来自官方网站:http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

ImageView image = (ImageView) findViewById(R.id.imagePreview);           
try {
    image.setImageBitmap(decodeSampledBitmap(picFilename));
} catch (Exception e) {
    e.printStackTrace();
}

方法如下:

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

        if (height > reqHeight || width > reqWidth) {

            final int halfHeight = height / 2;
            final int halfWidth = width / 2;

            // Calculate the largest inSampleSize value that is a power of 2 and keeps both
            // height and width larger than the requested height and width.
            while ((halfHeight / inSampleSize) > reqHeight
                    && (halfWidth / inSampleSize) > reqWidth) {
                inSampleSize *= 2;
            }
        }

        return inSampleSize;
    }

    private Bitmap decodeSampledBitmap(String pathName,
            int reqWidth, int reqHeight) {

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(pathName, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeFile(pathName, options);
    }

//I added this to have a good approximation of the screen size: 
    private Bitmap decodeSampledBitmap(String pathName) {
        Display display = getWindowManager().getDefaultDisplay();
        Point size = new Point();
        display.getSize(size);
        int width = size.x;
        int height = size.y;
        return decodeSampledBitmap(pathName, width, height);
    }   

mageView.setImageResource(R.id.img);

你还可以使用:

    File imgFile = new  File(“filepath”);
    if(imgFile.exists())
    {
        ImageView myImage = new ImageView(this);
        myImage.setImageURI(Uri.fromFile(imgFile));

    }

这为您隐式地完成位图解码。

Labeeb是对的，为什么你需要设置图像使用路径，如果你的资源已经放在资源文件夹，

只有当图像存储在SD-Card中时，才需要这种路径。

尝试下面的代码来设置存储在sd卡中的文件中的位图图像。

File imgFile = new  File("/sdcard/Images/test_image.jpg");

if(imgFile.exists()){

    Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());

    ImageView myImage = (ImageView) findViewById(R.id.imageviewTest);

    myImage.setImageBitmap(myBitmap);

}

并将此权限包含在manifest文件中:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

onLoadImage满载

private void onLoadImage(final String imagePath) {
    ImageSize targetSize = new ImageSize(imageView.getWidth(), imageView.getHeight()); // result Bitmap will be fit to this size

    //ImageLoader imageLoader = ImageLoader.getInstance(); // Get singleto
    com.nostra13.universalimageloader.core.ImageLoader imageLoader = com.nostra13.universalimageloader.core.ImageLoader.getInstance();
    imageLoader.init(ImageLoaderConfiguration.createDefault(getContext()));

    imageLoader.loadImage(imagePath, targetSize, new SimpleImageLoadingListener() {
        @Override
        public void onLoadingStarted(final String imageUri, View view) {
            super.onLoadingStarted(imageUri, view);

            progress2.setVisibility(View.VISIBLE);

            new Handler().post(new Runnable() {
                public void run() {
                    progress2.setColorSchemeResources(android.R.color.holo_green_light, android.R.color.holo_orange_light, android.R.color.holo_red_light);

                    // Picasso.with(getContext()).load(imagePath).into(imageView);
                    // Picasso.with(getContext()).load(imagePath) .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE).into(imageView);

                    Glide.with(getContext())
                            .load(imagePath)
                            .asBitmap()
                            .into(imageView);
                }
          });
        }

        @Override
        public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
            if (view == null) {
                progress2.setVisibility(View.INVISIBLE);
            }
            // else { 
              Log.e("onLoadImage", "onLoadingComplete");
            //   progress2.setVisibility(View.INVISIBLE);
            // }
            // setLoagingCompileImage();
        }

        @Override
        public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
            super.onLoadingFailed(imageUri, view, failReason);
            if (view == null) {
                progress2.setVisibility(View.INVISIBLE);
            }
            Log.e("onLoadingFailed", imageUri);
            Log.e("onLoadingFailed", failReason.toString());
        }

        @Override
        public void onLoadingCancelled(String imageUri, View view) {
            super.onLoadingCancelled(imageUri, view);
            if (view == null) {
                progress2.setVisibility(View.INVISIBLE);
            }
            Log.e("onLoadImage", "onLoadingCancelled");
        }
    });
}

大多数答案都是有效的，但没有人提到高分辨率的图像会降低应用程序的速度，在我的情况下，我使用了imagesrecyclerview，它在30张图像中占用了0.9 GB的设备内存。

我/编舞:跳过73帧!应用程序可能也在这样做 它的主线有很多工作要做。

解决方法很简单，你可以像这样降低质量:降低位图的分辨率

但我用简单的方式，Glide处理剩下的工作

fanContext?.let {
            Glide.with(it)
                .load(Uri.fromFile(File(item.filePath)))
                .into(viewHolder.imagePreview)
        }