使用ViewPager和Fragment实现滑动导航

ViewPage是android-support-v4.jar包提供的用于页面滑动的库,android-support-v4.jar是google推荐使用的一个类库,在项目中使用之前,你必须其添加到项目中(项目点右键Build path->configure build path,然后找到jar进行添加)

1.在xml布局文件中添加android.support.v4.view.ViewPager容器及显示导航所用标签android.support.v4.view.PagerTitleStrip,如我添加的xml内容如下

 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
<android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >
 
    <!--
    This title strip will display the currently visible page title, as well as the page
    titles for adjacent pages.
    -->
 
    <android.support.v4.view.PagerTitleStrip
        android:id="@+id/pager_title_strip"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="top"
        android:background="#33b5e5"
        android:paddingBottom="4dp"
        android:paddingTop="4dp"
        android:textColor="#fff" />
 
</android.support.v4.view.ViewPager>

 

2.在activity中导入以下包 

1
2
3
4
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;

3.声明变量

1
2
SectionsPagerAdapter mSectionsPagerAdapter;
ViewPager mViewPager;

 

4.在onCreate中对其进行初始化 

1
2
3
4
5
6
mSectionsPagerAdapter = new SectionsPagerAdapter(
                getSupportFragmentManager());
 
// Set up the ViewPager with the sections adapter.
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);

5.添加类SectionsPagerAdapter,我这里使用了3个标签 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
public class SectionsPagerAdapter extends FragmentPagerAdapter {
 
        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }
 
        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a DummySectionFragment (defined as a static inner class
            // below) with the page number as its lone argument.
            Fragment fragment = new HjFragment();
            Bundle args = new Bundle();
            args.putInt("no", position + 1);
            fragment.setArguments(args);
 
            return fragment;
        }
 
        @Override
        public int getCount() {
            // Show 3 total pages.
            return 3;
        }
 
        @Override
        public CharSequence getPageTitle(int position) {
            switch (position) {
            case 0:
                return "标签1";
            case 1:
                return "标签2";
            case 2:
                return "标签3";
            }
            return null;
        }
    }

可以看到在getItem中返回了一个Fragment,这个就是当滑动到不同标签时显示在ViewPager中的内容,Fragment相当于一个Activity,在可以其中的onCreateView函数中构造需要显示的内容并返回

比如,以下代码将显示一个文本信息

1
2
3
4
5
6
7
8
9
10
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    TextView textView = new TextView(getActivity());
    textView.setGravity(Gravity.CENTER);
    textView.setText("你选择了标签:"+Integer.toString(getArguments().getInt(
            "no")));
    return textView;
 
}
posted @ 2015-06-23 17:40  Bonker  阅读(399)  评论(0编辑  收藏  举报