android - 在来自服务器的图像上动态添加文本

Question

我正在通过网络服务在运行时从服务器下载一些图像，我如何将文本放在它上面。

我已经使用了这段代码，但这给出了异常。

网址 = 新网址（imgUrl）；

            HttpURLConnection urlConnection = (HttpURLConnection) url
                    .openConnection();
            urlConnection.connect();

            iStream = urlConnection.getInputStream();

            File cacheDirectory = getBaseContext().getCacheDir();

            // Temporary file to store the downloaded image
            File tmpFile = new File(cacheDirectory.getPath() + "/wpta_"
                    + position + ".png");

            // The FileOutputStream to the temporary file
            FileOutputStream fOutStream = new FileOutputStream(tmpFile);

            // Creating a bitmap from the downloaded inputstream
            Bitmap b = BitmapFactory.decodeStream(iStream);

            // Writing the bitmap to the temporary file as png file
            b.compress(Bitmap.CompressFormat.PNG, 50, fOutStream);

            Canvas g = new Canvas(b);
            Paint p = new Paint();
            p.setColor(Color.BLACK);
            p.setAntiAlias(true);
            g.drawText("Text", 10, 10, p);

            // Flush the FileOutputStream
            fOutStream.flush();

            // Close the FileOutputStream
            fOutStream.close();

            // Create a hashmap object to store image path and its position
            // in the listview
            HashMap<String, Object> hmBitmap = new HashMap<String, Object>();

            // Storing the path to the temporary image file
            hmBitmap.put("flag", tmpFile.getPath());

            // Storing the position of the image in the listview
            hmBitmap.put("position", position);

Answer 1

首先想到的是在对象 中使用draw(Canvas)方法。TextView

Canvas object您可以使用以下方法创建一个bitmap：

new Canvas(bitmap)

然后将 a 绘制TextView到同一个 Canvas 中。