Question

我有一个网格视图，在适配器中加载了6个单元格。当我点击每个单元格时，我将通过拍照或从图库中选择图像来添加图像。在选择图像后，网格视图仅显示为空。虽然我在一个单元格中设置图像，但是当转到另一个单元格时，之前的选择已经消失。如何完成它？请求帮助我。如果我有什么不对的地方，请指导我。

    if (convertView == null) {
        grid = new View(mContext);
        grid = inflater.inflate(R.layout.fpc_document_view, null);
        TextView textView = (TextView) grid.findViewById(R.id.grid_text);
        imageView = (ImageView) grid.findViewById(R.id.grid_image);
        if (fileList.size() == 0) {
            textView.setText(DOCUMENT_NAME_LIST[position].toString());
            for (int i = 0; i <= 6; i++) {
                imageView.setImageResource(R.mipmap.ic_add_document);
            }
        } else {

            Bitmap bitmapResized = null;
            for (int i = 0; i < fileList.size(); i++) {
                if (!fileList.get(i).equals("")) {
                    System.out.println("fileList here ,,,," + fileList.get(i).toString());
                    Drawable drawable = mContext.getResources().getDrawable(R.mipmap.ic_add_document);
                    bitmapResized = ((BitmapDrawable) drawable).getBitmap();
                } else {
                    Uri selectedImageUri = Uri.fromFile(fileList.get(i));
                    bitmapResized = ImageRelatedStuff.convertURIToBitmap(selectedImageUri, mContext);

                    if (bitmapResized != null) {
                        Bitmap bitmapTemp = bitmapResized;
                        bitmapResized = null;
                        bitmapResized = ImageRelatedStuff.getResizedBitmap(bitmapTemp, 500, 500, 0);
                    }
                }
                imageView.setImageBitmap(ImageRelatedStuff.getRoundedCornerBitmap(bitmapResized, 15));
            }
        }
    } else {
        grid = convertView;
        imageView = (ImageView) grid.findViewById(R.id.grid_image);

    }

Answer 1

更改您的代码：

if (convertView == null) {
    grid = new View(mContext);
    grid = inflater.inflate(R.layout.fpc_document_view, null);
    TextView textView = (TextView) grid.findViewById(R.id.grid_text);
    imageView = (ImageView) grid.findViewById(R.id.grid_image);
} else {
    grid = convertView;
    imageView = (ImageView) grid.findViewById(R.id.grid_image);

}
if (fileList.size() == 0) {
        textView.setText(DOCUMENT_NAME_LIST[position].toString());
        for (int i = 0; i <= 6; i++) {
            imageView.setImageResource(R.mipmap.ic_add_document);
        }
    } else {

        Bitmap bitmapResized = null;
        for (int i = 0; i < fileList.size(); i++) {
            if (!fileList.get(i).equals("")) {
                System.out.println("fileList here ,,,," + fileList.get(i).toString());
                Drawable drawable = mContext.getResources().getDrawable(R.mipmap.ic_add_document);
                bitmapResized = ((BitmapDrawable) drawable).getBitmap();
            } else {
                Uri selectedImageUri = Uri.fromFile(fileList.get(i));
                bitmapResized = ImageRelatedStuff.convertURIToBitmap(selectedImageUri, mContext);

                if (bitmapResized != null) {
                    Bitmap bitmapTemp = bitmapResized;
                    bitmapResized = null;
                    bitmapResized = ImageRelatedStuff.getResizedBitmap(bitmapTemp, 500, 500, 0);
                }
            }
            imageView.setImageBitmap(ImageRelatedStuff.getRoundedCornerBitmap(bitmapResized, 15));
        }
    }

问题是当你的convertView不等于null时，你没有在imageView上设置任何图像。这就是为什么在convertView为null的第二个单元格中，你在前一个非空的单元格上获得图像，你什么也得不到。

Answer 2

public class MyAdapter extends BaseAdapter{

private final int GRID_COUNT = 6;

// you need an array save bitmap with position
Bitmap[] bitmapArray;

public MyAdapter(){
    bitmapArray = new Bitmap[GRID_COUNT];
}

@Override
public int getCount() {
    return 6;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    if (convertView == null){
        // inflater your layout
    }
    ImageView imageView = (ImageView) convertView.findViewById(R.id.grid_image);
    // get the bitmap in array by position
    Bitmap bitmap = bitmapArray[position];
    // when bitmap is null ,show default picture
    if (bitmap == null){
        imageView.setBackgroundResource(R.drawable.ic_default);
    }else{
        imageView.setImageBitmap(bitmap);
    }
    return convertView;
}

// activity or fragment use this method call adapter refresh
public void setBitmap(int position, Bitmap bitmap){
    bitmapArray[position] = bitmap;
    notifyDataSetChanged();
}
}

更新我的回答，希望能帮到你

在gridview android中自定义适配器刷新

2 个答案: