Question

我想从imageView创建一个位图，但我首先需要在转换位图之前旋转我的imageView。我使用以下代码将imageView转换为Bitmap。

 BitmapDrawable drawable = (BitmapDrawable) imgPhoto.getDrawable();
 Bitmap photo = drawable.getBitmap();

imageView实现了一个旋转手势。我希望能够旋转imageView，然后使用旋转的imageView创建一个位图。但是，似乎我的Bitmap仍然是原始的imageView而不是旋转的位置。以下是完整的代码。谢谢。

 public class MainActivity extends AppCompatActivity implements RotationGestureDetector.OnRotationGestureListener{

private ImageView imgPhoto, imgBackground, imgCombine;
private RotationGestureDetector mRotationDetector;
private Button btnCombine;
private float angle;

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

    mRotationDetector = new RotationGestureDetector(this);

    imgPhoto = (ImageView) findViewById(R.id.imgPhoto);
    imgBackground = (ImageView) findViewById(R.id.imgBackground);
    collageImage = (ImageView) findViewById(R.id.imgCombine);

    btnCombine = (Button)findViewById(R.id.btnCombineImage);
    btnCombine.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            BitmapDrawable drawable = (BitmapDrawable) imgPhoto.getDrawable();
            Bitmap photo = drawable.getBitmap();

        }
    });
}

@Override
public boolean onTouchEvent(MotionEvent event){
    mRotationDetector.onTouchEvent(event);
    return super.onTouchEvent(event);
}

@Override
public void OnRotation(RotationGestureDetector rotationDetector) {
    angle = rotationDetector.getAngle();
    Log.d("RotationGestureDetector", "Rotation: " + Float.toString(angle));
    imgPhoto.setRotation(imgPhoto.getRotation() + (-angle));
}

 }

Answer 1

在onClick之后尝试使用此代码。它应该提供一个指定角度的旋转位图。

Matrix matrix = new Matrix();
matrix.postRotate(angle);
Bitmap rotatedPhoto = Bitmap.createBitmap(photo, 0, 0, photo.getWidth(), photo.getHeight(), matrix, true);

Answer 2

旋转ImageView：

Studio does not have write access to /private/var/folders/8c/3ffqd8814c37fw3197jq6k0r0000gn/T/AppTranslocation/FA3D0850-457F-489F-BA09-221516148C30/d/Android Studio.app/Contents. Please run it by a privileged user to update.

来源：https://stackoverflow.com/a/10104318/7639113

然后，您可以使用DrawingCache

创建位图

Matrix matrix = new Matrix();
imageView.setScaleType(ImageView.ScaleType.MATRIX);   //required
matrix.postRotate((float) angle, pivotX, pivotY);
imageView.setImageMatrix(matrix);

Answer 3

旋转效果实际上是在“画布”级别上应用的。因此，您可以做的就是获取当前的Canvas增强，然后将更改后的位图绘制到新的位图中。

if( align_mode == 1 ){
        for( int i = 0 ; i < n_1 ; i++ ){
            for( int j = 0 ; j < n_2 ; j++ ){
                d_2 = pow( vStruct1[i]->R[0] - vStruct2[j]->R_sup[0], 2 ) + pow( vStruct1[i]->R[1] - vStruct2[j]->R_sup[1], 2 ) + pow( vStruct1[i]->R[2] - vStruct2[j]->R_sup[2], 2 );
                score[i+1][j+1] = 1 / ( 1 + d_2 / d0_2 );               
            }
        }
    }

旋转后Android ImageView到Bitmap

3 个答案: