Question

我必须在Android设备上触摸多个手指（2个或更多）时旋转图像。如果有人有解决方案，请帮助我。我得到了一个解决方案，但它对于单指Touch来说效果非常好。 Here is the link

请帮助我，我确实。 :( :(

Answer 1

尝试使用以下代码为我工作。

float[] lastEvent = null;
float d = 0f;
float newRot = 0f;
private Matrix matrix = new Matrix();
private Matrix savedMatrix = new Matrix();
public static String fileNAME;
public static int framePos = 0;

private float scale = 0;
private float newDist = 0;

// Fields
private String TAG = this.getClass().getSimpleName();

// We can be in one of these 3 states
private static final int NONE = 0;
private static final int DRAG = 1;
private static final int ZOOM = 2;
private int mode = NONE;

// Remember some things for zooming
private PointF start = new PointF();
private PointF mid = new PointF();
float oldDist = 1f;

 public boolean onTouch(View v, MotionEvent event) {
            ImageView view = (ImageView) v;

            // Handle touch events here...
            switch (event.getAction() & MotionEvent.ACTION_MASK) {
            case MotionEvent.ACTION_DOWN:
                savedMatrix.set(matrix);
                start.set(event.getX(), event.getY());
                mode = DRAG;
                lastEvent = null;
                break;
            case MotionEvent.ACTION_POINTER_DOWN:
                oldDist = spacing(event);
                if (oldDist > 10f) {
                    savedMatrix.set(matrix);
                    midPoint(mid, event);
                    mode = ZOOM;
                }
                lastEvent = new float[4];
                lastEvent[0] = event.getX(0);
                lastEvent[1] = event.getX(1);
                lastEvent[2] = event.getY(0);
                lastEvent[3] = event.getY(1);
                d = rotation(event);
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_POINTER_UP:
                mode = NONE;
                lastEvent = null;
                break;
            case MotionEvent.ACTION_MOVE:
                if (mode == DRAG) {
                    // ...
                    matrix.set(savedMatrix);
                    matrix.postTranslate(event.getX() - start.x, event.getY()
                            - start.y);
                } else if (mode == ZOOM && event.getPointerCount() == 2) {
                    float newDist = spacing(event);
                    matrix.set(savedMatrix);
                    if (newDist > 10f) {
                        float scale = newDist / oldDist;
                        matrix.postScale(scale, scale, mid.x, mid.y);
                    }
                    if (lastEvent != null) {
                        newRot = rotation(event);
                        float r = newRot - d;
                        matrix.postRotate(r, view.getMeasuredWidth() / 2,
                                view.getMeasuredHeight() / 2);
                    }
                }
                break;
            }

            view.setImageMatrix(matrix);

            return true;
        }

//用于多点触控旋转图像。

private float rotation(MotionEvent event) {
        double delta_x = (event.getX(0) - event.getX(1));
        double delta_y = (event.getY(0) - event.getY(1));
        double radians = Math.atan2(delta_y, delta_x);

        return (float) Math.toDegrees(radians);
    }
private float spacing(MotionEvent event) {
        float x = event.getX(0) - event.getX(1);
        float y = event.getY(0) - event.getY(1);
        return FloatMath.sqrt(x * x + y * y);
    }

private void midPoint(PointF point, MotionEvent event) {
        float x = event.getX(0) + event.getX(1);
        float y = event.getY(0) + event.getY(1);
        point.set(x / 2, y / 2);
    }

Answer 2

使用matrix.postRotate(DEGREE)

bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(),bitmap.getHeight(), matrix, true);

然后将此位图设置为图像视图。

Answer 3

大家好，我得到了最好的解决方案。click Here to see。在此链接中，您将获得功能（a）拖动（b）缩放（c）旋转。您可以根据需要通过编辑此示例的代码，在代码中使用其中的任何一个或其中的任何一个。祝你好运:)）

如何在Android中触摸多个（2个以上）手指时顺时针和逆时针旋转图像？

3 个答案: