在布局中旋转ImageView...如何实现?

3

我有一个包含图像的布局(嵌入在ImageView中)。我需要将图像旋转90度逆时针方向。

我编写了一个动画代码来实现图像旋转...:

public class MainActivity extends Activity
{
    private ImageView mImageView = null;
    private Animation mRotateAnimation = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        mImageView = (ImageView) findViewById(R.id.my_image);
        mRotateAnimation = AnimationUtils.loadAnimation(this, R.anim.my_rotate_90);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            mImageView.startAnimation(mRotateAnimation);
            return true;
        }
        return super.onTouchEvent(event);
    }
}

图像平滑旋转90度,但然后又弹回到原来的状态。这是Android文档中说动画完成后会发生的事情。可以假定在通知动画结束后,需要转换ImageView(或其下层的drawable),并可能使其无效以触发重绘。
一切都很好,除了我找不到方法去做它,也找不到其他人做过的例子。
我尝试使用mImageView上的getImageMatix/setImageMatrix,但似乎没有效果。有一些Drawable的子类可以旋转图像,但是ImageView上没有setDrawable()方法,所以我不知道如何使用它。
我搜索了示例;虽然其中几个涉及动画和旋转(特别是LunarLander),但没有一个在动画一个ImageView,然后将其留在某个变换状态。
肯定我错过了什么简单的东西...啊啊啊,如何在布局内旋转ImageView?
谢谢。

我应该补充说明,90度只是一个好的圆整数例子。旋转可以是任意角度,因此“对每个图像制作四个版本:0度、90度、180度和270度旋转”不会成为一个解决方案... - Scott Smith
2个回答

2

ImageView的setImageDrawable方法将配置Image中的drawable。这应该允许您使用ImageView类,从而在其上使用Matrix函数。


0

你可以试试这个MultiTouchImageView,我用过感觉很好。

public class MultiTouchImageView extends ImageView implements OnTouchListener{

float[] lastEvent = null;
float d = 0f;
float newRot = 0f;
public static String fileNAME;
public static int framePos = 0;
//private ImageView view;
private boolean isZoomAndRotate;
private boolean isOutSide;
// 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;

private PointF start = new PointF();
private PointF mid = new PointF();
float oldDist = 1f;
public MultiTouchImageView(Context context) {
    super(context);
}


public MultiTouchImageView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}


public MultiTouchImageView(Context context, AttributeSet attrs) {
    super(context, attrs);
}


@SuppressWarnings("deprecation")
@Override
public boolean onTouch(View v, MotionEvent event) {
    //view = (ImageView) v;
    bringToFront();
    // 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) {
            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:
        isZoomAndRotate = false;
    case MotionEvent.ACTION_OUTSIDE:
        isOutSide = true;
        mode = NONE;
        lastEvent = null;
    case MotionEvent.ACTION_POINTER_UP:
        mode = NONE;
        lastEvent = null;
        break;
    case MotionEvent.ACTION_MOVE:
        if(!isOutSide){
            if (mode == DRAG && !isZoomAndRotate) {
                isZoomAndRotate = false;
                setTranslationX((event.getX() - start.x) + getTranslationX());
                setTranslationY((event.getY() - start.y) + getTranslationY());
            } else if (mode == ZOOM && event.getPointerCount() == 2) {
                isZoomAndRotate = true;
                boolean isZoom = false;
                if(!isRotate(event)){
                    float newDist = spacing(event);
                    if (newDist > 10f) {
                        float scale = newDist / oldDist * getScaleX();
                        setScaleX(scale);
                        setScaleY(scale);
                        isZoom = true;
                    }
                }
                else if(!isZoom){
                    newRot = rotation(event);
                    setRotation((float)(getRotation() + (newRot - d)));
                }
            }
        }

        break;
    }
    new GestureDetector(new MyGestureDectore());
    Constants.currentSticker = this;
    return true;
}
private class MyGestureDectore extends GestureDetector.SimpleOnGestureListener{

    @Override
    public boolean onDoubleTap(MotionEvent e) {
        bringToFront();
        return false;
    }

    @Override
    public boolean onDoubleTapEvent(MotionEvent e) {
        return false;
    }

}
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);
}

private boolean isRotate(MotionEvent event){
    int dx1 = (int) (event.getX(0) - lastEvent[0]);
    int dy1 = (int) (event.getY(0) - lastEvent[2]);
    int dx2 = (int) (event.getX(1) - lastEvent[1]);
    int dy2 = (int) (event.getY(1) - lastEvent[3]);
    Log.d("dx1 ", ""+ dx1);
    Log.d("dx2 ", "" + dx2);
    Log.d("dy1 ", "" + dy1);
    Log.d("dy2 ", "" + dy2);
    //pointer 1
    if(Math.abs(dx1) > Math.abs(dy1) && Math.abs(dx2) > Math.abs(dy2)) {
        if(dx1 >= 2.0 && dx2 <=  -2.0){
            Log.d("first pointer ", "right");
            return true;
        }
        else if(dx1 <= -2.0 && dx2 >= 2.0){
            Log.d("first pointer ", "left");
            return true;
        }
    }
    else {
         if(dy1 >= 2.0 && dy2 <=  -2.0){
                Log.d("seccond pointer ", "top");
                return true;
            }
            else if(dy1 <= -2.0 && dy2 >= 2.0){
                Log.d("second pointer ", "bottom");
                return true; 
            }

    }

    return false;
}
}

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