Question

在设备中使用高分辨率图像时出现问题。

 imageview a;
InputStream ims = getAssets().open("sam.png");//sam.png=520*1400 device=320*480 or 480*800
Drawable d=Drawable.createFromStream(ims, null);
a.setLayoutParams(new        LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
a.setImageDrawable(d);

通过使用上面的代码图像在顶部和底部留下空间到下一个内容或者如果我通过给出固定的px缩小图像，它的尺寸得到模糊图像。无论如何要解决这个问题？

Answer 1

尝试创建Bitmap而不是Drawable：

Bitmap bmp = BitmapFactory.decodeStream(ims);
a.setImageBitmap(bmp);

看起来Android会根据屏幕密度对drawable进行一些技巧。

Answer 2

希望以下解决方案有所帮助。您可以使您的imageView具有固定大小，并将该imageView的宽度和高度传递给calculateInSampleSize方法。根据图像大小，它将决定是否对图像进行下采样。</ p>

public Bitmap getBitmap(Context context, final String imagePath)
{
    AssetManager assetManager = context.getAssets();
    InputStream inputStream = null;
    Bitmap bitmap = null;
    try
    {
        inputStream = assetManager.open(imagePath);         

        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inScaled = true;
        options.inJustDecodeBounds = true;

        // First decode with inJustDecodeBounds=true to check dimensions
        bitmap = BitmapFactory.decodeStream(inputStream);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, requiredWidth, requiredHeight);

        options.inJustDecodeBounds = false;

        bitmap = BitmapFactory.decodeStream(inputStream);
    }
    catch(Exception exception) 
    {
        exception.printStackTrace();
        bitmap = null;
    }

    return bitmap;
}


public int calculateInSampleSize(BitmapFactory.Options options, final int requiredWidth, final int requiredHeight) 
{
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if(height > requiredHeight || width > requiredWidth) 
    {
        if(width > height) 
        {
            inSampleSize = Math.round((float)height / (float)requiredHeight);
        } 
        else 
        {
            inSampleSize = Math.round((float)width / (float)requiredWidth);
        }
    }

    return inSampleSize;
}

Android：问题图像分辨率

2 个答案: