Question

我想实现“扩展”按钮以使图像适合选定的边界。

public void extendS(View v){
        ImageView iv = current;
        double width = gallery.getWidth();
        double hight= gallery.getHeight();

        double aspect = (width+0)/(hight+0);
        Log.d("aspect", "w: "+width+" h: "+hight+" a: "+aspect);
        if (aspect>1){
            hight/=aspect;
        }else{
            width*=aspect;
        }
        Bitmap b = ((BitmapDrawable) iv.getDrawable()).getBitmap();
//      Matrix matrix = new Matrix();
        Log.d("aspect", "w: "+width+" h: "+hight+" a: "+aspect);
         Bitmap scale = Bitmap.createBitmap(b, 0, 0, (int)width, (int)hight);
         iv.setImageBitmap(scale);

我收到的错误：07-16 12：26：36.855：E / AndroidRuntime（12647）：引起：java.lang.IllegalArgumentException：y + height必须是＆lt; = bitmap.height（）从我的观点来看，这个错误似乎有点奇怪

Answer 1

public static Bitmap resizeBitmap(Bitmap photo, float x, float y) {

    try {
        // get current bitmap width and height
        int width = photo.getWidth();
        int height = photo.getHeight();

        // determine how much to scale
        float scaleWidth = x / width;
        float scaleHeight = y / height;

        // create the matrix for the manipulation
        Matrix matrix = new Matrix();
        // resize the bitmap
        matrix.postScale(scaleWidth, scaleHeight);

        // recreate the new bitmap
        Bitmap resizebitmap = Bitmap.createBitmap(photo, 0, 0, width,
                height, matrix, false);
        return resizebitmap;

    } catch (NullPointerException e) {
        e.printStackTrace();
    } catch (OutOfMemoryError e) {
        e.printStackTrace();
        System.gc();
    }
    return null;
}

Answer 2

您收到此错误是因为您尝试访问原始位图区域之外的数据。你实际上非常接近，你只是使用了错误的Bitmap.createBitmap（）函数。尝试使用不同大小的原始源创建位图：

Bitmap.createScaledBitmap(b, (int)width, (int)hight, true);

另外，你的宽高比是错误的。提示：您无需担心此代码的宽高比。

无法重新缩放位图

2 个答案: