对“方法”的引用不明确

Question

When calling Builder() I am given the error message:

Reference to 'Builder' is ambiguous, both 'androidx.camera.core.impl.UseCaseConfig.Builder' and 'androidx.camera.core.impl.ImageOutputConfig.Builder' match

The error is produced within the startCamera() function. How would I make sure the compiler knows to use the UseCaseConfig option? Any help is appreciated, thank you for your time and help.

package com.example.atlas2.Activities.Login.UserCreation.ProfilePhotoCamerax;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.camera.core.impl.PreviewConfig;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import android.content.pm.PackageManager;
import android.graphics.Matrix;
import android.os.Bundle;
import android.util.Rational;
import android.util.Size;
import android.view.Surface;
import android.view.TextureView;
import android.widget.Toast;

import com.example.atlas2.R;

public class ProfilePhotoActivityX extends AppCompatActivity {


    private int REQUEST_CODE_PERMISSIONS = 101;
    private final String[] REQUIRED_PERMISSIONS = new String[]{"android.permission.CAMERA", 
                                                  "android.permission.WRITE_EXTERNAL_STORAGE"};
    TextureView textureView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_profile_photo_x);

        textureView = findViewById(R.id.view_finder);

        if(allPermissionsGranted()){
            startCamera(); //start camera if permission has been granted by user
        } else{
            ActivityCompat.requestPermissions(this, REQUIRED_PERMISSIONS, REQUEST_CODE_PERMISSIONS);
        }
    }

    private void startCamera() {

        Rational aspectRatio = new Rational(textureView.getWidth(), textureView.getHeight());
        Size screen = new Size(textureView.getWidth(), textureView.getHeight());

        PreviewConfig pConfig = new PreviewConfig.Builder<>();

    }

    private void updateTransform(){
        Matrix mx = new Matrix();
        float w = textureView.getMeasuredWidth();
        float h = textureView.getMeasuredHeight();

        float cX = w / 2f;
        float cY = h / 2f;

        int rotationDgr;
        int rotation = (int)textureView.getRotation();

        switch(rotation){
            case Surface.ROTATION_0:
                rotationDgr = 0;
                break;
            case Surface.ROTATION_90:
                rotationDgr = 90;
                break;
            case Surface.ROTATION_180:
                rotationDgr = 180;
                break;
            case Surface.ROTATION_270:
                rotationDgr = 270;
                break;
            default:
                return;
        }

        mx.postRotate((float)rotationDgr, cX, cY);
        textureView.setTransform(mx);
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull 
                                           int[] grantResults) {

        if(requestCode == REQUEST_CODE_PERMISSIONS){
            if(allPermissionsGranted()){
                startCamera();
            } else{
                Toast.makeText(this, "Permissions not granted by the user.", 
                               Toast.LENGTH_SHORT).show();
                finish();
            }
        }
    }

    private boolean allPermissionsGranted(){

        for(String permission : REQUIRED_PERMISSIONS){
            if(ContextCompat.checkSelfPermission(this, permission) != 
               PackageManager.PERMISSION_GRANTED){
                return false;
            }
        }
        return true;
    }
}

Answer 1

First of all - what version of CameraX are you using? The latest(at the time of writing) is alpha09(core) in which you should build your preview like this:

Preview preview = new Preview.Builder().build();

You can then easily use whichever set methods in builder for your preview configuration. The google docs are not completely updated to newest version yet so you can use the forum for help.