MotionEvent.ACTION_MOVE在Android中不起作用

Question

在我的Android应用程序中，我有裁剪图像。所以，我编写了一个扩展CropBox的{​​{1}}。我想移动并调整裁剪框的大小。我使用ImageView，但MotionEvent.ACTION_MOVE不起作用。我谷歌但我没有抓到任何东西。

Attr课程：

OnTouchListener

CropBox类：

public class Attr {

    public static final float CROP_BOX_START_X = 5;
    public static final float CROP_BOX_START_Y = 5;
    public static final float CROP_BOX_END_X = 305;
    public static final float CROP_BOX_END_Y = 105;

}

CropTestActivity类：

public class CropBox extends ImageView {

    private Paint paint = new Paint();


    public CropBox(Context context) {
        super(context);
    }

    public CropBox(Context context, AttributeSet attributeSet) {
        super(context, attributeSet);
    }


    @Override
    public void onDraw(Canvas canvas) {
        float[][] circleXY = {
            {Attr.CROP_BOX_START_X, Attr.CROP_BOX_START_Y},
            {(Attr.CROP_BOX_START_X + Attr.CROP_BOX_END_X) / 2, Attr.CROP_BOX_START_Y},
            {Attr.CROP_BOX_END_X, Attr.CROP_BOX_START_Y},
            {Attr.CROP_BOX_START_X, Attr.CROP_BOX_END_Y},
            {(Attr.CROP_BOX_START_X + Attr.CROP_BOX_END_X) / 2, Attr.CROP_BOX_END_Y},
            {Attr.CROP_BOX_END_X, Attr.CROP_BOX_END_Y},
            {Attr.CROP_BOX_START_X, (Attr.CROP_BOX_START_Y + Attr.CROP_BOX_END_Y) / 2},
            {Attr.CROP_BOX_END_X, (Attr.CROP_BOX_START_Y + Attr.CROP_BOX_END_Y) / 2}
        };
        float[][] lineXY = {
            {Attr.CROP_BOX_START_X, Attr.CROP_BOX_START_Y, Attr.CROP_BOX_END_X, Attr.CROP_BOX_START_Y},
            {Attr.CROP_BOX_START_X, Attr.CROP_BOX_END_Y, Attr.CROP_BOX_END_X, Attr.CROP_BOX_END_Y},
            {Attr.CROP_BOX_START_X, Attr.CROP_BOX_START_Y, Attr.CROP_BOX_START_X, Attr.CROP_BOX_END_Y},
            {Attr.CROP_BOX_END_X, Attr.CROP_BOX_START_Y, Attr.CROP_BOX_END_X, Attr.CROP_BOX_END_Y}
        };

        paint.setColor(Color.CYAN);
        paint.setStrokeWidth(1);

        for(int i = 0 ; i < circleXY.length ; i++)
            canvas.drawCircle(circleXY[i][0], circleXY[i][1], 5, paint);

        paint.setStrokeWidth(2);

        for(int i = 0 ; i < lineXY.length ; i++)
            canvas.drawLine(lineXY[i][0], lineXY[i][1], lineXY[i][2], lineXY[i][3], paint);
    }

}

作物类：

public class CropTestActivity extends Activity {

    private ImageView imageView;
    private CropBox cropBorder;
    private RelativeLayout relativeLayout;
    private RelativeLayout.LayoutParams layoutParams;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.crop_test_layout);
        imageView = (ImageView)findViewById(R.id.android_image);
        cropBorder = new CropBox(this);
        relativeLayout = (RelativeLayout)findViewById(R.id.crop_test_layout);
        layoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.FILL_PARENT, RelativeLayout.LayoutParams.FILL_PARENT);
        ViewTreeObserver viewTreeObserver = imageView.getViewTreeObserver();
        if(viewTreeObserver.isAlive()) {
            viewTreeObserver.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
                public void onGlobalLayout() {
                    layoutParams.leftMargin = imageView.getWidth() / 2 - (int)((Attr.CROP_BOX_START_X + Attr.CROP_BOX_END_X) / 2) + imageView.getLeft();
                    layoutParams.topMargin = imageView.getHeight() / 2 - (int)((Attr.CROP_BOX_START_Y + Attr.CROP_BOX_END_Y) / 2) + imageView.getTop();
                }
            });
        }
        relativeLayout.addView(cropBorder, layoutParams);
        cropBorder.setOnTouchListener(new Crop());
    }

}

布局XML：

public class Crop implements OnTouchListener {

    private static final int NONE = 0;
    private static final int BOX_DRAG = 1;
    private static final int BORDER_DRAG = 2;

    private Matrix matrix = new Matrix();
    private Matrix savedMatrix = new Matrix();

    private PointF start = new PointF();

    private int mode = NONE;

    private float cropBoxStartX = Attr.CROP_BOX_START_X;
    private float cropBoxStartY = Attr.CROP_BOX_START_Y;
    private float cropBoxEndX = Attr.CROP_BOX_END_X;
    private float cropBoxEndY = Attr.CROP_BOX_END_Y;

    public boolean onTouch(View view, MotionEvent event) {
        CropBox cropBox = (CropBox)view;

        switch(event.getAction() & MotionEvent.ACTION_MASK) {

            case MotionEvent.ACTION_DOWN:
                savedMatrix.set(matrix);
                start.set(event.getX(), event.getY());
                if(event.getX() > cropBoxStartX && event.getX() < cropBoxEndX && event.getY() > cropBoxStartY && event.getY() < cropBoxEndY)
                    mode = BOX_DRAG;
                else if(event.getX() == cropBoxStartX || event.getX() == cropBoxEndX || event.getY() == cropBoxStartY || event.getY() == cropBoxEndY)
                    mode = BORDER_DRAG;
                else
                    mode = NONE;
                break;

            case MotionEvent.ACTION_UP:
                mode = NONE;
                break;

            case MotionEvent.ACTION_MOVE:
                if(mode == BOX_DRAG) {
                    matrix.set(savedMatrix);
                    matrix.postTranslate(event.getX() - start.x, event.getY() - start.y);
                }
                else if(mode == BORDER_DRAG) {  
                }
                break;
        }
        cropBox.setImageMatrix(matrix);
        return true;
    }

}

感谢您的帮助。

Answer 1

我相信您的实现是正确的，我唯一没有看到的是您将CropBox的缩放类型设置为MATRIX以便能够使用setImageMatrix。