实现ViewPager以显示来自服务器的图像

时间:2015-08-22 10:27:14

标签: android json layout android-viewpager

我想实现viewpager。在我的视图分页器中,我需要显示来自Rest API的图像。请给我必要的建议和建议,以便我能够成功。

1 个答案:

答案 0 :(得分:1)

首先,您需要一个自定义viewpager适配器: 毕加索是一个很棒的图书馆来加载图像。如果您需要进一步的帮助,我会给您一个链接:http://square.github.io/picasso/

public class ViewPagerAdapter extends PagerAdapter {
Context c;
private List<String> _imagePaths;
private LayoutInflater inflater;

public ViewPagerAdapter(Context c, List<String> imagePaths) {
    this._imagePaths = imagePaths;
    this.c = c;
}

@Override
public int getCount() {
    return this._imagePaths.size();
}

@Override
public boolean isViewFromObject(View view, Object object) {
    return view == (object);
}

@Override
public Object instantiateItem(ViewGroup container, int position) {
    ImageView imgDisplay;

    inflater = (LayoutInflater) c
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View viewLayout = inflater.inflate(R.layout.pager_item, container,
            false);

    imgDisplay = (ImageView) viewLayout.findViewById(R.id.image);

    Picasso.with(c).load(_imagePaths.get(position)).into(imgDisplay);
    (container).addView(viewLayout);

    return viewLayout;
}

@Override
public void destroyItem(ViewGroup container, int position, Object object) {
    (container).removeView((RelativeLayout) object);

}
}

这是pager_item.xml:

    <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/image"
        android:layout_centerInParent="true"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</RelativeLayout>

来自您的活动:

从Rest获取列表网址后:这就是你所做的:

List<String> urls;

public class MainPage extends Activity {
 public void onCreate(Bundle savedInstance) {
    super.onCreate(savedInstance);
    setContentView(R.layout.main_page);
urls= new ArrayList<>();
    pager = (ViewPager) findViewById(R.id.pager);
urls.add("www.image1.com");
urls.add("www.image2.com");
        pager.setAdapter(new ViewPagerAdapter(getApplicationContext(), urls));

}
}