21 RadioGroup ListFragment

• 结构
  
  

MainActivity.java

package com.qf.day21_radiogroupfragment_demo3;

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

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;

public class MainActivity extends FragmentActivity {

    private RadioGroup rgMain;

    //Fragment数据源
    private List<Fragment> list = new ArrayList<Fragment>();

    private RadioButton[] rbs;

    private String[] titles={"news","happy","dz","cj"};

    private int currentIndex =0;//当前展示的Fragment

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        rgMain = (RadioGroup) findViewById(R.id.rg_main);

        initData();
        initTab();
    }

    //初始化标签
    private void initTab(){
        //改变标签内容
        rbs = new RadioButton[rgMain.getChildCount()];
        for(int i=0;i<rgMain.getChildCount();i++){
            rbs[i] = (RadioButton) rgMain.getChildAt(i);
            rbs[i].setText(titles[i]);
        }

        //点击按钮进行替换
        rgMain.setOnCheckedChangeListener(new OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                // TODO Auto-generated method stub
                for(int i=0;i<rgMain.getChildCount();i++){
                    if(rbs[i].getId() == checkedId){//当前按钮被点击
                        //开始替换
                        //replaceFragment(i);
                        switchFragment(i);
                    }

                }
            }
        });

    }
    //replace  缺点  影响性能
    public void replaceFragment(int index){
        MyFragment myFragment = MyFragment.getInstance(index+1);
        getSupportFragmentManager().
        beginTransaction().
        replace(R.id.layout_content_id, list.get(index)).commit();

    }

    //替换   使用 show() 和hide() 方法  减少性能开销
    public void  switchFragment(int targetIndex){

        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();

        //点击的Fragment(目标)
        Fragment targetFragment = list.get(targetIndex);
        //当前的Fragment
        Fragment currentFragment = list.get(currentIndex);

        //点击的 按钮对象的Fragment 存在    show()展示出来  隐藏当前的Fragment
        if(!targetFragment.isAdded()){
            transaction.add(R.id.layout_content_id, targetFragment).hide(currentFragment).commit();
        }else{
            transaction.show(targetFragment).hide(currentFragment).commit();
        }

        //当前展示的Fragment就是点击替换的Fragment
        currentIndex = targetIndex;

    }

    //初始化数据
    private void initData(){
        for(int i=0;i<rgMain.getChildCount();i++){
            MyFragment myFragment = MyFragment.getInstance(i+1);
            list.add(myFragment);
        }
        //程序运行  默认展示第一个Fragment
        getSupportFragmentManager().
        beginTransaction().
        add(R.id.layout_content_id, list.get(0)).commit();
    }

}

MyFragment.java

package com.qf.day21_radiogroupfragment_demo3;

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

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;

public class MainActivity extends FragmentActivity {

    private RadioGroup rgMain;

    //Fragment数据源
    private List<Fragment> list = new ArrayList<Fragment>();

    private RadioButton[] rbs;

    private String[] titles={"news","happy","dz","cj"};

    private int currentIndex =0;//当前展示的Fragment

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        rgMain = (RadioGroup) findViewById(R.id.rg_main);

        initData();
        initTab();
    }

    //初始化标签
    private void initTab(){
        //改变标签内容
        rbs = new RadioButton[rgMain.getChildCount()];
        for(int i=0;i<rgMain.getChildCount();i++){
            rbs[i] = (RadioButton) rgMain.getChildAt(i);
            rbs[i].setText(titles[i]);
        }

        //点击按钮进行替换
        rgMain.setOnCheckedChangeListener(new OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                // TODO Auto-generated method stub
                for(int i=0;i<rgMain.getChildCount();i++){
                    if(rbs[i].getId() == checkedId){//当前按钮被点击
                        //开始替换
                        //replaceFragment(i);
                        switchFragment(i);
                    }

                }
            }
        });

    }
    //replace  缺点  影响性能
    public void replaceFragment(int index){
        MyFragment myFragment = MyFragment.getInstance(index+1);
        getSupportFragmentManager().
        beginTransaction().
        replace(R.id.layout_content_id, list.get(index)).commit();

    }

    //替换   使用 show() 和hide() 方法  减少性能开销
    public void  switchFragment(int targetIndex){

        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();

        //点击的Fragment(目标)
        Fragment targetFragment = list.get(targetIndex);
        //当前的Fragment
        Fragment currentFragment = list.get(currentIndex);

        //点击的 按钮对象的Fragment 存在    show()展示出来  隐藏当前的Fragment
        if(!targetFragment.isAdded()){
            transaction.add(R.id.layout_content_id, targetFragment).hide(currentFragment).commit();
        }else{
            transaction.show(targetFragment).hide(currentFragment).commit();
        }

        //当前展示的Fragment就是点击替换的Fragment
        currentIndex = targetIndex;

    }

    //初始化数据
    private void initData(){
        for(int i=0;i<rgMain.getChildCount();i++){
            MyFragment myFragment = MyFragment.getInstance(i+1);
            list.add(myFragment);
        }
        //程序运行  默认展示第一个Fragment
        getSupportFragmentManager().
        beginTransaction().
        add(R.id.layout_content_id, list.get(0)).commit();
    }

}

selecte_main.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:state_checked="true" android:drawable="@android:drawable/ic_menu_add"></item>
    <item android:state_checked="false" android:drawable="@android:drawable/ic_menu_call"></item>

</selector>

activity_main.xml

<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:orientation="vertical"
    tools:context=".MainActivity" >

    <RadioGroup
        android:id="@+id/rg_main"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <RadioButton
            android:id="@+id/rb1"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selecte_main"
            android:gravity="center"
            android:checked="true"
            android:text="新闻" />

        <RadioButton
             android:id="@+id/rb2"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selecte_main"
            android:gravity="center"
            android:text="娱乐" />

        <RadioButton
             android:id="@+id/rb3"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selecte_main"
            android:gravity="center"
            android:text="体育" />

        <RadioButton
             android:id="@+id/rb4"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:button="@null"
            android:drawableTop="@drawable/selecte_main"
            android:gravity="center"
            android:text="财经" />
    </RadioGroup>

    <FrameLayout
        android:id="@+id/layout_content_id"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        ></FrameLayout>

</LinearLayout>

fragment_layout.xml

<?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:id="@+id/tv_show"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textColor="#f00"
        android:text="AAA"
        />
    <ListView
        android:id="@android:id/list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        ></ListView>

</LinearLayout>

item.xml

<?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="match_parent"
     >
    <ImageView
        android:id="@+id/iv_item"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher"
        />
    <TextView
        android:id="@+id/title_item"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/iv_item"
        android:text="name"
        />
    <TextView
        android:id="@+id/content_item"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/iv_item"
        android:text="aaa"
        android:layout_alignBottom="@id/iv_item"
        />

</RelativeLayout>