Question

我在我的应用程序中为一个库活动创建了一个GridView，并且我在活动首次启动时发现了奇怪的行为。我附上了一个打印声明，告诉我每个图像何时加载，这是我得到的输出：

01-30 17:27:09.597 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.607 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.607 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.607 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_24_07_146 into slot 1
01-30 17:27:09.707 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_24_34_369 into slot 2
01-30 17:27:09.717 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_24_38_530 into slot 3
01-30 17:27:09.717 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_24_45_214 into slot 4
01-30 17:27:09.717 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.717 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.717 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.717 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.787 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.787 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.787 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0
01-30 17:27:09.787 25390-25390/com.thomas.galleryapp I/System.out: Loaded gallery_img_2016_01_30_17_23_59_197 into slot 0

似乎无论将多少项放入GridView，项目0都会多次加载，通常在15-25次之间。为什么要继续重装第一件商品？这是GridView的xml：

<GridView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_margin="10dp"
        android:id="@+id/gridView"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:numColumns="3"
        android:horizontalSpacing="10dp"
        android:verticalSpacing="10dp"
        android:layout_centerHorizontal="true"
        android:gravity="center" />

对于网格项目：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.thomas.galleryapp.Views.SquareImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/thumbnail"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true"
        android:scaleType="centerCrop" />

    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/selectedCheckbox"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:paddingTop="10dp" />
</RelativeLayout>

我的自定义SquareImageView类：

public class SquareImageView extends ImageView {

    public SquareImageView(final Context context)
    {
        super(context);
    }

    public SquareImageView(final Context context, final AttributeSet attrs)
    {
        super(context, attrs);
    }

    public SquareImageView(final Context context, final AttributeSet attrs, final int defStyle)
    {
        super(context, attrs, defStyle);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, widthMeasureSpec);
    }
}

Grid的图像适配器：

private class ImageAdapter extends BaseAdapter{
    private LayoutInflater galleryItemInflater;

    public ImageAdapter() {
        galleryItemInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    public View getView(int position, View convertView, ViewGroup parent){
        ImageView imageView;
        if (convertView == null) {
            convertView = galleryItemInflater.inflate(R.layout.gallery_item, null);
        }
        imageView = (ImageView) convertView.findViewById(R.id.thumbnail);
        if (fileList.size() > 0){
            imageView.setImageBitmap(fileList.get(position).getImage());
            System.out.println("Loaded " + fileList.get(position).getFileName() + " into slot " + position);
        }
        return convertView;
    }

    public int getCount(){
        return fileList.size();
    }

    public Object getItem(int position) {
        return null;
    }

    public long getItemId(int position) {
        return 0;
    }
}

Gridview项目多次加载

0 个答案: