android的Viewpager 的各種經常的用法,朋友問我要過,是以就稍微總結一下,
ViewPager + Fragment 經常用到 代碼是從 actionbarsherlock 中提取出來的,這個效果都知道是 滑動來切換的。直接上代碼了
在這裡簡單說明一下 FragmentStatePagerAdapter 和 FragmentPagerAdapter
2個adapter
第一種 fragment狀态adapter - 在目前隻會存在 前1個fragment 目前 fragment 和 下1個 fragment 其他銷毀 ,适合加載多資料
第二種 FragmentPagerAdapter - 全部存在,是以不太适合加載 大量的資料 如圖檔什麼的,很容易記憶體溢出。
工程結構:
![](https://img.laitimes.com/img/__Qf2AjLwojIjJCLyojI0JCLiAnYldHL0FWby9mZvwFN4ETMfdHLkVGepZ2XtxSZ6l2clJ3LcV2Zh1Wa9M3clN2byBXLzN3btgHL9s2RkBnVHFmb1clWvB3MaVnRtp1XlBXe0xCMy81dvRWYoNHLwEzX5xCMx8FesU2cfdGLwMzX0xiRGZkRGZ0Xy9GbvNGLpZTY1EmMZVDUSFTU4VFRR9Fd4VGdsQTMfVmepNHLrJXYtJXZ0F2dvwVZnFWbp1zczV2YvJHctM3cv1Ce-cGcq5SOwUzM3UjZ4YWNiRmNyEWNzYzXxEjNzQTM3IzLcBTMyIDMy8CXn9Gbi9CXzV2Zh1WavwVbvNmLvR3YxUjLyM3Lc9CX6MHc0RHaiojIsJye.jpg)
activity adapter 在一起 (static類型的 Fragment)
public class ViewPageFragment extends FragmentActivity {
//這個是有多少個 fragment頁面
static final int NUM_ITEMS = 5;
private MyAdapter mAdapter;
private ViewPager mPager;
private int nowPage;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.pagers_fragment_main);
mAdapter = new MyAdapter(getSupportFragmentManager() );
mPager = (ViewPager)findViewById(R.id.mypagers_pager);
mPager.setAdapter(mAdapter);
}
/**
* 有狀态的 ,隻會有前3個存在 其他銷毀, 前1個, 中間, 下一個
*/
public static class MyAdapter extends FragmentStatePagerAdapter {
public MyAdapter(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return NUM_ITEMS;
}
//得到每個item
@Override
public Fragment getItem(int position) {
return ArrayFragment.newInstance(position);
}
// 初始化每個頁卡選項
@Override
public Object instantiateItem(ViewGroup arg0, int arg1) {
// TODO Auto-generated method stub
return super.instantiateItem(arg0, arg1);
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
System.out.println( "position Destory" + position);
super.destroyItem(container, position, object);
}
}
/**
* 無狀态的 會全部加載着, 這個适合少量的 特别多的圖檔啊啥的 還是用 FragmentStatePagerAdapter
* @author lilei
*/
// public static class MyAdapter extends FragmentPagerAdapter {
// public MyAdapter(FragmentManager fm ) {
// super(fm);
//
// }
//
// @Override
// public int getCount() {
// return NUM_ITEMS;
// }
//
// @Override
// public Fragment getItem(int position) {
// // 傳回相應的 fragment
// return ArrayFragment.newInstance(position);
// }
//
// @Override
// public void destroyItem(ViewGroup container, int position, Object object) {
// System.out.println( "position Destory" + position);
// super.destroyItem(container, position, object);
// }
// }
/**
* 所有的 每個Fragment
*/
public static class ArrayFragment extends Fragment {
int mNum;
static ArrayFragment newInstance(int num) {
ArrayFragment array= new ArrayFragment();
Bundle args = new Bundle();
args.putInt("num", num);
array.setArguments(args);
return array;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mNum = getArguments() != null ? getArguments().getInt("num") : 1;
System.out.println("mNum Fragment create ="+ mNum);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
System.out.println("onCreateView = ");
//在這裡加載每個 fragment的顯示的 View
View v = null;
if(mNum == 0){
v = inflater.inflate(R.layout.pagers_fragment1, container, false);
((TextView)v.findViewById(R.id.textView1)).setText(mNum+ "= mNum");
}else if(mNum == 1){
v = inflater.inflate(R.layout.pagers_fragment1, container, false);
((TextView)v.findViewById(R.id.textView1)).setText(mNum+ "= mNum");
}else if(mNum == 2){
v = inflater.inflate(R.layout.pagers_fragment1, container, false);
((TextView)v.findViewById(R.id.textView1)).setText(mNum+ "= mNum");
}else{
v = inflater.inflate(R.layout.pagers_fragment1, container, false);
((TextView)v.findViewById(R.id.textView1)).setText(mNum+ "= mNum");
}
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
System.out.println("onActivityCreated = ");
super.onActivityCreated(savedInstanceState);
}
@Override
public void onDestroyView(){
System.out.println(mNum + "mNumDestory");
super.onDestroyView();
}
@Override
public void onDestroy(){
super.onDestroy();
}
}
}
和 1也沒什麼太大差別( 個中用處 看個人了 )
public class ViewPageFragmentCS extends FragmentActivity {
//這個是有多少個 fragment頁面
private MyAdapter mAdapter;
private ViewPager mPager;
private List<Entity> list = new ArrayList<ViewPageFragmentCS.Entity>();;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.pagers_fragment_main);
for (int i = 0; i < 7 ; i++) {
Entity ee = new Entity();
ee.name = "ll"+ i;
ee.age = ""+ i;
list.add(ee);
}
mAdapter = new MyAdapter(getSupportFragmentManager(),list);
mPager = (ViewPager)findViewById(R.id.mypagers_pager);
mPager.setAdapter(mAdapter);
}
private class Entity{
public String name;
public String age;
}
// 在這裡你可以傳 list<Fragment> 也可以傳遞 list<Object>資料
public class MyAdapter extends FragmentStatePagerAdapter {
List<Entity> list_ee;
public MyAdapter(FragmentManager fm, List<Entity> ee) {
super(fm);
this.list_ee = ee ;
}
@Override
public int getCount() {
return list_ee.size();
}
// 初始化每個頁卡選項
@Override
public Object instantiateItem(ViewGroup arg0, int position) {
ArrayFragment ff = (ArrayFragment)super.instantiateItem(arg0, position);
ff.setThings(list_ee.get(position),position);
return ff;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
System.out.println( "position Destory" + position);
super.destroyItem(container, position, object);
}
@Override
public Fragment getItem(int arg0) {
// TODO Auto-generated method stub
return new ArrayFragment();
}
}
/**
* 所有的 每個Fragment
*/
public class ArrayFragment extends Fragment {
private Entity ee;
private int position;
public void setThings(Entity ee,int position){
this.ee =ee ;
this.position = position;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
System.out.println("onCreateView = ");
//在這裡加載每個 fragment的顯示的 View
View v = inflater.inflate(R.layout.pagers_fragment1, container, false);
((TextView)v.findViewById(R.id.textView1)).setText(ee.name+ "= ee.Name -=age"+ ee.age);
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
System.out.println("onActivityCreated = ");
super.onActivityCreated(savedInstanceState);
}
@Override
public void onDestroyView(){
System.out.println("onDestroyView = "+ position);
super.onDestroyView();
}
@Override
public void onDestroy(){
System.out.println("onDestroy = "+ position);
super.onDestroy();
}
}
}
直接複制過去就可以看效果了 别忘記 V4包,xml 布局檔案 自己随便整個吧。