以全长的方式截取RecyclerView的屏幕截图

Question

我想获得活动的"整页"截图.该视图包含一个包含许多项目的RecyclerView.

我可以使用此功能截取当前视图的屏幕截图:

public Bitmap getScreenBitmap() {
    View v= findViewById(R.id.container).getRootView();
    v.setDrawingCacheEnabled(true);
    v.buildDrawingCache(true);
    Bitmap b = Bitmap.createBitmap(v.getDrawingCache());
    v.setDrawingCacheEnabled(false); // clear drawing cache
    return b;
}

但它只包含我可以正常查看的项目(如预期的那样).

当我拍摄截图时,有什么方法可以让RecyclerView神奇地显示全长(一次显示所有项目)吗？

如果没有,我该如何处理这个问题？

Answer 1

灵感来自Yoav的回答.此代码适用于recyclerview项目类型,可能与其大小无关.

它通过具有linearlayout管理器和三种项目类型的recyclerview进行了测试.然而,与其他布局经理检查.

public Bitmap getScreenshotFromRecyclerView(RecyclerView view) {
        RecyclerView.Adapter adapter = view.getAdapter();
        Bitmap bigBitmap = null;
        if (adapter != null) {
            int size = adapter.getItemCount();
            int height = 0;
            Paint paint = new Paint();
            int iHeight = 0;
            final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);

            // Use 1/8th of the available memory for this memory cache.
            final int cacheSize = maxMemory / 8;
            LruCache<String, Bitmap> bitmaCache = new LruCache<>(cacheSize);
            for (int i = 0; i < size; i++) {
                RecyclerView.ViewHolder holder = adapter.createViewHolder(view, adapter.getItemViewType(i));
                adapter.onBindViewHolder(holder, i);
                holder.itemView.measure(View.MeasureSpec.makeMeasureSpec(view.getWidth(), View.MeasureSpec.EXACTLY),
                        View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
                holder.itemView.layout(0, 0, holder.itemView.getMeasuredWidth(), holder.itemView.getMeasuredHeight());
                holder.itemView.setDrawingCacheEnabled(true);
                holder.itemView.buildDrawingCache();
                Bitmap drawingCache = holder.itemView.getDrawingCache();
                if (drawingCache != null) {

                    bitmaCache.put(String.valueOf(i), drawingCache);
                }
//                holder.itemView.setDrawingCacheEnabled(false);
//                holder.itemView.destroyDrawingCache();
                height += holder.itemView.getMeasuredHeight();
            }

            bigBitmap = Bitmap.createBitmap(view.getMeasuredWidth(), height, Bitmap.Config.ARGB_8888);
            Canvas bigCanvas = new Canvas(bigBitmap);
            bigCanvas.drawColor(Color.WHITE);

            for (int i = 0; i < size; i++) {
                Bitmap bitmap = bitmaCache.get(String.valueOf(i));
                bigCanvas.drawBitmap(bitmap, 0f, iHeight, paint);
                iHeight += bitmap.getHeight();
                bitmap.recycle();
            }

        }
        return bigBitmap;
    }

Answer 2

这是我的解决方案,LinearLayoutManager当所有项目都在相同的大小,并且只有一种类型的项目.此解决方案基于此答案.

注意:它可能导致内存不足错误.

public static Bitmap getRecyclerViewScreenshot(RecyclerView view) {
        int size = view.getAdapter().getItemCount();
        RecyclerView.ViewHolder holder = view.getAdapter().createViewHolder(view, 0);
        view.getAdapter().onBindViewHolder(holder, 0);
        holder.itemView.measure(View.MeasureSpec.makeMeasureSpec(view.getWidth(), View.MeasureSpec.EXACTLY),
                View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
        holder.itemView.layout(0, 0, holder.itemView.getMeasuredWidth(), holder.itemView.getMeasuredHeight());
        Bitmap bigBitmap = Bitmap.createBitmap(view.getMeasuredWidth(), holder.itemView.getMeasuredHeight() * size,
                Bitmap.Config.ARGB_8888);
        Canvas bigCanvas = new Canvas(bigBitmap);
        bigCanvas.drawColor(Color.WHITE);
        Paint paint = new Paint();
        int iHeight = 0;
        holder.itemView.setDrawingCacheEnabled(true);
        holder.itemView.buildDrawingCache();
        bigCanvas.drawBitmap(holder.itemView.getDrawingCache(), 0f, iHeight, paint);
        holder.itemView.setDrawingCacheEnabled(false);
        holder.itemView.destroyDrawingCache();
        iHeight += holder.itemView.getMeasuredHeight();
        for (int i = 1; i < size; i++) {
            view.getAdapter().onBindViewHolder(holder, i);
            holder.itemView.setDrawingCacheEnabled(true);
            holder.itemView.buildDrawingCache();
            bigCanvas.drawBitmap(holder.itemView.getDrawingCache(), 0f, iHeight, paint);
            iHeight += holder.itemView.getMeasuredHeight();
            holder.itemView.setDrawingCacheEnabled(false);
            holder.itemView.destroyDrawingCache();
        }
        return bigBitmap;
    }

注2:它最初是用Kotlin编写的.这是我使用的原始代码.

Answer 3

无论其项目和项目类型如何，获取完整 Recyclerview 的屏幕截图：

这段代码就像一个魅力。

这是一种简洁而精确的方法：

recyclerView.measure(
        View.MeasureSpec.makeMeasureSpec(recyclerView.getWidth(), View.MeasureSpec.EXACTLY),
        View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));

Bitmap bm = Bitmap.createBitmap(recyclerView.getWidth(), recyclerView.getMeasuredHeight(), Bitmap.Config.ARGB_8888);
recyclerView.draw(new Canvas(bm));

saveImage(bm);
ImageView im
          = new ImageView(getActivity());
im.setImageBitmap(bm);
 new AlertDialog.Builder(getActivity()).setView(im).show();