Question

我在button中有一个fragment。当fragment被调用并点击button时，我希望camera打开。我已经完成了很多教程。但我无法找到在camera中实施fragment的解决方案。

这是我的java代码camera.java：

public class camera extends Fragment {

private static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 100;
Button btnCapture;
ImageView imageView;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    final View rootView = inflater.inflate(R.layout.camera,
            container, false);
    btnCapture=(Button) rootView.findViewById(R.id.btnCapturePicture);
    //imageView = (ImageView) rootView.findViewById(R.id.imageview);

    btnCapture.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(intent,
                    CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE);

        }
    });

    return rootView;

}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE) {
        if (resultCode == Activity.RESULT_OK) {

            Bitmap bmp = (Bitmap) data.getExtras().get("data");
            ByteArrayOutputStream stream = new ByteArrayOutputStream();

            bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
            byte[] byteArray = stream.toByteArray();

            // convert byte array to Bitmap

            Bitmap bitmap = BitmapFactory.decodeByteArray(byteArray, 0,
                    byteArray.length);

            imageView.setImageBitmap(bitmap);

        }
    }
}
}

这是我的camera.xml布局：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:baselineAligned="false"
tools:context="com.example.prakash.eduqueri.fragments.camera">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:layout_gravity="center_vertical">
     <!--  Capture picture button
  -->
<Button
    android:id="@+id/btnCapturePicture"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Take a Picture"
    android:layout_gravity="center_horizontal"
    android:layout_marginBottom="10dp" />

这是我的logcat：

FATAL EXCEPTION: main
                                                                          Process: com.example.prakash.eduqueri, PID: 14511
                                                                          java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=65636, result=-1, data=Intent { act=inline-data (has extras) }} to activity {com.example.prakash.eduqueri/com.example.prakash.eduqueri.MainActivity}: java.lang.NullPointerException
                                                                              at android.app.ActivityThread.deliverResults(ActivityThread.java:3367)
                                                                              at android.app.ActivityThread.handleSendResult(ActivityThread.java:3410)
                                                                              at android.app.ActivityThread.access$1300(ActivityThread.java:141)
                                                                              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260)
                                                                              at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                              at android.os.Looper.loop(Looper.java:136)
                                                                              at android.app.ActivityThread.main(ActivityThread.java:5052)
                                                                              at java.lang.reflect.Method.invokeNative(Native Method)
                                                                              at java.lang.reflect.Method.invoke(Method.java:515)
                                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
                                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
                                                                              at dalvik.system.NativeStart.main(Native Method)
                                                                           Caused by: java.lang.NullPointerException
                                                                              at com.example.prakash.eduqueri.camera.onActivityResult(camera.java:87)
                                                                              at android.support.v4.app.FragmentActivity.onActivityResult(FragmentActivity.java:176)
                                                                              at android.app.Activity.dispatchActivityResult(Activity.java:5437)
                                                                              at android.app.ActivityThread.deliverResults(ActivityThread.java:3363)
                                                                              at android.app.ActivityThread.handleSendResult(ActivityThread.java:3410) 
                                                                              at android.app.ActivityThread.access$1300(ActivityThread.java:141) 
                                                                              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260) 
                                                                              at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                              at android.os.Looper.loop(Looper.java:136) 
                                                                              at android.app.ActivityThread.main(ActivityThread.java:5052) 
                                                                              at java.lang.reflect.Method.invokeNative(Native Method) 
                                                                              at java.lang.reflect.Method.invoke(Method.java:515) 
                                                                              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
                                                                              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609) 
                                                                              at dalvik.system.NativeStart.main(Native Method)

new logcat：

Unable to decode stream: java.io.FileNotFoundException: /external/images/media/24097: open failed: ENOENT (No such file or directory)

04-12 12：43：02.688 29890-29890 / com.example.prakash.eduqueri I / Adreno-EGL :: EGL 1.4 QUALCOMM build：AU_LINUX_ANDROID_LNX.LA.3.5.2.2.2_RB1.04.04.04.154.004_msm8226_LNX。 LA.3.5.2.2.2_RB1__release_AU（） OpenGL ES着色器编译器版本：E031.24.00.15 建造日期：2014年6月8日星期三当地分公司：mybranch4057433 远程分支：quic / LNX.LA.3.5.2.2.2_rb1 本地补丁：无重建分支：AU_LINUX_ANDROID_LNX.LA.3.5.2.2.2_RB1.04.04.04.154.004 + NOTHING 04-12 12：43：02.848 29890-29890 / com.example.prakash.eduqueri I / Timeline：Timeline：Activity_idle id：android.os.BinderProxy@424bdc50 time：262597724

Answer 1

如果当前片段在另一个片段内且片段在活动内部，则首先需要在父片段或活动中定义onActivityResult，然后首先在父片段和父Activty中定义onResultActivity。我猜是很可能（因为你正在使用viewPager）你的片段在一些片段内，而那个父片段在一个活动中，所以按照以下步骤：

首先在Activity中定义onActivityResult，然后在片段中定义你正在使用相机意图的片段。

root父Activity中的onActivityResult。

    @Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
}

}

在子片段中：

  @Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    for (Fragment fragment : getChildFragmentManager().getFragments()) {
        fragment.onActivityResult(requestCode, resultCode, data);
    }    super.onActivityResult(requestCode, resultCode, data);
}

注意：如果你的相机意图片段在这个频段内，那么只有你必须这样做才能跳过这一步。

现在终于在cameraIntent片段中实现onActivityResult：

@Override
public void onActivityResult(int requestCode, int resultCode, final Intent intent) {
    super.onActivityResult(requestCode, resultCode, intent);
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
        if (resultCode == HomeActivity.RESULT_OK) {
try{
           BitmapFactory.Options options = new BitmapFactory.Options();

        // downsizing image as it throws OutOfMemory Exception for larger
        // images
        options.inSampleSize = 8;
        final Bitmap bitmap = BitmapFactory.decodeFile(fileUri.getPath(),
                options);

        imageView.setImageBitmap(bitmap); } catch (NullPointerException e) {
        e.printStackTrace();
    }           }
        } else if (resultCode == HomeActivity.RESULT_CANCELED) {
            // user cancelled Image capture
            Toast.makeText(getActivity(),
                    "User cancelled image capture", Toast.LENGTH_SHORT)
                    .show();
        } else {
            // failed to capture image
            Toast.makeText(getActivity(),
                    "Sorry! Failed to capture image", Toast.LENGTH_SHORT)
                    .show();
        }
}

当相机意图开始时，在onClick of按钮中初始化fileUri变量。

最后，在启动相机意图时，您必须使用getParentFragment().startActivityForResult(intent,yourrequestCode);

所以你的明星意图如下：

  btnCapture.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {

        String fileName = System.currentTimeMillis()+".jpg";
    ContentValues values = new ContentValues();
    values.put(MediaStore.Images.Media.TITLE, fileName);
    fileUri = getActivity().getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);

    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
        getParentFragment().startActivityForResult(intent,
                CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE);

    }
});

在上面的方法中，fileUri是一个String类型变量，在方法之外定义，因为它应该用于设置图像的预览，如onActivityResult（）

所示

希望这会有所帮助，如果你有任何问题做评论，我会帮助你:) Have a happy codeing :)

Answer 2

试试这个，

点击按钮添加此代码。

int TAKE_OR_PICK = 1;
                    Intent takePictureIntent = new Intent(
                            MediaStore.ACTION_IMAGE_CAPTURE);
                    if (takePictureIntent.resolveActivity(getActivity().getPackageManager()) != null) {
                        startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
                    }

覆盖onActivityResult

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {

    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == getActivity().RESULT_OK && null != data  && TAKE_OR_PICK == 1) {
        imageView = (ImageView) findViewById(R.id.imageView1);
        Bitmap photo = (Bitmap) data.getExtras().get("data");
        imageView.setImageBitmap(photo)
if (imageBitmap != null) {
            try {
                long fileName = System.currentTimeMillis();
                File outputFile = new File(Environment.getExternalStorageDirectory(), "photo_" + fileName + ".jpg");
                FileOutputStream fileOutputStream = new FileOutputStream(outputFile);
                imageBitmap=Bitmap.createScaledBitmap(imageBitmap, 300, 300, true);
                imageBitmap.compress(Bitmap.CompressFormat.JPEG, 75, fileOutputStream);
                fileOutputStream.flush();
                fileOutputStream.close();
                File imageFile = new File(Environment.getExternalStorageDirectory() +File.separator + "photo_" + fileName + ".jpg");
                picturePath = imageFile.getPath();
                System.out.println("FILE PATH -> "+picturePath);
            }catch (Exception e) {
                e.printStackTrace();
                Toast.makeText(getActivity(), "Something went wrong", Toast.LENGTH_SHORT).show();
            }

        }
    }
}

如何在android中的片段中实现相机功能？

2 个答案: