I have an image view which is contained within a relative layout. I am trying to get the screen y coordinates of the top of the image view and the screen y coordinates of the bottom of the image view. I have tried this:
float yMin = (float)levelH.getTop();
float yMax = (float)levelH.getBottom();
float yMin seems almost correct. I am translating another image view (IM2) up and down this image view(IM1). So I am trying to set a limit on how far (IM2) can translate up and down. So my thinking was to get the y top and bottom of (IM1) I can set those as max and min.
Anyone know how to do this?
ps Im using android accelometer to move (IM2)
getTop() ansd getBottom() look at coordinates within it's parent. To get coordinates of it's position on the screen you can use getLocationOnScreen
Use it like this:
int[] coords = {0,0};
view.getLocationOnScreen(coords);
int absoluteTop = coords[1];
int absoluteBottom = coords[1] + view.getHeight();
Use View.getLocationOnScreen() and/or getLocationInWindow()
Related
I have tried various methods but I want to get bitmap's coordinates when the activity loads so that I can use it to set polygon view.
I have tried using the imageview width and height but the polygon views occupy all of the screen I want the polygon view to be restricted to bit map for that I need the bitmap coordinates.
I want the (x,y) coordinates which are written in blue as depicted below.any help would be appreciated.the image
If I understood you Q correctly then you need a mathematical sol here to get x,y positions. 1st use bitmap to be set as ImageView.ScaleType= CENTER_INSIDE.
So, your image position is fixed & will touch either X or Y axis.
Calculate ratios:
Br(BitmapRatio) = Bw (bitmapWidth) / Bh (bitmapHeight)
Ir(ImageViewRatio) = Iw / Ih
Now, use below formula:
if(Ir > Br) {
y = 0;
x = Br*Ih/2;
} else {
x = 0;
y = (Iw/Br)/2;
}
I have a simple drawing app where I have a picture of a letter in the back filling an ImageView set to 45% of the screen's height. I have a JSON file that stores points along the letter. I'm trying to display those points on top of the picture of the letter.
Those points' coordinates range between y = -440 and y = 200. In order to properly display the points I need the top and the height of the imageView containing the letter to map the points onto the screen. I have to map the points to the proper points in runtime because with different screen sizes need different scale to display the points properly.
This is what it should look like (this is with a phone specific correction factor):
This is what it actually looks like:
I render the drawing via a Canvas that I paint the points onto. I'm pretty sure the problem lies in how I'm getting the top of the ImageView.
Here's what I've tried:
//1
float y = view.getTop();
//2
final int[] screenPos = new int[2];
iv.getLocationOnScreen(screenPos);
float y = screenPos[1];
//3
float offset = iv.getTop() - screenPos[1];
float y = iv.getTop() + offset;
Is there something I'm supposed to be doing that I'm not? Is there a better way the relative returns of getTop()? Help.
It will give you the position relative to the screen
Rect rect = new Rect();
view.getGlobalVisibleRect(rect);
float top = rect.top;
//there is also rect.bottom, rect.width, rect.height etc.
I'm trying to create the control, that allows moving view with the finger. To do this, I follow recommendations from this post.
But presented method needs some modification, to prevent my view from being moved beyond the screen. I found out how to get maxY and maxY coordinates - for my Samsung Galaxy A6 it's 1080x1920. But the problem is, that my maxY is deep beyond the visible bottom edge of the device.
So my control almost disappears, when reaches Y about 1650. What 300 more pixels go for. I can suppose, that this is NavigationBar height + my control view height, but this also doesn't place my control as expected.
I define max coordinates with this method.
private void setMaxCoordinates(int viewWidth, int viewHeight) {
Display display = getWindowManager().getDefaultDisplay();
Point displaySize = new Point();
display.getSize(displaySize);
maxX = displaySize.x - viewWidth;
maxY = displaySize.y - viewHeight;
}
Please, help me to define the correct formula to detect bottom edge coordinate.
I've found a solution. First of all I was wrong with getting bottom coordinates with the help of WindowManager. This just gives you height of your screen in pixels, that is not related to the container. So to detect your bottom coordinate this way, you have to consider:
StatusBar height.
NavigationBar height.
Height of all views that lokated higher, then your container.
Height of your own control view (ImageView in my case).
So formula will look like this.
maxY = windowHeight - (statusBarHeight + navBarheight + allUpperViewsHeight + yourViewHeight)
The correct way to define the bootom of your container, is to get the container's height and deduct your control height.
maxY = containerHeight - yourViewHeight;
I am currently working with onDraw(); and custom shapes.
What I am trying to do here is to draw 3 lines on the blue rectangle below:
And display a person's speed range settings and their current speed by drawing 3 lines. I am planning to do the speed range through getting the location, the width and the height of the rectangle and then dividing this up by the range set by the user.
However, I cannot find a resource that allows me to get the location, width and height of the blue rectangle.
Is there any way to achieve this, or do I simply have to get it from the source XML?
for getting the location of view related to parent view:
float x = view.getX();
float y = view.getY();
for getting the location of view related to Screen:
int[] location = new int[2];
view.getLocationOnScreen(location);
int x = location[0];
int y = location[1];
I have the next question:
Im developing an app that when i move a imageView and drop it, if the view drops under the half height of the screen goes to a (X,Y) position and if is over the half height screen, goes to another position.
I need to calculate the half of the screen generic, so i use the next code:
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
halfHeight = displaymetrics.heightPixels / 2;
This works great, im trying in a screen 1920x1080, the code returns 540.
But when im going to see if when i drop the view is under or over the half, here is what i dont understand. i get the Y position of the view and is ok, what i dont understand is why the Y = 0 is not on the TOP of the screen, if i move the view to the top, i get a negative Y position like -260.
Someone can explain me why this happen?
Is there i way that the (0,0) position starts in the top left of the screen?
Greets, hope you understand
If you call getX() or getY() then you are getting relative values for x and y (relative to the view that the call was dispatched from). If you call getRawX() or getRawY() it will give you the absolute position of the view relative to the device's screen.
Most likely you are getting negative values of -260 because you are dragging the ImageView 260 away from the view in which the call was made (perhaps the view on the top of the screen has a height of 260). If you are trying to use getX() or getY() to calculate the middle of the screen then you would have to take all sizes of all views into consideration but I think you want to use getRawX() and getRawY()
An angle of 0 degrees correspond to the geometric angle of 0 degrees (3 o'clock on a watch.)
try using translate to translate the co-ordinates to top of the screen.
http://developer.android.com/reference/android/graphics/Canvas.html#translate(float, float)