当我使用Intent.getExtras时遇到NullPointerException

Question

在方法performCrop（）中，代码如下：

public void performCrop() {
    try {
        Intent cropIntent = new Intent("com.android.camera.action.CROP");
        cropIntent.setDataAndType(picUri, "image/*");
        cropIntent.putExtra("crop", "true");
        ...
        startActivityForResult(cropIntent, PIC_CROP);
    } catch (ActivityNotFoundException anfe) {
        ...
    }

在方法onActivityResult中，代码：

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // TODO Auto-generated method stub
    ...
    Bundle extras = data.getExtras();//Here occurs the exception
    ...
    }
}