android实现底部导航栏

底部导航栏我选择用FragmentTabHost+Fragment来实现，这个方法比较好用，代码量也不多

首先是开始的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="${relativePackage}.${activityClass}" >
<FrameLayout
android:id="@+id/main_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="@+id/main_tab"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" >
</FrameLayout>
<view
android:id="@+id/main_tab"
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
class="android.support.v4.app.FragmentTabHost" />
</RelativeLayout>

也可以直接在xml文件里面写

<android.support.v4.view.FragmentTabHost >
</android.support.v4.view.FragmentTabHost>

这xml文件就一个view加一个tab  view用来显示碎片，tab用来放置底部按钮的数量

再来是tab_foot.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:background="#F6F6F6"
android:gravity="center"
android:orientation="vertical" >
<ImageView
android:id="@+id/foot_iv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/home1" />
<TextView
android:id="@+id/foot_tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="3dp"
android:text="首页"
android:textColor="@color/tab_color" />
</LinearLayout>

这是每个底部按钮的布局设置的xml文件

再来是MainActivity的代码

package com.gjn.mynavigation;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTabHost;
import android.view.LayoutInflater;
import android.view.View;
import android.view.Window;
import android.widget.ImageView;
import android.widget.TabWidget;
import android.widget.TextView;
import android.widget.TabHost.OnTabChangeListener;
import android.widget.TabHost.TabSpec;
public class MainActivity extends FragmentActivity implements OnTabChangeListener {
private FragmentTabHost mTabHost;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
//初始化FragmentTabHost
initHost();
//初始化底部导航栏
initTab();
//默认选中
mTabHost.onTabChanged(TabDb.getTabsTxt()[0]);
}
private void initTab() {
String[] tabs = TabDb.getTabsTxt();
for (int i = 0; i < tabs.length; i++) {
//新建TabSpec
TabSpec tabSpec = mTabHost.newTabSpec(TabDb.getTabsTxt()[i]);
//设置view
View view = LayoutInflater.from(this).inflate(R.layout.tabs_foot, null);
((TextView) view.findViewById(R.id.foot_tv)).setText(TabDb.getTabsTxt()[i]);
((ImageView) view.findViewById(R.id.foot_iv)).setImageResource(TabDb.getTabsImg()[i]);
tabSpec.setIndicator(view);
//加入TabSpec
mTabHost.addTab(tabSpec,TabDb.getFramgent()[i],null);
}
}
/***
* 初始化Host
*/
private void initHost() {
mTabHost = (FragmentTabHost) findViewById(R.id.main_tab);
//调用setup方法 设置view
mTabHost.setup(this, getSupportFragmentManager(),R.id.main_view);
//去除分割线
mTabHost.getTabWidget().setDividerDrawable(null);
//监听事件
mTabHost.setOnTabChangedListener(this);
}
@Override
public void onTabChanged(String arg0) {
//从分割线中获得多少个切换界面
TabWidget tabw = mTabHost.getTabWidget();
for (int i = 0; i < tabw.getChildCount(); i++) {
View v = tabw.getChildAt(i);
TextView tv = (TextView) v.findViewById(R.id.foot_tv);
ImageView iv = (ImageView) v.findViewById(R.id.foot_iv);
//修改当前的界面按钮颜色图片
if (i == mTabHost.getCurrentTab()) {
tv.setTextColor(getResources().getColor(R.color.tab_light_color));
iv.setImageResource(TabDb.getTabsImgLight()[i]);
}else{
tv.setTextColor(getResources().getColor(R.color.tab_color));
iv.setImageResource(TabDb.getTabsImg()[i]);
}
}
}
}

其中TabDb类是用来设置导航栏的数据和图片切换时候的资源
 以下是TabDb类

package com.gjn.mynavigation;
public class TabDb {
/***
* 获得底部所有项
*/
public static String[] getTabsTxt() {
String[] tabs = {"首页","交易","地点","我的"};
return tabs;
}
/***
* 获得所有碎片
*/
public static Class[] getFramgent(){
Class[] cls = {OneFm.class,TwoFm.class,ThreeFm.class,FourFm.class};
return cls ;
}
/***
* 获得所有点击前的图片
*/
public static int[] getTabsImg(){
int[] img = {R.drawable.home1,R.drawable.glod1,R.drawable.xc1,R.drawable.user1};
return img ;
}
/***
* 获得所有点击后的图片
*/
public static int[] getTabsImgLight(){
int[] img = {R.drawable.home2,R.drawable.glod2,R.drawable.xc2,R.drawable.user2};
return img ;
}
}

到此，底部导航栏就算是完全实现了。

现在来实现顶部导航栏，看了许多最后使用了RadioGroup+ViewPager来实现 
首先是为第一个碎片设计一个xml布局：fm_one.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" >
<HorizontalScrollView
android:id="@+id/one_hv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="none" >
<RadioGroup
android:id="@+id/one_rg"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
</RadioGroup>
</HorizontalScrollView>
<view
android:id="@+id/one_view"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
class="android.support.v4.view.ViewPager" />
</LinearLayout>

 设置顶部导航栏和显示view
 之后是导航栏的每个项的布局

 tab_rb.xml

<?xml version="1.0" encoding="utf-8"?>
<RadioButton xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/tab_rb_selector"
android:button="@null"
android:paddingBottom="10dp"
android:paddingLeft="15dp"
android:paddingRight="15dp"
android:paddingTop="10dp"
android:text="今日" >
</RadioButton>

其中设置selector文件来控制点击和未点击的状态

tab_rb_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
<!-- 点击 -->
<item android:state_checked="true">
<layer-list >
<item >
<shape android:shape="rectangle">
<stroke android:width="5dp" android:color="@color/tab_light_color"/>
</shape>
</item>
<item android:bottom="5dp">
<shape android:shape="rectangle">
<solid android:color="#fff"/>
</shape>
</item>
</layer-list>
</item>
<!-- 默认 -->
<item >
<shape >
<solid android:color="#fafafa"/>
</shape>
</item>
</selector>

 设置了点击和默认的时候的显示状态
 最后来实现OneFm类

package com.gjn.mynavigation;
import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.DisplayMetrics;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.HorizontalScrollView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.LayoutParams;
import android.widget.RadioGroup.OnCheckedChangeListener;
public class OneFm extends Fragment implements OnPageChangeListener {
private View view;
private RadioGroup rg_;
private ViewPager vp_;
private HorizontalScrollView hv_;
private List<Fragment> newsList = new ArrayList<Fragment>();
private OneFmAdapter adapter;
@Override
public View onCreateView(LayoutInflater inflater,
@Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
if (view == null) {
//初始化view
view = inflater.inflate(R.layout.fm_one, container,false);
rg_ = (RadioGroup) view.findViewById(R.id.one_rg);
vp_ = (ViewPager) view.findViewById(R.id.one_view);
hv_ = (HorizontalScrollView) view.findViewById(R.id.one_hv);
//设置RadioGroup点击事件
rg_.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int id) {
vp_.setCurrentItem(id);
}
}
//初始化顶部导航栏
initTab(inflater);
//初始化viewpager
initView();
}
/**
* 底部导航栏切换后 由于没有销毁顶部设置导致如果没有重新设置view
* 导致底部切换后切回顶部页面数据会消失等bug
* 以下设置每次重新创建view即可
*/
ViewGroup parent = (ViewGroup) view.getParent();
if (parent != null) {
parent.removeView(view);
}
return view;
}
/***
* 初始化viewpager
*/
private void initView() {
List<HTab> hTabs = HTabDb.getSelected();
for (int i = 0; i < hTabs.size(); i++) {
OneFm1 fm1 = new OneFm1();
Bundle bundle = new Bundle();
bundle.putString("name", hTabs.get(i).getName());
fm1.setArguments(bundle);
newsList.add(fm1);
}
//设置viewpager适配器
adapter = new OneFmAdapter(getActivity().getSupportFragmentManager(),newsList);
vp_.setAdapter(adapter);
//两个viewpager切换不重新加载
vp_.setOffscreenPageLimit(2);
//设置默认
vp_.setCurrentItem(0);
//设置viewpager监听事件
vp_.setOnPageChangeListener(this);
}
/***
* 初始化头部导航栏
* @param inflater
*/
private void initTab(LayoutInflater inflater) {
List<HTab> hTabs = HTabDb.getSelected();
for (int i = 0; i < hTabs.size(); i++) {
//设置头部项布局初始化数据
RadioButton rbButton = (RadioButton) inflater.inflate(R.layout.tab_rb, null);
rbButton.setId(i);
rbButton.setText(hTabs.get(i).getName());
LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT);
//加入RadioGroup
rg_.addView(rbButton,params);
}
//默认点击
rg_.check(0);
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageSelected(int id) {
setTab(id);
}
/***
* 页面跳转切换头部偏移设置
* @param id
*/
private void setTab(int id) {
RadioButton rbButton = (RadioButton) rg_.getChildAt(id);
//设置标题被点击
rbButton.setChecked(true);
//偏移设置
int left = rbButton.getLeft();
int width = rbButton.getMeasuredWidth();
DisplayMetrics metrics = new DisplayMetrics();
getActivity().getWindowManager().getDefaultDisplay().getMetrics(metrics);
int screenWidth = metrics.widthPixels;
//移动距离= 左边的位置 + button宽度的一半 - 屏幕宽度的一半
int len = left + width / 2 - screenWidth / 2;
//移动
hv_.smoothScrollTo(len, 0);
}
}

其中有两个数据类和一个碎片类

数据类

HTab.java

package com.gjn.mynavigation;
/***
* 头部Tab属性
*
*/
public class HTab {
private String name;
public HTab(String name) {
super();
this.setName(name);
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}

 HTabDb.java

package com.gjn.mynavigation;
import java.util.ArrayList;
import java.util.List;
public class HTabDb {
private static final List<HTab> Selected = new ArrayList<HTab>();
static{
Selected.add(new HTab("今日"));
Selected.add(new HTab("头条"));
Selected.add(new HTab("娱乐"));
Selected.add(new HTab("财经"));
Selected.add(new HTab("军事"));
Selected.add(new HTab("科技"));
Selected.add(new HTab("时尚"));
Selected.add(new HTab("体育"));
}
/***
* 获得头部tab的所有项
*/
public static List<HTab> getSelected() {
return Selected;
}
}

碎片类
OneFm1.java

package com.gjn.mynavigation;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class OneFm1 extends Fragment {
private String name;
@Override
public void setArguments(Bundle args) {
name = args.getString("name");
}
@Override
public View onCreateView(LayoutInflater inflater,
@Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment, container,false);
((TextView) view.findViewById(R.id.fm_text)).setText(name);
return view;
}
}

这样就把顶部的导航栏加入到了第一个fragment里面并且实现了切换功能
最后把fragment.xml贴下，就是每个碎片最默认的显示页面

<?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:gravity="center"
android:orientation="vertical" >
<TextView
android:id="@+id/fm_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>