我有以下代码，用于抓取图像（来自相机或图库），然后将其显示在ImageView上：
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
if(resultCode == RESULT_OK)
{
if(requestCode == 1888)
{
final boolean isCamera;
if(data == null)
{
isCamera = true;
}
else
{
final String action = data.getAction();
if(action == null)
{
isCamera = false;
}
else
{
isCamera = action.equals(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
}
}
Uri selectedImageUriTemp;
Uri selectedImageUri;
if(isCamera)
{
selectedImageUriTemp = outputFileUri;
Bitmap image = decodeFile(new File(selectedImageUriTemp.getPath()));
selectedImageUri = getImageUri(image);
}
else
{
selectedImageUriTemp = data == null ? null : data.getData();
Bitmap image = decodeFile(new File(selectedImageUriTemp.getPath()));
selectedImageUri = getImageUri(image);
}
Log.i("TAG", "IMAGEURI: " + selectedImageUri);
pictureThumb.setImageURI(selectedImageUri);
setRealPath(selectedImageUri);
}
}
}
private Uri getImageUri(Bitmap image){
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
image.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
String path = Images.Media.insertImage(getApplicationContext().getContentResolver(), image, "Title", null);
return Uri.parse(path);
}
如果我尝试使用Camera抓取图像，代码可以正常工作，但是当我尝试从Gallery中抓取图像时，它会返回NULL指针异常。
有人能建议我走向正确的方向吗？感谢
这是完整的日志：
02-12 10:34:56.249: E/AndroidRuntime(14607): FATAL EXCEPTION: main
02-12 10:34:56.249: E/AndroidRuntime(14607): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1888, result=-1, data=Intent { dat=content://media/external/images/media/29 }} to activity {com.gelliesmedia.thumbqoo/com.gelliesmedia.thumbqoo.PictureBooth}: java.lang.NullPointerException: uriString
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.app.ActivityThread.deliverResults(ActivityThread.java:3216)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.app.ActivityThread.handleSendResult(ActivityThread.java:3259)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.app.ActivityThread.access$1100(ActivityThread.java:138)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1253)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.os.Handler.dispatchMessage(Handler.java:99)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.os.Looper.loop(Looper.java:137)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.app.ActivityThread.main(ActivityThread.java:4954)
02-12 10:34:56.249: E/AndroidRuntime(14607): at java.lang.reflect.Method.invokeNative(Native Method)
02-12 10:34:56.249: E/AndroidRuntime(14607): at java.lang.reflect.Method.invoke(Method.java:511)
02-12 10:34:56.249: E/AndroidRuntime(14607): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:798)
02-12 10:34:56.249: E/AndroidRuntime(14607): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:565)
02-12 10:34:56.249: E/AndroidRuntime(14607): at dalvik.system.NativeStart.main(Native Method)
02-12 10:34:56.249: E/AndroidRuntime(14607): Caused by: java.lang.NullPointerException: uriString
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.net.Uri$StringUri.<init>(Uri.java:464)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.net.Uri$StringUri.<init>(Uri.java:454)
02-12 10:34:56.249: E/AndroidRuntime(14607): at android.net.Uri.parse(Uri.java:426)
02-12 10:34:56.249: E/AndroidRuntime(14607): at com.gelliesmedia.thumbqoo.PictureBooth.getImageUri(PictureBooth.java:224)
02-12 10:34:56.249: E/AndroidRuntime(14607): at com.gelliesmedia.thumbqoo.PictureBooth.onActivityResult(PictureBooth.java:206)
答案 0 :(得分：1)
你onActivityResult非常混乱。
尝试以这种方式编写代码.. 下面的方法是定义从相机捕获图像和分别从图库中拍摄图像。
protected void captureFromCamera() {
// TODO Auto-generated method stub
Intent cameraIntent = new Intent(
android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent,
UploadProfilePicActivity.REQ_CAMERA);
}
private void selectImageFromGallery() {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent,
getString(R.string.upload_profile_photo)),
UploadProfilePicActivity.REQ_GALLERY);
}
现在onActivityResult你的代码可能是这样的......
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == UploadProfilePicActivity.REQ_GALLERY && data != null
&& data.getData() != null) {
Uri _uri = data.getData();
try {
Bitmap profileBmp = Media.getBitmap(getContentResolver(), _uri);
if (profileBmp != null) {
image.setImageBitmap(profileBmp);
}
} catch (OutOfMemoryError e) {
Utility.displayToast(context,
getString(R.string.err_large_image));
} catch (Exception e) {
}
} else if (requestCode == UploadProfilePicActivity.REQ_CAMERA
&& data != null) {
try {
Bitmap profileBmp = (Bitmap) data.getExtras().get("data");
if (profileBmp != null) {
image.setImageBitmap(profileBmp);
}
} catch (OutOfMemoryError e) {
Utility.displayToast(context,
getString(R.string.err_large_image));
} catch (Exception e) {
}
}
}
使用参数requestCode和responseCode
答案 1 :(得分：0)
试试这段代码：
在xml中创建一个imageview
ImageView photoFrame;
public static final int REQ_CODE_PICK_IMAGE = 101;
添加：
photoFrame.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
try
{
Intent galleryIntent = new Intent(Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(galleryIntent, REQ_CODE_PICK_IMAGE);
}catch(Exception e)
{
e.printStackTrace();
}
}
});
添加以下代码：
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch(requestCode) {
case REQ_CODE_PICK_IMAGE:
if(resultCode == RESULT_OK)
{
Uri selectedImage = data.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(
selectedImage, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
photoPath = cursor.getString(columnIndex);
cursor.close();
photoFrame.setImageBitmap(Utils.getScaledImage(photoPath, 120, 120));
}
}
}
为Utils创建一个类，在其中添加以下代码：
public static Bitmap getScaledImage(String path, int width, int height){
try {
//decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeFile(path ,o);
//Find the correct scale value. It should be the power of 2.
final int REQUIRED_SIZE=70;
int width_tmp=o.outWidth, height_tmp=o.outHeight;
int scale=1;
while(true){
if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
break;
width_tmp/=2;
height_tmp/=2;
scale++;
}
//decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize=scale;
Bitmap scaledPhoto = BitmapFactory.decodeFile(path, o2);
scaledPhoto = Bitmap.createScaledBitmap(scaledPhoto, width, height, true);
return scaledPhoto;
}
catch (Exception e) {
e.printStackTrace();
}
return null;
}
使用此代码，您可以从图库中选择图像，并可以在Imageview上查看图像
答案 2 :(得分：0)
尝试我的工作代码，需要使用其ID
从mediastore查询图库图像@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == RESULT_OK)
{
if(requestCode == CAMERA_PIC_REQUEST)
{
loadCameraImage();
// Loading from camera is based on the intent passed
}
else if(requestCode == SELECT_PICTURE)
{
Uri currentUri = data.getData();
String realPath = getRealPathFromURI(currentUri);
// You will get the real path here then you can work with that path as normal
}
}
}
// Gets the real path from MEDIA
public String getRealPathFromURI(Uri contentUri) {
String [] proj={MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query( contentUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}