将mapView保存为图像而不在屏幕上呈现

Question

我正在创建类似于Strava的免费活动监控应用程序。使用vtm-android作为地图库。

我想将org.oscim.android.MapView保存为图像，而不将其渲染到屏幕上。

我找到了几个解决方案，如何将视图保存为图像，但遗憾的是，当视图未“附加”到现有组件树时，它们都不起作用。

我的期望是像这样初始化MapView：

final String MAP_FILE = "somemap.map";
MapView mapView = new MapView(mContext);

final org.oscim.map.Map map = mapView.map();
MapFileTileSource tileSource = new MapFileTileSource();

String mapPath = new File(Environment.getExternalStorageDirectory(), MAP_FILE).getAbsolutePath();
if (tileSource.setMapFile(mapPath)) {
    // Vector layer
    VectorTileLayer tileLayer = map.setBaseMap(tileSource);

    // Render theme
    map.setTheme(VtmThemes.DEFAULT);

    double latitude = 49.1625214;
    double longitude = 20.2644075;

    // Note: this map position is specific to Berlin area
    map.setMapPosition(latitude, longitude, 1 << 12);
}

mapView.layout(0, 0, 200, 200);

//Get the dimensions of the view so we can re-layout the view at its current size
//and create a bitmap of the same size
int width = view.getWidth();
int height = view.getHeight();

int measuredWidth = View.MeasureSpec.makeMeasureSpec(width, View.MeasureSpec.EXACTLY);
int measuredHeight = View.MeasureSpec.makeMeasureSpec(height, View.MeasureSpec.EXACTLY);

//Cause the view to re-layout
view.measure(measuredWidth, measuredHeight);
view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());

//Create a bitmap backed Canvas to draw the view into
Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);

//Now that the view is laid out and we have a canvas, ask the view to draw itself into the canvas
view.draw(canvas);

ByteBuffer byteBuffer = ByteBuffer.allocate(bitmap.getByteCount());
bitmap.copyPixelsToBuffer(byteBuffer);

//save bytes from bytebuffer to file or db

但是，不是地图图像，我得到完整的透明图像。

Answer 1

要拍摄屏幕截图，您需要在屏幕上进行渲染。没有渲染截图是不可能的

Answer 2

mapView.getDrawingCache（）

它将返回当前显示的位图。

Bitmap capturedScreen = Bitmap.createBitmap（mapView.getDrawingCache（））; imageView.setImageBitmap（capturedScreen）;

这里'capturedScreen'会给你mapview的图像。