sorry i am a java newbie, i need to use camera from class extending LinearLayout.

public class ImagePicker extends LinearLayout {

...

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

                    Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                    try{
                        startActivityForResult(takePhotoIntent, REQUEST_TAKE_PHOTO);
                    }catch (ActivityNotFoundException e){
                        e.printStackTrace();
                    }
                }
            });

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

these methods need a class extending Activity. how can i use them correctly? Thanks

CodePudding user response：

There are (at least) two options to achieve this:

• you can get the activity from the ImagePicker as described in stackoverflow.com/a/32973351/3738870. However, this approach is less clean because the Intent is sent in ImagePicker but the result still has to be received in onActivityResult in the Activity. It's better to receive the result in the same class from where you requested it.
• the other approach is exposing the button and then calling the setOnClickListener on it in the Activity. Here's some sample code that demonstrates how to do this:

ImagePicker:

    public class ImagePicker extends LinearLayout {
    
        private Button button;
    
        public ImagePicker(Context context, @Nullable AttributeSet attrs) {
            super(context, attrs);
            View.inflate(context, R.layout.image_picker, this);
            button = findViewById(R.id.button);
        }
    
        public Button getButton() {
            return button;
        }
    }

Activity:

    public class Activity extends AppCompatActivity {
    
        private static int REQUEST_TAKE_PHOTO = 99;
    
        @Override
        public void onCreate(@Nullable Bundle savedInstanceState, @Nullable PersistableBundle persistentState) {
            super.onCreate(savedInstanceState, persistentState);
            setContentView(R.layout.activity_main2);
    
            ImagePicker imagePicker = findViewById(R.id.imagePicker);
            imagePicker.getButton().setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
    
                    Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                    try{
                        startActivityForResult(takePhotoIntent, REQUEST_TAKE_PHOTO);
                    }catch (ActivityNotFoundException e){
                        e.printStackTrace();
                    }
                }
            });
        }
    
        @Override
        public void onActivityResult(int requestCode, int resultCode, Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
        }
    }

An even simpler solution is to just get the Button directly in the Activity:

public class Activity extends AppCompatActivity {

    private static int REQUEST_TAKE_PHOTO = 99;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState, @Nullable PersistableBundle persistentState) {
        super.onCreate(savedInstanceState, persistentState);
        setContentView(R.layout.activity_main2);

        Button button = findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                Intent takePhotoIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                try{
                    startActivityForResult(takePhotoIntent, REQUEST_TAKE_PHOTO);
                }catch (ActivityNotFoundException e){
                    e.printStackTrace();
                }
            }
        });
    }

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