长截图分享，NestedScrollView、RecyclerView、ListView、WebView等实现长截图，RecyclerView、ListView的Item数据可异步加载
public static Bitmap shotNestedScrollView(NestedScrollView nestedScrollView) {
if (nestedScrollView == null) {
return null;
}
try {
int h = 0;
// 获取ScrollView实际高度
for (int i = 0; i < nestedScrollView.getChildCount(); i++) {
h += nestedScrollView.getChildAt(i).getHeight();
}
// 创建对应大小的bitmap
Bitmap bitmap = Bitmap.createBitmap(nestedScrollView.getWidth(), h, Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(bitmap);
nestedScrollView.draw(canvas);
// 保存图片
savePicture(nestedScrollView.getContext(), bitmap);
return bitmap;
} catch (OutOfMemoryError oom) {
return null;
}
}
public static Bitmap shotListView(ListView listView) {
if (listView == null) {
return null;
}
try {
ListViewAdapter adapter = (ListViewAdapter) listView.getAdapter();
Bitmap bigBitmap = null;
if (adapter != null) {
int size = adapter.getCount();
int height = 0;
Paint paint = new Paint();
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> bitmapCache = new LruCache<>(cacheSize);
SparseIntArray bitmapTop = new SparseIntArray(size);
for (int i = 0; i < size; i++) {
View childView = adapter.getConvertView(i, null, listView);
adapter.onBindViewSync(i, childView, listView);
childView.measure(
View.MeasureSpec.makeMeasureSpec(listView.getWidth(), View.MeasureSpec.EXACTLY),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED)
);
childView.layout(
0,
0,
childView.getMeasuredWidth(),
childView.getMeasuredHeight()
);
childView.setDrawingCacheEnabled(true);
childView.buildDrawingCache();
Bitmap drawingCache = childView.getDrawingCache();
if (drawingCache != null) {
bitmapCache.put(String.valueOf(i), drawingCache);
}
bitmapTop.put(i, height);
height += childView.getMeasuredHeight();
}
bigBitmap = Bitmap.createBitmap(listView.getMeasuredWidth(), height, Bitmap.Config.ARGB_8888);
Canvas bigCanvas = new Canvas(bigBitmap);
Drawable lBackground = listView.getBackground();
if (lBackground instanceof ColorDrawable) {
ColorDrawable lColorDrawable = (ColorDrawable) lBackground;
int lColor = lColorDrawable.getColor();
bigCanvas.drawColor(lColor);
}
for (int i = 0; i < size; i++) {
Bitmap bitmap = bitmapCache.get(String.valueOf(i));
bigCanvas.drawBitmap(bitmap, 0, bitmapTop.get(i), paint);
bitmap.recycle();
}
}
return bigBitmap;
} catch (OutOfMemoryError oom) {
return null;
}
}
public static Bitmap shotRecyclerView(RecyclerView recyclerView) {
if (recyclerView == null) {
return null;
}
try {
RecyclerViewAdapter adapter = (RecyclerViewAdapter) recyclerView.getAdapter();
Bitmap bigBitmap = null;
if (adapter != null) {
int size = adapter.getItemCount();
int height = 0;
Paint paint = new Paint();
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> bitmapCache = new LruCache<>(cacheSize);
SparseIntArray bitmapLeft = new SparseIntArray(size);
SparseIntArray bitmapTop = new SparseIntArray(size);
for (int i = 0; i < size; i++) {
RecyclerView.ViewHolder holder = adapter.createViewHolder(recyclerView, adapter.getItemViewType(i));
adapter.onBindViewSync(holder, i);
RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) holder.itemView.getLayoutParams();
holder.itemView.measure(
View.MeasureSpec.makeMeasureSpec(recyclerView.getWidth() - layoutParams.leftMargin - layoutParams.rightMargin, View.MeasureSpec.EXACTLY),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED)
);
holder.itemView.layout(
layoutParams.leftMargin,
layoutParams.topMargin,
holder.itemView.getMeasuredWidth() + layoutParams.leftMargin,
holder.itemView.getMeasuredHeight() + layoutParams.topMargin
);
holder.itemView.setDrawingCacheEnabled(true);
holder.itemView.buildDrawingCache();
Bitmap drawingCache = holder.itemView.getDrawingCache();
if (drawingCache != null) {
bitmapCache.put(String.valueOf(i), drawingCache);
}
height += layoutParams.topMargin;
bitmapLeft.put(i, layoutParams.leftMargin);
bitmapTop.put(i, height);
height += holder.itemView.getMeasuredHeight() + layoutParams.bottomMargin;
}
bigBitmap = Bitmap.createBitmap(recyclerView.getMeasuredWidth(), height, Bitmap.Config.ARGB_8888);
Canvas bigCanvas = new Canvas(bigBitmap);
Drawable lBackground = recyclerView.getBackground();
if (lBackground instanceof ColorDrawable) {
ColorDrawable lColorDrawable = (ColorDrawable) lBackground;
int lColor = lColorDrawable.getColor();
bigCanvas.drawColor(lColor);
}
for (int i = 0; i < size; i++) {
Bitmap bitmap = bitmapCache.get(String.valueOf(i));
bigCanvas.drawBitmap(bitmap, bitmapLeft.get(i), bitmapTop.get(i), paint);
bitmap.recycle();
}
}
return bigBitmap;
} catch (OutOfMemoryError oom) {
return null;
}
}
public static Bitmap shotWebView(WebView webView) {
try {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
// Android5.0以上
float scale = webView.getScale();
int width = webView.getWidth();
int height = (int) (webView.getContentHeight() * scale + 0.5);
Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
webView.draw(canvas);
// 保存图片
savePicture(webView.getContext(), bitmap);
return bitmap;
} else {
// Android5.0以下
Picture picture = webView.capturePicture();
int width = picture.getWidth();
int height = picture.getHeight();
if (width > 0 && height > 0) {
Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
picture.draw(canvas);
// 保存图片
savePicture(webView.getContext(), bitmap);
return bitmap;
}
return null;
}
} catch (OutOfMemoryError oom) {
return null;
}
}
5. 异步加载数据截图实现（以ListView为例）
public void onBindViewSync(final int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.list_item_list, parent, false);
holder = new ViewHolder(convertView);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
// List中的Item的LayoutParam是直接继承自ViewGroup中的LayoutParam。 不包含有margin信息。
// 所以在ListView中父节点设置的值会失效。
if (position == 0) {
// 设置margin
ViewUtils.setViewMargin(holder.mRlGameInfo, true, 25, 100, 25, 0);
} else if (position == getCount() - 1) {
// 设置margin
ViewUtils.setViewMargin(holder.mRlGameInfo, true, 25, 15, 25, 150);
} else {
// 设置margin
ViewUtils.setViewMargin(holder.mRlGameInfo, true, 25, 15, 25, 0);
}
try {
File gameImageFile = Glide.with(mContext)
.load(mDatas.get(position))
.downloadOnly(0, 0)
.get();
Bitmap gameImageBitmap = BitmapFactory.decodeFile(gameImageFile.getAbsolutePath());
File gameIconFile = Glide.with(mContext)
.load(mDatas.get(position))
.downloadOnly(0, 0)
.get();
Bitmap gameIconBitmap = BitmapFactory.decodeFile(gameIconFile.getAbsolutePath());
holder.mIvGameImage.setImageBitmap(gameImageBitmap);
holder.mIvGameIcon.setImageBitmap(gameIconBitmap);
holder.mTvGameName.setText(String.format(Locale.getDefault(), "《将进酒》李白%d", position));
} catch (ExecutionException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}public View getConvertView(final int position, View convertView, final ViewGroup parent) {
final ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.list_item_list, parent, false);
holder = new ViewHolder(convertView);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
return convertView;
}Observable.defer(
new Callable<ObservableSource<Bitmap>>() {
@Override
public ObservableSource<Bitmap> call() throws Exception {
return new ObservableSource<Bitmap>() {
@Override
public void subscribe(Observer<? super Bitmap> observer) {
// 开始截图
observer.onNext(ScreenShotUtils.shotListView(mLvList));
}
};
}
})
.subscribeOn(Schedulers.computation())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Consumer<Bitmap>() {
@Override
public void accept(Bitmap bitmap) throws Exception {
// 保存图片
File file = ScreenShotUtils.savePicture(mContext, bitmap);
Toast.makeText(mContext, "图片已保存至 " + file.getAbsolutePath(), Toast.LENGTH_SHORT).show();
}
});
