问题描述

camera activity报错空指针异常

camera intent：

fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);

这部分报空指针异常的错误，谁能解释一下为什么，还有需要改什么地方？

button_1.setOnClickListener(new View.OnClickListener() {

    public void onClick(View v) {
        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");

        fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE); // 创建一个文件来保存图像
        intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); //设置图像的文件名 

        startActivityForResult(intent, TAKE_PICTURE);
    }
});

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_CODE) {
        if (resultCode == RESULT_OK) {
            //  获取图像，保存在 Intent中fileUri里
            Toast.makeText(this, "Image saved to:n" +
                     data.getData(), Toast.LENGTH_LONG).show();
        } else if (resultCode == RESULT_CANCELED) {
            // 用户取消图像获取
        } else {
            // 图像获取失败
        }
    }
}

解决方案

//创建拍照 Intent并将控制权返回给调用的程序
  Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
  fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
  //创建保存图片的文件
  intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);

你把Intent这样初始化一下看看

解决方案二：

应该是fileUri的问题
你试着这样改下

fileUri=Uri.fromFile(new File(Environment .getExternalStorageDirectory(), "temp.jpg"))

解决方案三：

试一下这个方法：

public class Camera extends Activity
      {
     private static final int CAMERA_REQUEST = 1888;
     private String selectedImagePath;
     WebView webview;
     String fileName = "capturedImage.jpg";
     private static Uri mCapturedImageURI; 

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        Intent cameraIntent = new Intent(ACTION_IMAGE_CAPTURE);
        startActivityForResult(cameraIntent, CAMERA_REQUEST);
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data)
    {
        if (resultCode == RESULT_OK) {
            if (requestCode == CAMERA_REQUEST)
            {
                Bitmap photo = (Bitmap) data.getExtras().get("data");
                ByteArrayOutputStream bytes = new ByteArrayOutputStream();
                photo.compress(Bitmap.CompressFormat.JPEG, 40, bytes);
                Random randomGenerator = new Random();randomGenerator.nextInt();
                String newimagename=randomGenerator.toString()+".jpg";
                File f = new File(Environment.getExternalStorageDirectory()
                                        + File.separator + newimagename);
                try {
                    f.createNewFile();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

                try {
                    fo = new FileOutputStream(f.getAbsoluteFile());
                } catch (FileNotFoundException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                try {
                    fo.write(bytes.toByteArray());
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                    uri=f.getAbsolutePath();
        //你保存图像的url
          }