I have a RelativeLayout as root element. There are three LinearLayouts under root element. First and last has fixed height and the middle one takes rest of screen.
There are two ScrollViews inside the middle LinearLayout. I programatically add new views in them. I want to show three item in a scrollview no matter the screen size is.
The problem is, I can't calculate the height of are so I can't divide it by three and get item height required.
I tried to call measure() and getMeasuredHeight() but LinearLayout returned 21 (which I have no idea why) and ScrollViews returned 0. Both LinearLayout and ScrollViews has match_parent attribute.
So how can I get the actual height? I know it is calculated somewhere because I can see it covers the all empty area.
The Good
Don't unless you have a really good reason. This kind of layout won't work for tablets and larger devices (it will look very odd having giant list items) and it is not common behaviour.
The Bad
You said the top and bottom views have a fixed size, and you can get the height of the screen with:
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
// Use getSize on API13+
int displayHeight = display.getHeight();
Then the height of each row is just
int listHeight = displayHeight - (2 * fixedHeight)
int rowHeight = listHeight/3;
This is bad because it will not work in more complex layouts.
The Ugly
In onCreate the size of your views will not yet have been initialised. You need wait until the view has been given a size. There a few ways you could do this:
Use a View.OnLayoutChangeListener (API 11+)
Use a ViewTreeObserver.OnGlobalLayoutListener (API 1+)
Create a custom View class (subclass LinearLayout) and override onSizeChanged
Related
I have a ScrollView with a LinearLayout with 3 elements inside. I would like that the first element has a height of 1/3 the height of the device height and the other 2 with wrap_content, is this possible to do in xml or how would you do this? Using weight alone it does not seem possible because the LinearLayout inside the ScrollView could be longer than the device's height.
According to Android docs, android:layout_weight:
Indicates how much of the extra space in the LinearLayout is allocated to the view associated with these LayoutParams. Specify 0 if the view should not be stretched. Otherwise the extra pixels will be pro-rated among all views whose weight is greater than 0.
This implies that the weight is not dependent on the screen height, but rather only on its parent view, so you can't achieve that from xml. To achieve this I would compute the height of the screen and then resize the view:
Display screen = getWindowManager().getDefaultDisplay();
Point size = new Point();
screen.getSize(size);
int screenHeight = size.y;
myView.setLayoutParams(new LayoutParams(myView.getWidth(), screenHeight / 3));
You can give the first linear layout weight=0.333 with height=0 and the other two layout wrap_content
I'm wondering whether there is a way to find out the space available for Views within a layout.
To be a little more precise: in the activity two TextViews are displayed side by side. As the second one contains pretty much text, I'd like to check, whether this text can be displayed on the screen or whether it's too large. If that's the case I'll display a smaller version of the text instead (as Android doesn't display this text on multiple lines by default).
Currently I'm using some code like this:
WindowManager windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
Display display = windowManager.getDefaultDisplay();
Point screenSize = new Point();
display.getSize(screenSize);
int screenWidth = screenSize.x;
if (tvTitle.getWidth() + tvDescription.getWidth() > screenWidth) {
tvDescrition.setText(getString(R.string.descritption_short));
}
But this doesn't work: the widths normally are smaller than the screen, so the long version is used. But: the text isn't displayed completely, the last words are always missing.
I guess the problem is, that the layout is using a padding and is therefore reducing the space really available.
So how to fix this? Any ideas are extremely welcome :-)
You can measure the width of a text(String) in pixels. Using this method:
Paint.measureText(titleString + descriptionString);
If that exceeds the total screen width - horizontal margin - horizontal padding then you can go for the short description.
I am using a relative layout with 4 buttons (in the center, one below the other).
My problem is to adjust the gap between all buttons so it will be the same between all buttons.
I want to do it dynamically according to the height of the screen (i use Display class to get the actual height).
what is the best way to do it?
Thanks,
Amigal
You can do this via modifying the LayoutParams of your View
Button b;// your button
RelativeLayout.LayoutParams lp=(RelativeLayout.LayoutParams)b.getLayoutParams();
lp.leftMargin=10;//your left margin here
lp.topMargin=10;//your top margin here and do this for other 2 margins if you need to
sometimes you need to call
b.setLayoutParams(lp);
to have the changes applied
also i dont know how you get the screen dimensions, but this works at every API:
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
I have a bunch of images with different sizes. Each of them should be presented on the top part of the screen and must take the space in height equal to 60% of screen height. Width of the image will be dependent on it's height to save initial proportions. I tried to use weightsum property in layout and weight property in ImageView, but I don't know what to put in the height property of my image view. If it is "wrap_content", every image resizes my ImageView and all mark-up crushes.
Any advices?
If you want, you can set the image's dimensions by code.
Just set the width with the weight_sum method and then do something like:
WindowManager manager = (WindowManager) context.getSystemService(Activity.WINDOW_SERVICE);
int screenHeight = manager.getDefaultDisplay().getHeight();
YOUR_VIEW.getLayoutParams().height = (int) (screenWidth * 0.6);
Please mind that you can do so only AFTER your ImageView has been drawn on screen - so calling it within the onCreate() method will not work.
You can either call it delayed (postDelayed) or set a layout listener to one of your view.
Hope this helps.
Hi I am trying yo get the screen size of screen minus the menu bar at the bottom.
I know I could just subtract a constant number according to the resolution of the device but it is a super ugly hack. I am sure google people are not dumb enough to forget to give the user a function to get the height of the bottom menu bar so I can subtract it from the full screen size
This is a similar post.
Size of android notification bar and title bar?
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
what_i_need =metrics.heightPixels-buttomMenuHeight();
I need buttomMenuHeight();
i could not find it in the API. I don't really care about the backward comparability at this point
Thanks
Why not use the height of the activity's top-level View? e.g. if your activity contains a full-height LinearLayout, use its height, so you don't have to know the menu height, or noticiation bar height.
I think you're treading a dangerous road doing this kind of calculation, as you don't know what the future layouts for Android might be, or how they might differ on Google TV, or whatever.
Try calling getHeight() after onLayout. The view is not sized on inflate.
EDIT:
Or since Activity does not have onLayout you might wait for onSizeChanged.
(Reference How to know when activity is laid out?)
I am drawing image in native code and I need to pass the size of the screen to C.
I tried to get the Height by getHeight() of the view but that returns 0 always even after setContentView is called.
RelativeLayout masterLayout = new RelativeLayout(this);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.FILL_PARENT);
masterLayout.setLayoutParams(params);
setContentView(masterLayout);
when I try masterLayout.getHeight(), it returns 0.
I expected to get the full screen height as I said fill_parent.