Question

我尝试将Picasso与我的适配器一起使用时出现此错误。我使用Picasso是因为我在手机上出现了内存错误，而它在平板电脑上运行正常。

我以错误的方式使用毕加索吗？因为我没有看到任何错误。

更新这就是我编辑的内容

ImageView imgButtons;
        imgButtons = (ImageView) findViewById(R.id.items); 
       Picasso.with(context).load(flag[position]).fit().into(imgButtons);
        // Add viewpager_item.xml to ViewPager
        ((ViewPager) container).addView(imgButtons);

        return imgButtons;

我获得目标不能为空这是代码：

public class ViewPagerAdapter extends PagerAdapter {
    // Declare Variables
    Context context;
    int[] flag;
    String[] rank;
    LayoutInflater inflater;

    public ViewPagerAdapter(Context context,  int[] flag, String[] rank) {
        this.context = context;
        this.flag = flag;
        this.rank = rank;
    }

    @Override
    public int getCount() {
        return rank.length;
    }

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

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

        inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View itemView = inflater.inflate(R.layout.app3x, container, false);

        // Locate the ImageView in viewpager_item.xml   
        // imgflag = (ImageView) itemView.findViewById(R.id.items);

        // Capture position and set to the ImageView
        // imgflag.setImageResource(flag[position]);
        Picasso.with(context).load(flag[position]).fit().into((Target) itemView);
        // Add viewpager_item.xml to ViewPager
        ((ViewPager) container).addView(itemView);

        return itemView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        // Remove viewpager_item.xml from ViewPager
        ((ViewPager) container).removeView((RelativeLayout) object);
    }
}

我的XML：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center"
    android:orientation="vertical"
    android:background="@color/White">

    <ImageView
        android:id="@+id/items"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_alignParentRight="true"
        android:background="@color/White"
        android:scaleType="fitXY" />

</RelativeLayout>

Answer 1

来自Picasso的官方网站，其中一种正确的语法是：

Picasso.with(context).load(R.drawable.landing_screen).into(imageView1);

假设flag[]包含图像的资源ID，代码存在问题，

Picasso.with(context).load(flag[position]).fit().into((Target) itemView);

itemView是RelativeLayout，而不是ImageView。

尝试此操作（更改以评论表示）

@Override
public Object instantiateItem(ViewGroup container, int position) {
    inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View itemView = inflater.inflate(R.layout.app3x, container, false);
    ImageView imgflag = (ImageView) itemView.findViewById(R.id.items); // need this ImageView

    Picasso.with(context).load(flag[position]).fit().into(imgflag); // use ImageView

    ((ViewPager) container).addView(itemView);
    return itemView;
}

类强制转换异常：不能将RelativeLayout强制转换为com.a.a.ba

1 个答案: