Question

我正在尝试从res / drawable文件夹中加载图片。我使用了Android开发者Link中的指南。由于某种原因它不工作。我得到的唯一错误是“SPAN_EXCLUSIVE_EXCLUSIVE跨度不能有一个零长度”，我研究过。显然它与自定义键盘有关，但我根本不使用文本输入。应用程序本身不是崩溃。我希望你们能帮助我:) 布局文件只包含一个带有ImageView的RelativeLayout。

public class PixelActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_pixel);
    String uri = "@drawable-hdpi/testbild.png";
    final int imageResource = getResources().getIdentifier(uri, null, getPackageName());


    final ImageView iv = (ImageView) findViewById(R.id.imageview1);

    //int imageHeight = options.outHeight;
    //int imageWidth = options.outWidth;
    //String imageType = options.outMimeType;
    new Thread(new Runnable()
    {

        public void run()
        {
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeResource(getResources(), imageResource, options);


            iv.post(new Runnable()
            {

                public void run()
                {
                    iv.setImageBitmap(decodeSampledBitmapFromResources(getResources(),imageResource,iv.getWidth(),iv.getHeight()));
                    //iv.setImageResource(R.drawable.testbild);
                }
            });
        }
    });






}

public static int calculateInSampleSize(BitmapFactory.Options options,int reqWidth, int reqHeight)
{
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;

    if(height > reqHeight || width > reqWidth)
    {
        final int heightRatio = Math.round((float)height/(float)reqHeight);
        final int widthRatio = Math.round((float)width/(float)reqWidth);

        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }

    return inSampleSize;
}

public static Bitmap decodeSampledBitmapFromResources(Resources res, int resId, int reqWidth, int reqHeight)
{
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(res, resId, options);

    options.inSampleSize = calculateInSampleSize(options,reqWidth,reqHeight);
    options.inJustDecodeBounds = false;

    return BitmapFactory.decodeResource(res, resId, options);
}

}

Answer 1

String uri = "@drawable-hdpi/testbild.png";

这是无效的。删除-hdpi部分和.png部分，然后重试。或者，切换到向getIdentifier()提供所有三个参数：

final int imageResource = getResources().getIdentifier("testbild", "drawable", getPackageName());

ImageView无法加载图片（jpg，png，...）

1 个答案: