由setImageBitmap（）设置时，ImageView不会显示图像 [英] ImageView won't show image when set by setImageBitmap()

问题描述

我在显示sdcard上的现有图像时遇到问题。

I am having problems getting an existing image on the sdcard to display.

ImageView _photoView = (ImageView)findViewById(R.id.img_photo);

File photoFile = new File(Environment.getExternalStorageDirectory(), Session.PHOTO_FILE_NAME);
rawFileInputStream = new FileInputStream(photoFile);
Bitmap origPhoto = BitmapFactory.decodeStream(rawFileInputStream, null, new BitmapFactory.Options());

_photoView.setImageBitmap(origPhoto);
Log.d(TAG, origPhoto.getWidth() + " - " + origPhoto.getHeight());

照片确实存在且尺寸显示为显示，但ImageView标签内没有任何内容

The photo does exist and the dimensions show up as displayed, but nothing appears within the ImageView tag

<ImageView 
    android:id="@+id/img_photo"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" />

我试图将高度设置为固定大小，但我仍然看不到照片。

I tried to set the height to a fixed size, but I still can't see the photo.

我在SO上发现了一些关于这个问题的帖子，但都没有回答过。

I've seen a few posts on SO regarding this issue, but none of them have yet been answered.

任何想法？

**更新
如果我直接加载文件，而不是通过文件流工作

** Update If I load the file directly, instead of through a filestream it works

Bitmap origPhoto = BitmapFactory.decodeFile("/mnt/sdcard/" + Session.PHOTO_FILE_NAME);
double scale = MAX_WIDTH * 1.0 / origPhoto.getWidth();
int height = (int)(origPhoto.getHeight() * scale);
Bitmap scaledPhoto = Bitmap.createScaledBitmap(origPhoto, MAX_WIDTH, height, true);
_photoView.setImageBitmap(origPhoto);

但是如果我然后添加 Bitmap.createScaledBitmap（）方法调用它不再有效，图像不会显示。

but if I then add the Bitmap.createScaledBitmap() method call it no longer works and the image is not displayed.

推荐答案

我用Bitmap替换了文件流scaledPhoto = BitmapFactory.decodeFile（/ mnt / sdcard /+ Session.PHOTO_FILE_NAME）;它现在有效（更新中提到的内容）

I replaced the file streaming with Bitmap scaledPhoto = BitmapFactory.decodeFile("/mnt/sdcard/" + Session.PHOTO_FILE_NAME); and it now works (what was mentioned in the Update)

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