FragmentTabHost可以很好的帮我们管理fragment，使用FragmentTabHost我们根本不需要处理内存重启后Fragmen的重叠或显示错乱的问题。所以掌握其用法很有必要
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.app.FragmentTabHost
android:id="@android:id/tabhost"
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="com.ztiany.mydemo.fragments.FragmentTabHostActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<!-- 这个布局决定了标签在上面还是在下面显示 -->
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1"/>
<TabWidget
android:paddingBottom="10dp"
android:paddingTop="10dp"
android:id="@android:id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"/>
</LinearLayout>
</android.support.v4.app.FragmentTabHost>注意的地方： id必须使用android中已经定义的id
android:id/tabhostandroid:id/tabcontentandroid:id/tabs
public class FragmentTabHostActivity extends AppCompatActivity {
private FragmentTabHost mFragmentTabHost;
private TabWidget mTabWidget;
private String[] mTabNames = {
"首页",
"分类",
"购物车",
"我的"
};
private int[] mTabSrc = {
R.drawable.tab_home_selector,
R.drawable.tab_plaza_selector,
R.drawable.tab_cart_selector,
R.drawable.tab_my_selector
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fragment_tab_host);
findView();
initFragments();//这里不需要判断savedInstanceState
setTabListener();
}
private void findView() {
mFragmentTabHost = (FragmentTabHost) findViewById(android.R.id.tabhost);
mTabWidget = (TabWidget) findViewById(android.R.id.tabs);
}
private void initFragments() {
mFragmentTabHost.setup(this, getSupportFragmentManager(), android.R.id.tabcontent);
TabHost.TabSpec tabHome = mFragmentTabHost.newTabSpec("tabHome");
tabHome.setIndicator(createTabView(0));
mFragmentTabHost.addTab(tabHome, HomeFragment.class, null);
TabHost.TabSpec tabPlaza = mFragmentTabHost.newTabSpec("tabPlaza");
tabPlaza.setIndicator(createTabView(1));
mFragmentTabHost.addTab(tabPlaza, PlazaFragment.class, null);
TabHost.TabSpec tabShopping = mFragmentTabHost.newTabSpec("tabShopping");
tabShopping.setIndicator(createTabView(2));
mFragmentTabHost.addTab(tabShopping, ShoppingFragment.class, null);
TabHost.TabSpec tabMine = mFragmentTabHost.newTabSpec("tabMine");
tabMine.setIndicator(createTabView(3));
mFragmentTabHost.addTab(tabMine, MineFragment.class, null);
mFragmentTabHost.getTabWidget().setDividerDrawable(null);//去掉左右的分割线
mFragmentTabHost.getTabWidget().setStripEnabled(false);//去掉分割线
}
private void setTabListener() {
mFragmentTabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
@Override
public void onTabChanged(String tabId) {
Log.d("FragmentTabHostActivity", tabId);
}
});
}
private View createTabView(int i) {
AppCompatTextView textView = new AppCompatTextView(this);
textView.setGravity(Gravity.CENTER);
textView.setText(mTabNames[i]);
textView.setTextColor(getResources().getColorStateList(R.color.tab_color));
Drawable drawable = createDrawable(i);
textView.setCompoundDrawablesWithIntrinsicBounds(null, drawable, null, null);
return textView;
}
private Drawable createDrawable(int i) {
int drawableId = mTabSrc[i];
return getResources().getDrawable(drawableId);
}
}Fragment：
public class HomeFragment extends BaseFragment {
private AppCompatTextView mAppCompatTextView;
@Override
public void onAttach(Context context) {
debugLifeCycle();
super.onAttach(context);
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
//没必要每次都重建视图
if (mAppCompatTextView == null) {
mAppCompatTextView = new AppCompatTextView(getContext());
Log.d(tag(), "onCreateView() called with: " + "HomeFragment");
mAppCompatTextView.setText("HomeFragment");
mAppCompatTextView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
}
});
}
return mAppCompatTextView;
}
}tabColor：
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="@color/colorAccent" android:state_selected="true"/>
<item android:color="@color/colorPrimary" android:state_selected="false"/>
<item android:color="@color/colorPrimary"/>
</selector>drawable
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/tab_follow_circle_select" android:state_selected="true"/>
<item android:drawable="@drawable/tab_follow_circle_nor" android:state_selected="false"/>
<item android:drawable="@drawable/tab_follow_circle_nor"/>
</selector>
进入界面
HomeFragment-->onAttach
HomeFragment-->onCreate
onCreateView() called with: HomeFragment
HomeFragment-->onViewCreated
HomeFragment-->onActivityCreated
HomeFragment-->onStart
HomeFragment-->onResume
到第二个界面
PlazaFragment-->onAttach
PlazaFragment-->onCreate
HomeFragment-->onPause
HomeFragment-->onStop
HomeFragment-->onDestroyView
onCreateView() called with: PlazaFragment
PlazaFragment-->onViewCreated
PlazaFragment-->onActivityCreated
PlazaFragment-->onStart
PlazaFragment-->onResume
回到第一个界面
PlazaFragment-->onPause
PlazaFragment-->onStop
PlazaFragment-->onDestroyView
onCreateView() called with: HomeFragment
HomeFragment-->onViewCreated
HomeFragment-->onActivityCreated
HomeFragment-->onStart
HomeFragment-->onResume
在第一个界面中进入其他Activity
HomeFragment-->onPause
HomeFragment-->onStop
从其他Activity回调第一个界面
HomeFragment-->onStart
HomeFragment-->onResume
退出当前界面
HomeFragment-->onPause
HomeFragment-->onStop
HomeFragment-->onDestroyView
HomeFragment-->onDestroy
HomeFragment-->onDetach
PlazaFragment-->onDestroy
PlazaFragment-->onDetach
从生命周期的回调可以看出FragmentTabHost使用的是attach和detach来管理Fragment的。个人觉得这种方式比show+hide更加灵活。