裁剪方形图像到圆圈 - 以编程方式

Question

我正在寻找过去的一天,但我没有成功.

我从API获取图像,然后使用以下代码将其下载到位图文件.

private Bitmap DownloadImage(String URL) 
    {
        Bitmap bitmap = null;
        InputStream in = null;
        try 
        {
            in = OpenHttpConnection(URL);
            bitmap = BitmapFactory.decodeStream(in);
            in.close();
        }
        catch (IOException e1) 
        {
            e1.printStackTrace();
        }
        return bitmap;
    }

    private InputStream OpenHttpConnection(String urlString) throws IOException 
    {
        InputStream in = null;
        int response = -1;

        URL url = new URL(urlString);
        URLConnection conn = url.openConnection();

        if (!(conn instanceof HttpURLConnection))
            throw new IOException("Not an HTTP connection");

        try 
        {
            HttpURLConnection httpConn = (HttpURLConnection) conn;
            httpConn.setAllowUserInteraction(false);
            httpConn.setInstanceFollowRedirects(true);
            httpConn.setRequestMethod("GET");
            httpConn.connect();

            response = httpConn.getResponseCode();
            if (response == HttpURLConnection.HTTP_OK) 
            {
                in = httpConn.getInputStream();
            }
        }
        catch (Exception ex) 
        {
            throw new IOException("Error connecting");
        }
        return in;
    }

我将图像作为正方形,我想裁剪四个角并使其成为圆形图像.有没有可能实现的方法？

欢迎任何相关的答案.提前致谢 .

Answer 1

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        DrawingView dv = new DrawingView(this);
        setContentView(dv);
    }

    class DrawingView extends View {
        Bitmap bitmap;

        public DrawingView(Context context) {
            super(context);
            bitmap = BitmapFactory.decodeResource(context.getResources(),
                    R.drawable.glossy_overlay);

        }

        @Override
        public void onDraw(Canvas canvas) {
            Paint paint = new Paint();
            // paint.setColor(Color.CYAN);
            canvas.drawBitmap(getclip(), 30, 20, paint);
        }

        public Bitmap getclip() {
            Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
                    bitmap.getHeight(), Config.ARGB_8888);
            Canvas canvas = new Canvas(output);
            final int color = 0xff424242;
            final Paint paint = new Paint();
            final Rect rect = new Rect(0, 0, bitmap.getWidth(),
                    bitmap.getHeight());

            paint.setAntiAlias(true);
            canvas.drawARGB(0, 0, 0, 0);
            // paint.setColor(color);
            canvas.drawCircle(bitmap.getWidth() / 2,
                    bitmap.getHeight() / 2, bitmap.getWidth() / 2, paint);
            paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
            canvas.drawBitmap(bitmap, rect, rect, paint);
            return output;
        }
    }
}

Answer 2

一旦检索到的位图RoundedBitmapDrawableFactory可以被用来生成一个RoundedBitmapDrawable从V4支持库.这Drawable然后可以被施加到一个ImageView或直接吸引到一个Canvas.

// Create the RoundedBitmapDrawable.
RoundedBitmapDrawable roundDrawable = RoundedBitmapDrawableFactory.create(getResources(), bitmap);
roundDrawable.setCircular(true);

// Apply it to an ImageView.
ImageView imageView = (ImageView)findViewById(R.id.imageView);
imageView.setImageDrawable(roundDrawable);

// Alternatively, draw it to an canvas (e.g. in onDraw where a Canvas is available).
// setBounds since there's no View handling size and positioning.
roundDrawable.setBounds(left, top, right, bottom);
roundDrawable.draw(canvas);

Answer 3

使用函数blow在位图上绘制圆,然后将带圆圈的位图设置为imageview

public static Bitmap getclip(Bitmap bitmap) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
            bitmap.getHeight(), Config.ARGB_8888);
    Canvas canvas = new Canvas(output);

    final Paint paint = new Paint();
    final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    canvas.drawCircle(bitmap.getWidth() / 2, bitmap.getHeight() / 2,
            bitmap.getWidth() / 2, paint);
    paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
    canvas.drawBitmap(bitmap, rect, rect, paint);
    return output;
}