結合Tab,ViewPager,Fragment實現簡單分頁滑動
阿新 • • 發佈:2019-01-04
在APP設計當中,使用ViewPager和Fragment來實現分頁滑動並不少見,該設計可以利用少量的空間來實現多內容的展示。效果圖如下:
以下是實現該功能的程式碼:
MainActivity
public class MainActivity extends AppCompatActivity {
private ViewPager viewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}
//tab點選事件
private ActionBar.TabListener mListener = new ActionBar.TabListener() {
@Override
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction ft) {
if (viewPager != null) {
viewPager.setCurrentItem(tab.getPosition()); //設定當前顯示的fragment
}
}
@Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction ft) {
}
@Override
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction ft) {
}
};
private void initView() {
final ActionBar actionBar = getSupportActionBar();
ActionBar.Tab tab1 = actionBar.newTab(); //新建tab
ActionBar.Tab tab2 = actionBar.newTab();
tab1.setText("Tab1");
tab2.setText("Tab2");
tab1.setTabListener(mListener); //設定tab監聽事件,必須在actionBar.addTab語句之前,否則報錯
tab2.setTabListener(mListener);
actionBar.addTab(tab1);
actionBar.addTab(tab2);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);//設定模式
viewPager = (ViewPager) findViewById(R.id.viewPager);
ArrayList<Fragment> fragments = new ArrayList<>(2); //新增兩個fragment或者更多
MyFragment fragment1 = new MyFragment(R.layout.fragment_tab1);
MyFragment fragment2 = new MyFragment(R.layout.fragment_tab2);
fragments.add(fragment1);
fragments.add(fragment2);
viewPager.setAdapter(new FragmentAdapter(getSupportFragmentManager(), fragments)); //設定介面卡
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() { //頁面滑動後tab跟著移動
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position); //設定當前tab選中的位置
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
}
}
MyFragement
public class MyFragment extends Fragment {
private int resource; //需要解析的佈局資源
public MyFragment(int resource) {
this.resource = resource;
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(resource, container, false); //解析佈局,此處第三個引數應為false,否則會返回父檢視的佈局,導致OOM
return v;
}
}
FragmentAdapter
//介面卡,與ListView等所需介面卡的設定類似
public class FragmentAdapter extends FragmentPagerAdapter {
private ArrayList<Fragment> fragments;
public FragmentAdapter(FragmentManager fm, ArrayList<Fragment> fragments) {
super(fm);
this.fragments = fragments;
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getCount() {
return fragments.size();
}
}
至於XML的實現相對簡單:
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<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="com.viewpager.MainActivity">
<android.support.v4.view.ViewPager
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/viewPager"
>
</android.support.v4.view.ViewPager>
</RelativeLayout>