Android-GridView 中带复选框的项目选择

Question

我遇到了 Android GridView 的问题。我已经尝试了 Whosebug 的各种解决方案，但 none 确实有效。

我在 ArrayAdapter 的帮助下填充 GridView。适配器扩充仅包含图像和复选框的布局。我正在使用 "convertView" 来防止添加图像时出现闪烁（将近 500 张图像添加到 GridView）。

问题：当我选中复选框并滚动时，选中状态消失了。此外，例如，当我选中多个 GridView 项目的复选框时，选择模式会无休止地继续所有以下元素。

我的 GridView 是 RelativeLayout 的子元素。 RelativeLayout 用作 ViewPager 中使用的片段的根元素：

<GridView
    android:id="@+id/MainGrid"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/appBackgroundColor"
    android:drawSelectorOnTop="false"
    android:listSelector="#00000000"
    android:numColumns="2"
    android:paddingLeft="6dp"
    android:paddingTop="5dp"
    android:paddingRight="6dp"
    android:translationZ="2dp" />

我正在线程的帮助下填充 GridView，该线程正在从网站下载图像数据。我认为这应该没有问题，但为了完整起见，这里是代码：

//Declaring the Array
ArrayList<GridImage> ImageArray = new ArrayList<>();

//And the adapter
Adapter_GridAdapter GridViewAdapter = new Adapter_GridAdapter (getActivity().getApplicationContext(), ImageArray );

//The following is executed 500 times in a thread
ImageArray.add(new GridImage(URL));
getActivity().runOnUiThread(new Runnable() {
    @Override
    public void run() {
        GridViewAdapter.notifyDataSetChanged();
    }
});

GridView适配器的代码：

public class Adapter_GridAdapter extends ArrayAdapter<GridImage> {

Context context;

public Adapter_GridAdapter (Context context, ArrayList<GridImage> SearchResults) {
    super(context, 0, SearchResults);
    this.context = context;
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    LayoutInflater inflater = LayoutInflater.from(getContext());
    View view = convertView;
    if (convertView == null) {
        view = inflater.inflate(R.layout.griditem_ig_post, null);

        final ImageView ThisViewIMG = view.findViewById(R.id.GridImageView);

        //Calculating Image Height (Square Image)
        ThisViewIMG.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
            @Override
            public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
                ThisViewIMG.removeOnLayoutChangeListener(this);
                ThisViewIMG.getLayoutParams().height = ThisViewIMG.getWidth();
                ThisViewIMG.requestLayout();
            }
        });

    }

    final GridImage ThisImg = getItem(position);
    final ImageView ThumbnailImage = view.findViewById(R.id.GridImageView);

    //THIS IS THE CUSTOM CHECKBOX!
    final CustomCheckBox scb = (CustomCheckBox) view.findViewById(R.id.MyCheckBox);

    //I AM SAVING THE VALUE IN THE OBJECT (TRY #38181 THAT DIDN'T WORK)
    scb.setChecked(ThisImg.IsChecked);
    scb.setOnCheckedChangeListener(new CustomCheckBox.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CustomCheckBox checkBox, boolean isChecked) {
            Log.d("CustomCheckBox", String.valueOf(isChecked));
            ThisImg.setChecked(isChecked);
        }
    });
Glide.with(context).load(Post.IMG_ThumbnailURL).fitCenter().into(ThumbnailImage);


    return view;
}
}

对象本身很简单，问题（我认为）也不应该隐藏在这里：

public class GridImage{
    public String PostURL;
    public Boolean IsChecked = false;

    GridImage(String URL){
        PostURL = URL;
    }

    public void setChecked(Boolean checked) {
        IsChecked = checked;
    }
}

我已经尝试过的：

- 我的解决方案是使用标签而不是直接保存到对象中，对吗？
- SparseBooleanArray，但我不是 100% 确定我这样做是正确的

Answer 1

在使用 ListView/GridView 适配器时，我总是避免使用 final 和 onCheckedChangeListener 因为有时两者都可能有问题逻辑似乎是正确的，所以试试下面的代码：

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    LayoutInflater inflater = LayoutInflater.from(getContext());
    View view = convertView;
    if (convertView == null) {
        view = inflater.inflate(R.layout.griditem_ig_post, null);

        ImageView ThisViewIMG = view.findViewById(R.id.GridImageView);

        //Calculating Image Height (Square Image)
        ThisViewIMG.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
            @Override
            public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
                v.removeOnLayoutChangeListener(this);
                v.getLayoutParams().height = v.getWidth();
                v.requestLayout();
            }
        });

    }

    GridImage ThisImg = getItem(position);
    ImageView ThumbnailImage = view.findViewById(R.id.GridImageView);

    //THIS IS THE CUSTOM CHECKBOX!
    CustomCheckBox scb = (CustomCheckBox) view.findViewById(R.id.MyCheckBox);

    scb.setChecked(ThisImg.IsChecked);
    scb.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            CustomCheckBox cb = (CustomCheckBox)view;
            int position = (int)cb.getTag();
            GridImage ThisImg = getItem(position);
            Log.d("CustomCheckBox", String.valueOf(!ThisImg.IsChecked));
            ThisImg.setChecked(!ThisImg.IsChecked);
            cb.setChecked(ThisImg.IsChecked);
        }
    });
    Glide.with(context).load(Post.IMG_ThumbnailURL).fitCenter().into(ThumbnailImage);

    scb.setTag(position);
    return view;
}

希望对您有所帮助！

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