Question

我目前正在将现有的iOS应用移植到Android上，并遇到了需要在布局中裁剪视图内容的障碍。

在iOS中，我只是访问视图层，然后相应地设置layer.contentsRect。

在Android中，我认为我找到了GLSurfaceView类的等效函数 - setClipBounds，但这仅适用于支持API级别18的设备，并在我的Galaxy S上引发NoSuchMethodError异常3。

是否有人有替代解决方案（或支持库）来剪裁或裁剪API级别9（2.3）的视图内容？感谢。

Answer 1

这里是我在xamarin（c＃）中编写的一些裁剪代码，它是从Java移植的，你需要自己进行转换，类名大致相同，方法和属性公开为get / set在Java。

代码将位图裁剪为圆形，类似于facebook浮动面：）

    public static class BitmapHelpers
{
    public static Bitmap LoadAndResizeBitmap (this string fileName, int width, int height)
    {
        // First we get the the dimensions of the file on disk
        BitmapFactory.Options options = new BitmapFactory.Options { InJustDecodeBounds = true };
        BitmapFactory.DecodeFile (fileName, options);

        // Next we calculate the ratio that we need to resize the image by
        // in order to fit the requested dimensions.
        int outHeight = options.OutHeight;
        int outWidth = options.OutWidth;
        int inSampleSize = 1;

        if (outHeight > height || outWidth > width) {
            inSampleSize = outWidth > outHeight
                               ? outHeight / height
                               : outWidth / width;
        }

        // Now we will load the image and have BitmapFactory resize it for us.
        options.InSampleSize = inSampleSize;
        options.InJustDecodeBounds = false;
        Bitmap resizedBitmap = BitmapFactory.DecodeFile (fileName, options);

        return resizedBitmap;
    }

    public static Bitmap GetCroppedBitmap (Bitmap bitmap)
    {
        Bitmap output = Bitmap.CreateBitmap (bitmap.Width,
                                     bitmap.Height, global::Android.Graphics.Bitmap.Config.Argb8888);
        Canvas canvas = new Canvas (output);

        int color = -1;
        Paint paint = new Paint ();
        Rect rect = new Rect (0, 0, bitmap.Width, bitmap.Height);

        paint.AntiAlias = true;
        canvas.DrawARGB (0, 0, 0, 0);
        paint.Color = Color.White;

        canvas.DrawCircle (bitmap.Width / 2, bitmap.Height / 2,
            bitmap.Width / 2, paint);
        paint.SetXfermode (new PorterDuffXfermode (global::Android.Graphics.PorterDuff.Mode.SrcIn));
        canvas.DrawBitmap (bitmap, rect, rect, paint);

        return output;
    }
}

Android剪辑/裁剪视图内容

1 个答案: