android studio 无法在图像视图中显示图像

Question

//global variable

static final int CAMERA_REQUEST = 1;
ImageView imageview;
Bitmap bitmap;

//on create:

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

//take reference

imageview = findViewById(R.id.image_view);

//the onclick listener and the intent:

Button take_photo_btn = findViewById(R.id.photo_btn);
take_photo_btn.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(intent, CAMERA_REQUEST);
    }
});

//this is the activity for result:

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

    if (requestCode == CAMERA_REQUEST && requestCode == RESULT_OK) {
        Bundle extras = data.getExtras();
        bitmap = (Bitmap) extras.get("image");
        imageview.setImageBitmap(bitmap);
    }
}

after i take a photo i didnt see it in the image view whats is the problem?

Answer 1

If you are using Marshmallow then you have to implement Runtime Permissions for Camera using in Android.

More details go this link https://developer.android.com/training/permissions/requesting

Answer 2

Assuming that you have included the camera permission in your Manifest:

<uses-permission android:name="android.permission.CAMERA" />

Try to check if the user has already granted permission to use the camera:

if (ContextCompat.checkSelfPermission(context, Manifest.permission.CAMERA)
== PackageManager.PERMISSION_DENIED)

Then this may solve your problem in Marshmallow:

requestPermissions(activity, new String[] {Manifest.permission.CAMERA}, requestCode);

Answer 3

Ok i found the problem here:

if (requestCode == CAMERA_REQUEST && requestCode == RESULT_OK)

I need to do this:

if (requestCode == CAMERA_REQUEST && resultCode == RESULT_OK)