先看下实现效果图

MainActivity代码

public class MainActivity extends BaseActivity implementsRadioGroup.OnCheckedChangeListener {private RadioGroup radioGroup;private FrameLayout fragmentRoot;private HomeFragment homeFragment;private CardFragment cardFragment;private CollectionFragment collectionFragment;private SettingFragment settingFragment;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN);//软键盘弹出后页面整体上移initView();showFragment(0);}private void initView() {radioGroup = (RadioGroup) findViewById(R.id.bottomRg);radioGroup.setOnCheckedChangeListener(this);fragmentRoot = (FrameLayout) findViewById(R.id.fragmentRoot);homeFragment = new HomeFragment();cardFragment=new CardFragment();collectionFragment=new CollectionFragment();settingFragment=new SettingFragment();}private void showFragment(int index) {Fragment fragment = null;switch (index) {case 0:fragment = homeFragment;break;case 1:fragment = cardFragment;break;case 2:fragment = collectionFragment;break;case 3:fragment = settingFragment;break;default:break;}FragmentManager fm =getFragmentManager();// 获取Fragment管理器FragmentTransaction ft = fm.beginTransaction();ft.replace(R.id.fragmentRoot, fragment);ft.commit();}public void onCheckedChanged(RadioGroup group, int checkedId) {int selectIndex = 0;switch (checkedId) {case R.id.rbOne:selectIndex = 0;break;case R.id.rbTwo:selectIndex = 1;break;case R.id.rbThree:selectIndex = 2;break;case R.id.rbFour:selectIndex = 3;break;}showCurTab(selectIndex, checkedId, true);}private void showCurTab(int index, int checkedId, boolean isSelect) {radioGroup.check(checkedId);showFragment(index);for (int i = 0; i < radioGroup.getChildCount(); i++) {if (i == index) {changeTabImage(i, true);} else {changeTabImage(i, false);}}}private void changeTabImage(int index, boolean isSelect) {RadioButton rButton = (RadioButton) radioGroup.getChildAt(index);switch (index) {case 0:if (isSelect) {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.home_select, 0, 0);rButton.setTextColor(getResources().getColor(R.color.color_white));} else {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.home, 0, 0);rButton.setTextColor(getResources().getColor(R.color.gray_color));}break;case 1:if (isSelect) {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.card_select, 0, 0);rButton.setTextColor(getResources().getColor(R.color.color_white));} else {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.card, 0, 0);rButton.setTextColor(getResources().getColor(R.color.gray_color));}break;case 2:if (isSelect) {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.collection_select, 0, 0);rButton.setTextColor(getResources().getColor(R.color.color_white));} else {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.collection, 0, 0);rButton.setTextColor(getResources().getColor(R.color.gray_color));}break;case 3:if (isSelect) {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.me_select, 0, 0);rButton.setTextColor(getResources().getColor(R.color.color_white));} else {rButton.setCompoundDrawablesWithIntrinsicBounds(0,R.drawable.me, 0, 0);rButton.setTextColor(getResources().getColor(R.color.gray_color));}break;}}int waitTime = 2000;long touchTime = 0;@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {if(event.getAction() == KeyEvent.ACTION_DOWN && KeyEvent.KEYCODE_BACK == keyCode) {long currentTime = System.currentTimeMillis();if((currentTime-touchTime)>=waitTime) {//让Toast的显示时间和等待时间相同Toast.makeText(this, "再按一次退出", Toast.LENGTH_LONG).show();touchTime = currentTime;}else {finish();}return true;}return super.onKeyDown(keyCode, event);}}

activity_main.xml代码

<?xml version="1.0" encoding="utf-8"?>
<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:background="@color/color_white"android:orientation="vertical"tools:context=".Activity.MainActivity"><FrameLayoutandroid:id="@+id/fragmentRoot"android:layout_width="match_parent"android:layout_height="0dp"android:orientation="vertical"android:layout_weight="1"></FrameLayout><FrameLayoutandroid:id="@+id/fl_main"android:layout_width="match_parent"android:layout_height="50dp"android:background="@color/activity_title_bar_color"android:layout_alignParentBottom="true" ><RadioGroupandroid:id="@+id/bottomRg"android:layout_width="fill_parent"android:layout_height="match_parent"android:orientation="horizontal"android:paddingTop="8dp" ><RadioButtonandroid:id="@+id/rbOne"style="@style/footbar"android:layout_weight="1"android:checked="true"android:drawableTop="@drawable/home_button_select"android:text="@string/fragment_frist_page"android:textColor="@color/color_white"android:background="@android:color/transparent"android:textSize="@dimen/tab_text_size" /><RadioButtonandroid:id="@+id/rbTwo"style="@style/footbar"android:layout_weight="1"android:drawableTop="@drawable/card"android:text="@string/fragment_card_page"android:background="@android:color/transparent"android:textColor="@color/gray_color"android:textSize="@dimen/tab_text_size" /><RadioButtonandroid:id="@+id/rbThree"style="@style/footbar"android:layout_weight="1"android:drawableTop="@drawable/collection"android:text="@string/fragment_collection_page"android:background="@android:color/transparent"android:textColor="@color/gray_color"android:textSize="@dimen/tab_text_size" /><RadioButtonandroid:id="@+id/rbFour"style="@style/footbar"android:layout_weight="1"android:drawableTop="@drawable/me"android:text="@string/fragment_me_page"android:background="@android:color/transparent"android:textColor="@color/gray_color"android:textSize="@dimen/tab_text_size" /></RadioGroup></FrameLayout>
</LinearLayout>

res - -》values - -》styles.xml 文件中添加style标签

  <style name="footbar"><item name="android:layout_width">fill_parent</item><item name="android:layout_height">fill_parent</item><item name="android:textSize">10sp</item><item name="android:textColor">#FFFFFF</item> <!--白色--><item name="android:singleLine">true</item><item name="android:ellipsize">marquee</item><item name="android:button">@null</item><item name="android:gravity">bottom|center_horizontal</item><item name="android:paddingBottom">2dp</item></style>