ViewPager+FragmentTabHost

普通的ViewPager的使用

使用方法参考listview1.在布局中使用support.v4包下的viewpager控件    <android.support.v4.view.ViewPager        android:id="@+id/vp"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1">    </android.support.v4.view.ViewPager>vp = (ViewPager) findViewById(R.id.vp);     2.创建PagerAdapter的子类必须实现如下四个方法public class MyPagerAdapter extends PagerAdapter {    List<View>datas;    public MyPagerAdapter(List<View> datas) {        this.datas = datas;    }    @Override    public int getCount() {        return datas.size();    }    //通过该方法开确定要展示哪个view    @Override    public boolean isViewFromObject(View view, Object object) {        return view==object;    }    @Override    public Object instantiateItem(ViewGroup container, int position) {        View view = datas.get(position);        container.addView(view);        //这个view就是isViewFromObject中的第二个参数        return view;    }    @Override    public void destroyItem(ViewGroup container, int position, Object object) {        container.removeView(datas.get(position));    }}3.展示数据//调用vp.setadapter方法展示vp.setadater(adapter);

FragmentViewPager的使用

需要先介绍一下fragmentadapter有两种,分别是FragmentStatePagerAdapter和FragmentPagerAdapter;FragmentStatePagerAdapter 和前面的 FragmentPagerAdapter 一样，是继承子 PagerAdapter。但是，和 FragmentPagerAdapter 不一样的是，正如其类名中的 'State' 所表明的含义一样，该 PagerAdapter 的实现将只保留当前页面，当页面离开视线后，就会被消除，释放其资源;简单的说就是fragment被隐藏后FragmentStatePagerAdapter 会调用fragment的destroy方法,而FragmentPagerAdapter不会;前者适合有大量大framgent中使用;

//也可以改成继承于FragmentPagerAdapter public class MyFragmentPagerAdapter extends FragmentStatePagerAdapter {    List<Fragment> mDatas;    //相比于pageradapter,不需要实现instantiateItem()destroyItem()    public MyFragmentPagerAdapter(FragmentManager fm,List<Fragment> datas) {        super(fm);        mDatas=datas;    }    @Override    public int getCount() {        return mDatas.size();    }    @Override    public Fragment getItem(int position) {        return mDatas.get(position);    }}

设置监听器

viewPager.setAdapter(new MyViewPagerAdapter(views));//设置当前打开的页面是第几个viewPager.setCurrentItem(0);viewPager.setOnPageChangeListener(new MyOnPageChangeListener());//设置页面切换的监听

设置viewpager的切换动画效果

1.谷歌的demopublic class DepthPageTransformer implements ViewPager.PageTransformer {  private static final float MIN_SCALE = 0.75f;  public void transformPage(View view, float position) {      int pageWidth = view.getWidth();      if (position < -1) { // [-Infinity,-1)          // This page is way off-screen to the left.          view.setAlpha(0);      } else if (position <= 0) { // [-1,0]          // Use the default slide transition when moving to the left page          view.setAlpha(1);          view.setTranslationX(0);          view.setScaleX(1);          view.setScaleY(1);      } else if (position <= 1) { // (0,1]          // Fade the page out.          view.setAlpha(1 - position);          // Counteract the default slide transition          view.setTranslationX(pageWidth * -position);          // Scale the page down (between MIN_SCALE and 1)          float scaleFactor = MIN_SCALE                  + (1 - MIN_SCALE) * (1 - Math.abs(position));          view.setScaleX(scaleFactor);          view.setScaleY(scaleFactor);      } else { // (1,+Infinity]          // This page is way off-screen to the right.          view.setAlpha(0);      }  }}2.//第一个参数为false表示当进入和退出动画重叠时,能同时显示,不会被遮盖vp.setPageTransformer(true,new Translate());

FragmentTabHost的使用

布局<LinearLayout    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"    android:orientation="vertical"    tools:context="com.junx.tabhost.MainActivity">    <FrameLayout    //用于显示fragment        android:id="@+id/fl"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"        android:background="#F00"    >    </FrameLayout>    //底部导航栏    <android.support.v4.app.FragmentTabHost        android:id="@+id/tab_frag"        android:layout_width="match_parent"        android:layout_height="100dp">    </android.support.v4.app.FragmentTabHost></LinearLayout>

代码:    String tabs[] = new String[]{"哈哈1", "哈哈2", "哈哈3"};    Class classes[]={ItemFragment1.class,ItemFragment2.class,ItemFragment3.class};    private void show() {        //将tab和展示不同fragment的fl绑定        tab_frag.setup(this,getSupportFragmentManager(),R.id.fl);        //去掉导航栏间的分割线        tab_frag.getTabWidget().setDividerDrawable(null);        for (int i = 0; i < tabs.length; i++) {            TabHost.TabSpec tabSpec = tab_frag.newTabSpec(tabs[i]);            tabSpec.setIndicator(getView(i));            tab_frag.addTab(tabSpec,classes[i],null);        }    }    //返回tab中item的布局的inflated    public View getView(int i) {        View inflate = View.inflate(this,R.layout.tab_item, null);        ImageView view = inflate.findViewById(R.id.tab_imageview);        view.setBackgroundResource(R.drawable.timg);        TextView tv = inflate.findViewById(R.id.tab_textview);        tv.setText(tabs[i]);        return inflate;    }

ViewPager+FragmentTabHost

1.布局,在页面的下方放置tab    <android.support.v4.app.FragmentTabHost        android:id="@+id/tab_host"        android:layout_width="match_parent" android:layout_height="100dp">    </android.support.v4.app.FragmentTabHost>代码中:tab_host = (FragmentTabHost) findViewById(R.id.tab_host);2.将tab和viewpager绑定tab_host.setup(this,getSupportFragmentManager(),R.id.vp);    //vp的监听实现    tab_host.setOnTabChangedListener(this);    @Override    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {    }    @Override    public void onPageSelected(int position) {        tab_host.setCurrentTab(position);    }    @Override    public void onPageScrollStateChanged(int state) {    }    //tab的变化监听    @Override    public void onTabChanged(String tabId) {    //修改选中的tab的position        int position = tab_host.getCurrentTab();        vp.setCurrentItem(position);    }3.为tab填充内容        for (int i = 0; i < mFragments.size(); i++) {        //设置文字提示            TabHost.TabSpec tabSpec = tab_host.newTabSpec("??");        //设置图片view,该view中的imageview的src不能为selector,否则报错原因名不明                tabSpec.setIndicator(getTab(i));        //绑定fragment,记得要调用三个参数的addTab()            tab_host.addTab(tabSpec,mFragments.get(i).getClass(),null);        }//tab_host.setOnTabChangedListener(this);    @Override    public void onTabChanged(String tabId) {    //获取当前点击的tab的id        int position = tab_host.getCurrentTab();        vp.setCurrentItem(position);    }

FragmentTabHost自定义导航栏布局