            android:textSize="18sp" />
    </LinearLayout>
	<LinearLayout 
	    android:id="@+id/frag_group"
	    android:layout_width="match_parent"
	    android:layout_height="match_parent"
	    android:layout_above="@id/bottom_linear"
	    />
</RelativeLayout>

<?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" >
    <ImageView 
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/ic_launcher"
        />

</LinearLayout>

<?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" >
    <ImageView 
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/aaaaaa"
        android:scaleType="fitXY"
        />

</LinearLayout>