我正在开发一个应用程序，其中有一个功能是通过拖动其右下角按钮来调整和旋转imageview。
我看到了一个应用程序，它有一个特性，如果我们对角线拖动底部右侧按钮，则imageview大小会被调整，否则如果我们向左或向右方向拖动按钮，则imageview会按照方向旋转。 我希望在我的应用程序中实现这个功能。
我正在努力实现单手指旋转以及调整imageview的大小。
请指导我正确的方法。
我正在尝试此代码，并尝试应用缩放和旋转，但无法实现，请帮助我。 下面是基于手指操作缩放和旋转的代码。
public class ScaleActivity extends Activity {
ViewGroup lLayout;
static ImageView img, backgrndImg;
Canvas mCanvas;
float d;
private float mAspectQuotient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lLayout = (FrameLayout) findViewById(R.id.lLayout);
final CropView cv = new CropView(this);
lLayout.addView(cv);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public class CropView extends ImageView {
private static final int SELECTION_RECT_PAINT_COLOR = 0xFF000000;
private static final int SELECTION_RECT_FILL_COLOR = 0x70FFFFFF;
private static final int TOUCH_TOLERANCE = 25;
private static final int xInc = 25;
private static final int yInc = 25;
Paint paint = new Paint();
private int initial_size = 200;
private Point leftTop, rightBottom, center, previous, currentPoint,
rectPos;
private Paint fillPaint;
private Paint rectPaint;
protected Rect selection, dest;
private boolean isAffectedBottom = false;
Bitmap bitmap, backgroundBitmap;
Rect rectf;
Rect knobRect;
private Context mContext;
int width, height;
private Matrix matrix = new Matrix();
Bitmap resizedBitmap;
// Adding parent class constructors
public CropView(Context context) {
super(context);
mContext = context;
backgroundBitmap = BitmapFactory.decodeResource(getContext()
.getResources(), R.drawable.toast_bkgrd);
bitmap = BitmapFactory.decodeResource(getContext().getResources(),
R.drawable.aviary_adjust_knob);
rectPaint = new Paint();
rectPaint.setStyle(Style.STROKE);
rectPaint.setColor(SELECTION_RECT_PAINT_COLOR);
fillPaint = new Paint();
fillPaint.setStyle(Style.FILL);
fillPaint.setColor(SELECTION_RECT_FILL_COLOR);
currentPoint = new Point(getWidth() / 2, getHeight() / 2);
width = backgroundBitmap.getWidth();
height = backgroundBitmap.getHeight();
initCropView();
}
public CropView(Context context, AttributeSet attrs) {
super(context, attrs, 0);
initCropView();
}
public CropView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initCropView();
}
@SuppressLint("DrawAllocation")
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
mCanvas = canvas;
if (leftTop.equals(0, 0))
resetPoints();
mCanvas.save();
resizedBitmap = Bitmap.createBitmap(backgroundBitmap, 0, 0,
backgroundBitmap.getWidth(), backgroundBitmap.getHeight(),
matrix, true);
// mCanvas.drawBitmap(backgroundBitmap, matrix, rectPaint);
mCanvas.drawBitmap(resizedBitmap, null, selection, rectPaint);
mCanvas.drawBitmap(bitmap, selection.right - 25,
selection.bottom - 25, null);
rectPos.set(selection.left, selection.top);
mCanvas.restore();
}
@Override
public boolean onTouchEvent(MotionEvent event) {
int eventaction = event.getAction();
switch (eventaction) {
case MotionEvent.ACTION_DOWN:
touchDown((int) event.getX(), (int) event.getY());
previous.set((int) event.getX(), (int) event.getY());
break;
case MotionEvent.ACTION_MOVE:
touchMove((int) event.getX(), (int) event.getY());
if (isActionInsideRectangle(event.getX(), event.getY())
&& !isAffectedBottom) {
drag((int) event.getX(), (int) event.getY());
invalidate(); // redraw rectangle
previous.set((int) event.getX(), (int) event.getY());
}
previous.set((int) event.getX(), (int) event.getY());
break;
case MotionEvent.ACTION_UP:
touchUp((int) event.getX(), (int) event.getY());
previous = new Point();
break;
}
return true;
}
private void initCropView() {
paint.setColor(Color.WHITE);
paint.setStyle(Style.STROKE);
paint.setStrokeWidth(5);
leftTop = new Point();
rightBottom = new Point();
center = new Point();
previous = new Point();
rectPos = new Point();
}
public void resetPoints() {
center.set(getWidth() / 2, getHeight() / 2);
leftTop.set((getWidth() - initial_size) / 2,
(getHeight() - initial_size) / 2);
rightBottom.set(leftTop.x + initial_size, leftTop.y + initial_size);
selection = new Rect(leftTop.x, leftTop.y, rightBottom.x,
rightBottom.y);
knobRect = new Rect(selection.right, selection.bottom,
bitmap.getWidth(), bitmap.getHeight());
dest = selection;
}
private boolean isActionInsideRectangle(float x, float y) {
int buffer = 10;
return (x >= (selection.left) && x <= (selection.right)
&& y >= (selection.top) && y <= (selection.bottom)) ? true
: false;
}
void touchDown(int x, int y) {
System.out.println("selection " + selection);
int dx = (previous.x - x) / 2;
int dy = (previous.y - y) / 2;
// d= rotation(dx,dy);
currentPoint.set(x, y);
if (pointsAreClose(x, y, selection.right, selection.bottom)) {
isAffectedBottom = true;
System.out.println("isAffectedBottom " + isAffectedBottom);
}
}
void touchMove(int x, int y) {
currentPoint.set(x, y);
if (isAffectedBottom) {
int dx = (previous.x - x) / 2;
int dy = (previous.y - y) / 2;
double startAngle = getAngle(previous.x, previous.y);
double currentAngle = getAngle(x, y);
matrix.postRotate((float) (startAngle - currentAngle),
selection.width() / 2.0f, selection.height() / 2.0f);
// selection.inset(dx, dy);
invalidate();
}
}
void touchUp(int x, int y) {
currentPoint.set(x, y);
isAffectedBottom = false;
}
private boolean pointsAreClose(float x1, float y1, float x2, float y2) {
return Math.hypot(x1 - x2, y1 - y2) < TOUCH_TOLERANCE;
}
private void drag(int x, int y) {
int movement;
movement = x - previous.x;
int movementY = y - previous.y;
selection.set(selection.left + movement, selection.top + movementY,
selection.right + movement, selection.bottom + movementY);
selection.sort();
invalidate();
}
/**
* Calculate the degree to be rotated by.
*
* @param event
* @return Degrees
*/
// private float rotation(float dx, float dy) {
//
// // double delta_x = (dx);
// // double delta_y = (dy);
// double radians = Math.atan2((selection.left) - (previous.y),
// (selection.top) - (previous.x));
// double radians2 = Math.atan2((selection.left) - (dy),
// (selection.top) - (dx));
//
// System.out.println("radians" + radians);
// System.out.println("" + radians2);
// System.out.println("radians2-radians" + (radians2 - radians));
// System.out.println(Math.toDegrees(radians2 - radians));
// return (float) Math.toDegrees(radians2 - radians);
//
// }
private double getAngle(double xTouch, double yTouch) {
double x = xTouch - (getWidth() / 2d);
double y = getHeight() - yTouch - (getHeight() / 2d);
switch (getQuadrant(x, y)) {
case 1:
System.out.println("1");
return Math.asin(y / Math.hypot(x, y)) * 180 / Math.PI;
case 2:
case 3:
System.out.println("32");
return 180 - (Math.asin(y / Math.hypot(x, y)) * 180 / Math.PI);
case 4:
System.out.println("4");
return 360 + Math.asin(y / Math.hypot(x, y)) * 180 / Math.PI;
default:
// ignore, does not happen
return 0;
}
}
/**
* @return The selected quadrant.
*/
private int getQuadrant(double x, double y) {
if (x >= 0) {
return y >= 0 ? 1 : 4;
} else {
return y >= 0 ? 2 : 3;
}
}
}
}
