Android 工具类 —— 截屏

雨点打透心脏的1/2处 2022-04-25 03:18 421阅读 0赞

Android 8.0 截屏

/**
     * 快照工具
     */
    public class SnapShotUtil {
    
        /**
         * 获取屏幕截图。
         */
        public static Bitmap getScreen(Activity activity) {
            View view = activity.getWindow().getDecorView();
            //启用绘制缓存
            view.setDrawingCacheEnabled(true);
            //构建缓存视图
            view.buildDrawingCache();
            //获得视图的缓存图像
            Bitmap cache = view.getDrawingCache();
            //状态栏区只有背景色，却截取不到任何文字，因此要手动裁剪掉
            Rect activityRect = new Rect();
            //获取当前activity的可见区域
            view.getWindowVisibleDisplayFrame(activityRect);
            Bitmap bitmap = BitmapUtil.crop(cache, activityRect);
            //关闭视图缓存机制
            view.setDrawingCacheEnabled(false);
            //删除视图缓存
            view.destroyDrawingCache();
            return bitmap;
        }
    
        /**
         * 通过系统录屏截图
         */
        public static void getScreenProjection(FragmentActivity activity, Callback<Bitmap> callback) {
            //调用系统服务，会弹出一个是否允许录屏的对话框
            MediaProjectionManager mediaProjectionManager = (MediaProjectionManager) activity.getSystemService(Context.MEDIA_PROJECTION_SERVICE);
            Intent intent = mediaProjectionManager.createScreenCaptureIntent();
            ActivityLauncher.init(activity).startActivityForResult(intent, (resultCode, data) -> {
                MediaProjection mediaProjection = mediaProjectionManager.getMediaProjection(resultCode, data);
                //返回null，说明用户拒绝
                if (mediaProjection == null) {
                    return;
                }
                Point screenSize = DisplayUtil.getResolution(activity);
                /*
                The producer output buffer format 0x1 doesn't match the ImageReader's configured buffer format 0x4.
                所以各式只能用8888，不能用565
                 */
                ImageReader imageReader = ImageReader.newInstance(screenSize.x, screenSize.y, PixelFormat.RGBA_8888, 1);
                int densityDpi = DisplayUtil.getDensityDpi(activity);
                VirtualDisplay virtualDisplay = mediaProjection.createVirtualDisplay("screen-mirror",
                        screenSize.x,
                        screenSize.y,
                        densityDpi,
                        DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,
                        imageReader.getSurface(),
                        null,
                        //传null表示在回调在主线程中执行
                        null);
                //在获取Image的时候，得先暂停1秒左右，不然就会获取失败(原因未知)
                SystemClock.sleep(1000);
                Image image = imageReader.acquireLatestImage();
                Bitmap bitmap = BitmapUtil.fromImage(image);
                image.close();
                callback.invoke(bitmap);
                virtualDisplay.release();
            });
        }
    
        /*
         Android 在5.0 之后支持了实时录屏的功能。
         通过实时录屏我们可以拿到截屏的图像。
         同时可以通过在Service中处理实现后台的录屏。
         */
        @RequiresApi(Build.VERSION_CODES.O)
        public static void getViewBySystem(Activity activity, View view, Callback<Bitmap> callback) {
            int width = view.getWidth();
            int height = view.getHeight();
            //这里只能用8888，不能用其它的，否则一片黑取不到图像
            Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888, true);
            Window window = activity.getWindow();
            final int[] location = new int[2];
            view.getLocationInWindow(location);
            Rect rect = new Rect(location[0], location[1], location[0] + view.getWidth(), location[1] + view.getHeight());
            final Handler handler = new Handler(Looper.getMainLooper());
            PixelCopy.request(window, rect, bitmap, copyResult -> {
                callback.invoke(copyResult == PixelCopy.SUCCESS ? bitmap : null);
            }, handler);
        }
    
        /**
         * 截取视图
         */
        public static Bitmap getView(View view) {
            view.setDrawingCacheEnabled(true);
            view.buildDrawingCache();
            Bitmap cache = view.getDrawingCache();
            Bitmap bitmap = BitmapUtil.clone(cache);
            view.setDrawingCacheEnabled(false);
            view.destroyDrawingCache();
            return bitmap;
        }
    
        /**
         * 截取 ScrollView 视图
         */
        public static Bitmap getRecyclerView(RecyclerView recyclerView, int maxSize) {
            RecyclerView.Adapter adapter = recyclerView.getAdapter();
            int height = 0;
            //取列表项和缓存项中的最小值
            int size = Math.min(maxSize, adapter.getItemCount());
            //把每个item的绘图缓存存储在LruCache中
            LruCache<Integer, Bitmap> bitmapCache = new LruCache<>(maxSize);
            for (int i = 0; i < size; i++) {
                //手动调用创建和绑定ViewHolder方法，
                RecyclerView.ViewHolder holder = adapter.createViewHolder(recyclerView, adapter.getItemViewType(i));
                adapter.onBindViewHolder(holder, i);
                /*
                测量
                MeasureSpec.EXACTLY - 视图应该是这么多像素，无论它实际上有多大。
                MeasureSpec.AT_MOST - 如果视图的尺寸较小，则视图可以是此尺寸或更小。
                MeasureSpec.UNSPECIFIED - 视图可以是它需要的任何大小，以显示它需要显示的内容。
                 */
                holder.itemView.measure(
                        View.MeasureSpec.makeMeasureSpec(recyclerView.getWidth(), View.MeasureSpec.EXACTLY),
                        View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
                //布局
                holder.itemView.layout(0, 0,
                        holder.itemView.getMeasuredWidth(),
                        holder.itemView.getMeasuredHeight());
                //开启视图绘制缓存
                holder.itemView.setDrawingCacheEnabled(true);
                holder.itemView.buildDrawingCache();
                Bitmap drawingCache = holder.itemView.getDrawingCache();
                Bitmap cacheClone = BitmapUtil.clone(drawingCache);
                if (cacheClone != null) {
                    bitmapCache.put(i, cacheClone);
                }
                //禁用视图绘制缓存
                holder.itemView.setDrawingCacheEnabled(false);
                //销毁视图绘制缓存
                holder.itemView.destroyDrawingCache();
                //获取itemView的实际高度并累加
    //            height += holder.itemView.getMeasuredHeight();
                height += cacheClone.getHeight();
            }
            //这里只能用8888，不能用其它的，否则一片黑取不到图像
            Bitmap dstBitmap = Bitmap.createBitmap(recyclerView.getWidth(), height, Bitmap.Config.ARGB_8888);
            Canvas canvas = new Canvas(dstBitmap);
            Paint paint = new Paint();
            for (int i = 0, top = 0; i < size; i++) {
                Bitmap bitmap = bitmapCache.get(i);
                canvas.drawBitmap(bitmap, 0, top, paint);
                top += bitmap.getHeight();
            }
            return dstBitmap;
        }
    
        /**
         * 截取 ScrollView 视图
         */
        public static Bitmap getScrollView(ScrollView scrollView) {
            int height = 0;
            //ScrollView理论上只有一个子View
            for (int i = 0; i < scrollView.getChildCount(); i++) {
                height += scrollView.getChildAt(i).getHeight();
            }
            //这里只能用8888，不能用其它的，否则一片黑取不到图像
            Bitmap bitmap = Bitmap.createBitmap(scrollView.getWidth(), height, Bitmap.Config.ARGB_8888);
            Canvas canvas = new Canvas(bitmap);
            scrollView.draw(canvas);
            return bitmap;
        }
    }

public interface Callback<T> {
        void invoke() {}
    }