FragmentTabHost +viewpager
这个方式 跟上面那个方式差不多 都是通过 监听 实现联动
如果只使用FragmentTabHost 只能实现 点击tab切换 页面的效果 不能实现左右滑动 而 结合viewPager 刚好实现这一效果
先来看看FragmentTabHost经常用的方法
- setup() 在使用addTab之前调用 设置必要的数据 如 FragmentManager,Fragment的容器id
- addTab() 添加标签
- newTabSpec() 新建 tab
- setCurrentTab() 设置当前显示的标签
- setOnChangeTabListtener 设置tab选中改变监听
- tabHost.getTabWidget().setDividerDrawable(null); //去除间隔线
- Tab的常用方法:
- setIndicator() 可以设置view 和 字符串main布局
<?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:id="@+id/activity_tab_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.skymxc.demo.fragment.TabPagerActivity">
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"></android.support.v4.view.ViewPager>
<android.support.v4.app.FragmentTabHost
android:id="@+id/tab_host"
android:layout_width="match_parent"
android:layout_height="wrap_content"></android.support.v4.app.FragmentTabHost>
</LinearLayout>
Framgent 简单起见 就不写布局文件了 其他的Fragment 跟这个类似
public class DiscoverFragment extends Fragment {
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
TextView textView = new TextView(getActivity());
textView.setText("发现");
textView.setGravity(Gravity.CENTER);
return textView;
}
}
tab 的布局 图片在上 文本在下 比较简单
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="@+id/icon"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_gravity="center"/>
<TextView
android:id="@+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/selector_font"
android:text="发现"
android:layout_gravity="center"/>
</LinearLayout>
selector 基本类似 这里贴一个
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_selected="true" android:drawable="@mipmap/cb_icon_discover_selected"/>
<item android:drawable="@mipmap/cb_icon_discover_normal"/>
</selector>
Java 代码
初始化 TabHost
private void initTabHost() {
tabHost.setup(this,getSupportFragmentManager(), R.id.pager);
tabHost.getTabWidget().setDividerDrawable(null);
tabHost.addTab(tabHost.newTabSpec("discover").setIndicator(createView(R.drawable.selector_bg,"发现")), DiscoverFragment.class,null);
tabHost.addTab(tabHost.newTabSpec("attach").setIndicator(createView(R.drawable.selector_bg_attach,"关注")), AttachFragment.class,null);
tabHost.addTab(tabHost.newTabSpec("message").setIndicator(createView(R.drawable.selector_bg_message,"消息")), MsgFragment.class,null);
tabHost.addTab(tabHost.newTabSpec("info").setIndicator(createView(R.drawable.selector_bg_info,"我的")), ContactFragment.class,null);
}
初始化 pager 并绑定适配器
/**
* 初始化 pager 绑定适配器
*/
private void initPager() {
fragments = new ArrayList<>();
fragments.add(new DiscoverFragment());
fragments.add(new AttachFragment());
fragments.add(new MsgFragment());
fragments.add(new ContactFragment());
FragmentAdapter adapter = new FragmentAdapter(getSupportFragmentManager(),fragments);
pager.setAdapter(adapter);
}
分别给 TabHost 和pager 添加监听 实现联动
/**
* 为TabHost和viewPager 添加监听 让其联动
*/
private void bindTabAndPager() {
tabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
/**
* tab改变后
* @param tabId 当前tab的tag
*/
@Override
public void onTabChanged(String tabId) {
log("vonTabChanged:"+tabId);
int position = tabHost.getCurrentTab();
pager.setCurrentItem(position,true);
}
});
pager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
/**
* 页面滑动 触发
* @param position 当前显得第一个页面的索引,当滑动出现时屏幕就会显示两个pager, 向右滑 position为当前-1(左边的pager就显示出来了),向左滑position为当前(右面就显出来了),
* @param positionOffset 0-1之间 position的偏移量 从原始位置的偏移量
* @param positionOffsetPixels 从position偏移的像素值 从原始位置的便宜像素
*/
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
log("onPageScrolled=============position:"+position+"====positionOffset:"+positionOffset+"====positionOffsetPixels:"+positionOffsetPixels);
}
/**
* 页面选中后
* @param position 当前页面的index
*/
@Override
public void onPageSelected(int position) {
tabHost.setCurrentTab(position);
log("onPageSelected==========:position:"+position);
}
/**
* 页面滑动状态改变时触发
* @param state 当前滑动状态 共三个状态值
*/
@Override
public void onPageScrollStateChanged(int state) {
String stateStr="";
switch (state){
case ViewPager.SCROLL_STATE_DRAGGING:
stateStr="正在拖动";
break;
case ViewPager.SCROLL_STATE_SETTLING:
stateStr="正在去往最终位置 即将到达最终位置";
break;
case ViewPager.SCROLL_STATE_IDLE:
stateStr="滑动停止,当前页面充满屏幕";
break;
}
log("onPageScrollStateChanged========stateCode:"+state+"====state:"+stateStr);
}
});
}
完整代码
public class TabPagerActivity extends AppCompatActivity {
private static final String TAG ="TabPagerActivity";
private FragmentTabHost tabHost;
private ViewPager pager;
private List<Fragment> fragments;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_tab_pager);
tabHost = (FragmentTabHost) findViewById(R.id.tab_host);
pager = (ViewPager) findViewById(R.id.pager);
//初始化TabHost
initTabHost();
//初始化pager
initPager();
//添加监听关联TabHost和viewPager
bindTabAndPager();
}
/**
* 为TabHost和viewPager 添加监听 让其联动
*/
private void bindTabAndPager() {
tabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
/**
* tab改变后
* @param tabId 当前tab的tag
*/
@Override
public void onTabChanged(String tabId) {
log("vonTabChanged:"+tabId);
int position = tabHost.getCurrentTab();
pager.setCurrentItem(position,true);
}
});
pager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
/**
* 页面滑动 触发
* @param position 当前显得第一个页面的索引,当滑动出现时屏幕就会显示两个pager, 向右滑 position为当前-1(左边的pager就显示出来了),向左滑position为当前(右面就显出来了),
* @param positionOffset 0-1之间 position的偏移量 从原始位置的偏移量
* @param positionOffsetPixels 从position偏移的像素值 从原始位置的便宜像素
*/
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
log("onPageScrolled=============position:"+position+"====positionOffset:"+positionOffset+"====positionOffsetPixels:"+positionOffsetPixels);
}
/**
* 页面选中后
* @param position 当前页面的index
*/
@Override
public void onPageSelected(int position) {
tabHost.setCurrentTab(position);
log("onPageSelected==========:position:"+position);
}
/**
* 页面滑动状态改变时触发
* @param state 当前滑动状态 共三个状态值
*/
@Override
public void onPageScrollStateChanged(int state) {
String stateStr="";
switch (state){
case ViewPager.SCROLL_STATE_DRAGGING:
stateStr="正在拖动";
break;
case ViewPager.SCROLL_STATE_SETTLING:
stateStr="正在去往最终位置 即将到达最终位置";
break;
case ViewPager.SCROLL_STATE_IDLE:
stateStr="滑动停止,当前页面充满屏幕";
break;
}
log("onPageScrollStateChanged========stateCode:"+state+"====state:"+stateStr);
}
});
}
/**
* 初始化 pager 绑定适配器
*/
private void initPager() {
fragments = new ArrayList<>();
fragments.add(new DiscoverFragment());
fragments.add(new AttachFragment());
fragments.add(new MsgFragment());
fragments.add(new ContactFragment());
FragmentAdapter adapter = new FragmentAdapter(getSupportFragmentManager(),fragments);
pager.setAdapter(adapter);
}
/**
* 初始化 TabHost
*/
private void initTabHost() {
tabHost.setup(this,getSupportFragmentManager(), R.id.pager);
tabHost.getTabWidget().setDividerDrawable(null);
tabHost.addTab(tabHost.newTabSpec("discover").setIndicator(createView(R.drawable.selector_bg,"发现")), DiscoverFragment.class,null);
tabHost.addTab(tabHost.newTabSpec("attach").setIndicator(createView(R.drawable.selector_bg_attach,"关注")), AttachFragment.class,null);
tabHost.addTab(tabHost.newTabSpec("message").setIndicator(createView(R.drawable.selector_bg_message,"消息")), MsgFragment.class,null);
tabHost.addTab(tabHost.newTabSpec("info").setIndicator(createView(R.drawable.selector_bg_info,"我的")), ContactFragment.class,null);
}
/**
* 返回view
* @param icon
* @param tab
* @return
*/
private View createView(int icon,String tab){
View view = getLayoutInflater().inflate(R.layout.fragment_tab_discover,null);
ImageView imageView = (ImageView) view.findViewById(R.id.icon);
TextView title = (TextView) view.findViewById(R.id.title);
imageView.setImageResource(icon);
title.setText(tab);
return view;
}
private void log(String log){
Log.e(TAG,"="+log+"=");
}
}