android selector RadioButton实现Tab功能

研究了好几天都一直有bug，今天终于弄出来了，开心~~

效果图如下：

说下大致思路：

首先利用radiobutton做菜单键，为button设置selector 

  1.创建xml文件

             在res下创建drawable 文件夹，在drawable文件夹下创建selector.xml

            selector.xml内容如下:   

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

              注： icon_diamond为未选中状态下图片， icon_diamond_press为选中状态下图片

PS:附上selector的一些属性。

/*

android:drawable 放一个drawable资源
android:state_pressed 是否按下，如一个按钮触摸或者点击。
android:state_focused 是否取得焦点，比如用户选择了一个文本框。
android:state_hovered 光标是否悬停，通常与focused state相同，它是4.0的新特性
android:state_selected 被选中，它与focus state并不完全一样，如一个list view 被选中的时候，它里面的各个子组件可能通过方向键，被选中了。
android:state_checkable 组件是否能被check。如：RadioButton是可以被check的。
android:state_checked 被checked了，如：一个RadioButton可以被check了。
android:state_enabled 能够接受触摸或者点击事件
android:state_activated 被激活
android:state_window_focused 应用程序是否在前台，当有通知栏被拉下来或者一个对话框弹出的时候应用程序就不在前台了

*/

为文字设置selector，在drawable文件夹下创建radiobtn_selector_color.xml

radiobtn_selector_color.xml

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

    2.将selector.xml设为RadioButton的背景       

页面布局：activity_main.xml

<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">    <RelativeLayout        android:id="@+id/ly_top_bar"        android:layout_width="match_parent"        android:layout_height="48dp">        <TextView            android:id="@+id/txt_topbar"            android:layout_width="match_parent"            android:layout_height="match_parent"            android:layout_centerInParent="true"            android:gravity="center"            android:text="乐蜂网"            android:textSize="18sp" />        <View            android:layout_width="match_parent"            android:layout_height="2dp"            android:background="#000000"            android:layout_alignParentBottom="true" />    </RelativeLayout>    <FrameLayout        android:id="@+id/main_content"        android:layout_width="fill_parent"        android:layout_height="0dp"        android:layout_weight="1" />    <RadioGroup        android:id="@+id/rg_tab_bar"        android:layout_width="match_parent"        android:layout_height="56dp"        android:layout_alignParentBottom="true"        android:orientation="horizontal">        <RadioButton            android:id="@+id/rb_channel"            android:layout_height="wrap_content"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_gravity="bottom"            android:background="#00000000"            android:button="@null"            android:checked="true"            android:drawableTop="@drawable/selector"            android:gravity="center_horizontal|bottom"            android:paddingTop="1dp"            android:text="特卖"            android:textColor="@drawable/radiobtn_selector_color" />        <RadioButton            android:id="@+id/rb_message"            android:layout_height="wrap_content"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_gravity="bottom"            android:background="#00000000"            android:button="@null"            android:drawableTop="@drawable/selector"            android:gravity="center_horizontal|bottom"            android:paddingTop="1dp"            android:text="商城"            android:textColor="@drawable/radiobtn_selector_color" />        <RadioButton            android:id="@+id/rb_better"            android:layout_height="wrap_content"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_gravity="bottom"            android:background="#00000000"            android:button="@null"            android:drawableTop="@drawable/selector"            android:gravity="center_horizontal|bottom"            android:paddingTop="1dp"            android:text="购物车"            android:textColor="@drawable/radiobtn_selector_color"  />        <RadioButton            android:id="@+id/rb_setting"            android:layout_height="wrap_content"            android:layout_width="0dp"            android:layout_weight="1"            android:layout_gravity="bottom"            android:background="#00000000"            android:button="@null"            android:drawableTop="@drawable/selector"            android:gravity="center_horizontal|bottom"            android:paddingTop="1dp"            android:text="我的蜂巢"            android:textColor="@drawable/radiobtn_selector_color"  />    </RadioGroup>    <View        android:id="@+id/div_tab_bar"        android:layout_width="match_parent"        android:layout_height="2px"        android:layout_above="@id/rg_tab_bar"        android:background="@color/colorPrimary" />    <android.support.v4.view.ViewPager        android:id="@+id/vpager"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_above="@id/div_tab_bar"        android:layout_below="@id/ly_top_bar" />

       这样就可以实现Tab功能，需要的注意的一点是， 使用Button时并不会出现选中状态

四个Fragment，类似于微信的主界面

Fragment1.java

package com.example.demo.myapplication;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;public class MyFragment1 extends Fragment {    public MyFragment1(){    }    @Override    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {        View view = inflater.inflate(R.layout.fg_content, container, false);        TextView content = (TextView) view.findViewById(R.id.content);        content.setText("第一个Fragment");        return view;    }}

MainActivity.java

package com.example.demo.myapplication;import android.os.Bundle;import android.support.v4.view.ViewPager;import android.support.v7.app.AppCompatActivity;import android.widget.RadioButton;import android.widget.RadioGroup;import android.widget.TextView;public class MainActivity extends AppCompatActivity implements RadioGroup.OnCheckedChangeListener,        ViewPager.OnPageChangeListener {    //UI Objects    private TextView txt_topbar;    private RadioGroup  rg_tab_bar;    private RadioButton rb_channel;    private RadioButton rb_message;    private RadioButton rb_better;    private RadioButton rb_setting;    private ViewPager vpager;    private MyFragmentPagerAdapter mAdapter;    //几个代表页面的常量    public static final int PAGE_ONE = 0;    public static final int PAGE_TWO = 1;    public static final int PAGE_THREE = 2;    public static final int PAGE_FOUR = 3;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mAdapter = new MyFragmentPagerAdapter(getSupportFragmentManager());        bindViews();        rb_channel.setChecked(true);    }    private void bindViews() {        txt_topbar = (TextView) findViewById(R.id.txt_topbar);        rg_tab_bar = (RadioGroup) findViewById(R.id.rg_tab_bar);        rb_channel = (RadioButton) findViewById(R.id.rb_channel);        rb_message = (RadioButton) findViewById(R.id.rb_message);        rb_better = (RadioButton) findViewById(R.id.rb_better);        rb_setting = (RadioButton) findViewById(R.id.rb_setting);        rg_tab_bar.setOnCheckedChangeListener(this);        vpager = (ViewPager) findViewById(R.id.vpager);        vpager.setAdapter(mAdapter);        vpager.setCurrentItem(0);        vpager.addOnPageChangeListener(this);    }    @Override    public void onCheckedChanged(RadioGroup group, int checkedId) {        switch (checkedId) {            case R.id.rb_channel:                vpager.setCurrentItem(PAGE_ONE);                break;            case R.id.rb_message:                vpager.setCurrentItem(PAGE_TWO);                break;            case R.id.rb_better:                vpager.setCurrentItem(PAGE_THREE);                break;            case R.id.rb_setting:                vpager.setCurrentItem(PAGE_FOUR);                break;        }    }    //重写ViewPager页面切换的处理方法    @Override    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {    }    @Override    public void onPageSelected(int position) {    }    @Override    public void onPageScrollStateChanged(int state) {        //state的状态有三个，0表示什么都没做，1正在滑动，2滑动完毕        if (state == 2) {            switch (vpager.getCurrentItem()) {                case PAGE_ONE:                    rb_channel.setChecked(true);                    break;                case PAGE_TWO:                    rb_message.setChecked(true);                    break;                case PAGE_THREE:                    rb_better.setChecked(true);                    break;                case PAGE_FOUR:                    rb_setting.setChecked(true);                    break;            }        }    }}