我有一个图像发送给我通过一个JSON字符串。我想这个字符串转换成图像在我的Andr​​oid应用程序，然后显示该图像。

I have an image being sent to me through a JSON string. I want to convert that string into an image in my android app and then display that image.

JSON字符串看起来是这样的：

The JSON string looks like this:

"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAVI..."

注：我截断字符串与...

Note: I truncated the string with a ...

我有一个函数，（我认为）的字符串转换成图像。我这样做对吗？

I've got a function that (I think) converts the string into an image. Am I doing this right?

public Bitmap ConvertToImage(String image){
    try{
        InputStream stream = new ByteArrayInputStream(image.getBytes());
        Bitmap bitmap = BitmapFactory.decodeStream(stream);
        Log.v("Ben", "Image Converted");                        
        return bitmap;  
    }
    catch (Exception e) {
        return null;            
    }
}

然后，我尝试在我的Andr​​oid活动像这样

Then I try to display it on my android activity like this

String image = jsonObject.getString("barcode_img");         
Bitmap myBitmap = this.ConvertToImage(image);
ImageView cimg = (ImageView)findViewById(R.id.imageView1);

//Just to test, I've used this static image here, and it works fine. I've now commented this out
//cimg.setImageResource(R.drawable.qrcode);

//Now trying setting dynamic image
cimg.setImageBitmap(myBitmap);

然而，当我这样做，什么也不显示。我不明白，在logcat中的任何错误。我究竟做错了什么？

However, when I do this, nothing shows up. I don't get any errors in the logcat. What am I doing wrong?

感谢

推荐答案

我很担心，你需要去code只有Base64的字符串作为获取图像的字节，所以在

I'm worried about that you need to decode only the base64 string to get the image bytes, so in your

"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAVI..."

字符串，必须数据后得到的数据：影像\ / PNG; BASE64，，所以你得到的只是图像的字节数和c他们然后去$ C $：

string, you must get the data after data:image\/png;base64,, so you get only the image bytes and then decode them:

String imageDataBytes = completeImageData.substring(completeImageData.indexOf(",")+1);

InputStream stream = new ByteArrayInputStream(Base64.decode(imageDataBytes.getBytes(), Base64.DEFAULT));

这是一个code让你了解它是如何工作的，但如果你收到一个JSON对象，它应该做的的正确的方式：

This is a code so you understand how it works, but if you receive a JSON object it should be done the correct way:

JS​​ON字符串转换为JSON对象。 下提取数据字符串键。 确保与图像/ PNG启动，所以你知道是一个PNG图像。 确保包含的base64 字符串，所以你知道，数据必须去codeD。 在德$ C C数据$后的base64 字符串来获取图像。 Converting the JSON string to a JSON object. Extract the String under data key. Make sure that starts with image/png so you know is a png image. Make sure that contains base64 string, so you know that data must be decoded. Decode the data after base64 string to get the image.