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I need to make sure that horizontal recyclerView height is the same as the height of the biggest item.
Items can have a different height (Item = always the same image + title + subtitle, title and subtitle could have infinite length).
When I set wrap_content for my recyclerView it would resize, basing on the height of visible items which makes content below recyclerView jump, and that's something I want to avoid.
What I want to achieve:
The gray area is visible viewport.
So basically I would like to get somehow hight of the biggest item, then put recyclerView height to that number.
What I already tried is approximation high of items based on length of title + subtitle but it's very inaccurate because for example even if two titles have the same text length they could have different width because of font that I use which is not a monospace font.
I just had this issue as well. My solution is:
Wrap the RecyclerView inside a ConstraintLayout.
Set the ConstraintLayout's layout_height to wrap_content.
Add an item view to the ConstraintLayout and populate it with the data of the item you expect to be the highest based on the length of its title for example.
Set the item view's visibility to invisible.
Set the RecyclerView's layout_height to zero, and make its top and bottom constraints match that of the item view.
Too late for an answer, but maybe this will help someone.
I struggled with the same issue and couldn't find an acceptable solution.
Solved by following:
First, you need to override onMeasure from the RecyclerView to save the largest element height:
class CustomRecycleView(ctx: Context, attrs: AttributeSet) : RecyclerView(ctx, attrs) {
private var biggestHeight: Int = 0
override fun onMeasure(widthSpec: Int, heightSpec: Int) {
for (i in 0 until childCount) {
val child = getChildAt(i)
child.measure(widthSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED))
val h = child.measuredHeight
if (h > biggestHeight) biggestHeight = h
}
super.onMeasure(widthSpec, MeasureSpec.makeMeasureSpec(biggestHeight, MeasureSpec.EXACTLY))
}
}
In you layout replace RecycleView with this CustomRecycleView:
onMeasure is called when a new element in the list is visible, and if the element is the highest, then we save this value. For example: if the first element has lowest height but lates has highest then at start RecycleView will be have height match to first element but after scrolling it will stay match to highest.
If you don't need to make RecycleView height match to highest item at start then you can stop here.
To do this at the beginning, you must make a hack (based on #MidasLefko suggestion):
To find out initially what the height of the highest element will be, you need to add a scroll mechanism to the end and the beginning. I did it as follows:
private fun initRecycleView(items: ArrayList<Object>) {
val adapter = Adapter()
rv.visibility = View.INVISIBLE
rv.vadapter = adapter
rv.layoutManager = LinearLayoutManager(context, LinearLayoutManager.HORIZONTAL, false)
rv.setHasFixedSize(true)
rv.smoothScrollToPosition(pinnedPosts.size)
Handler().postDelayed({
rv.smoothScrollToPosition(0)
}, 300)
Handler().postDelayed({
rv.visibility = View.VISIBLE
}, 700)
}
Set the visibility of Recycle view to INVISIBLE and after 700 milliseconds to VISIBLE to make this process invisible for user. Also, scrolling to start is performed with a delay of 300 milliseconds, because without some delay it can work incorrectly. In my case, this is needed for a list of 3 elements, and these delays is optimal for me.
Also remember to remove all Handler callbacks in onStop ()
I don't think that this is possible out of the box.
Let's think for a minute about how a RecyclerView works. In order to save memory it reuses the same View objects and just binds them to new data from the list as the user scrolls. So, for example, if the user sees item's 0 and 1 then the system has only measured and laid out 2 items (and perhaps one or two more to help scroll performance).
But let's say that your tall item is number 50 in the list, when the RecyclerView binds the first few items it has no idea at all that item 50 even exists, let alone how tall it will be.
However, you can do something a bit hacky. For example, you can measure each items height after it is bound, keep track of the tallest, and then manually set the RecyclerView height to that size. With that mechanism in place you can make the RecyclerView be hidden, then manually scroll to the end of the list, scroll back to the beginning of the list, then show the RecyclerView.
Not the most elegant solution, but it should work.
Created a method to calculate the projected height of textView by trying all the description in the list to get the highest height.
public static int getHeightOfLargestDescription(final Context context, final CharSequence text, TextView textView) {
final WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
final Point displaySize = new Point();
wm.getDefaultDisplay().getSize(displaySize);
final int deviceWidth = displaySize.x;
textView.setTypeface(Typeface.DEFAULT);
textView.setText(text, TextView.BufferType.SPANNABLE);
int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(deviceWidth, View.MeasureSpec.AT_MOST);
int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
textView.measure(widthMeasureSpec, heightMeasureSpec);
return textView.getMeasuredHeight();
}
then used this method to in onCreateViewHolder to get ready with the highest height to be used while binding the view.
MyViewHolder myViewHolder = new MyViewHolder(itemView);
for (Model m : modelList) {
currentItemHeight = getHeightOfLargestDescription(context, m.description, myViewHolder.description);
if (currentItemHeight > highestHeight) {
highestHeight = currentItemHeight;
}
}
Then used this highestHeight in onBindViewHolder` to set the height of the description TexView, so that all the views always have the same height that is equal to the highest height.
viewHolder.description.setHeight(highestHeight);
Code is committed in the
https://github.com/dk19121991/HorizontalRecyclerWithDynamicHeight
Let me know if this solves your problem, if you have some more question feel free to ask.
Thanks
To view a full discussion on this solution please see below
https://stackoverflow.com/a/67403898/4828650
You may try this:
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(#NonNull RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
final int newHeight = recyclerView.getMeasuredHeight();
if (0 != newHeight && minHeight < newHeight) {
// keep track the height and prevent recycler view optimizing by resizing
minHeight = newHeight;
recyclerView.setMinimumHeight(minHeight);
}
}
});
you should try with different item_view type
Try this
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = mLayoutInflater.inflate(R.layout.view_item, parent, false);
// work here if you need to control height of your items
// keep in mind that parent is RecyclerView in this case
int height = parent.getMeasuredHeight() / 4;
itemView.setMinimumHeight(height);
return new ItemViewHolder(itemView);
}
Or you can try this also
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View itemView = inflater.inflate(R.layout.itemview, parent, false);
ViewGroup.LayoutParams layoutParams = itemView.getLayoutParams();
layoutParams.height = (int) (parent.getHeight() * 0.3);
itemView.setLayoutParams(layoutParams);
return new MyViewHolder(itemView);
}
You can also set your itemView with fixed height.
I disabled the recycling in recycler view and it solved the issue.
recyclerView.getRecycledViewPool().setMaxRecycledViews(TYPE_CAROUSEL, 0);
this solution may have a performance issue if there are a lot of items but will work fine for a few items lets say 5 to 20 which was case for me.
recyclerViewHorizontal.setMinimumHeight(maxItemHeight) has worked well for me.
The height of RecyclerView item is not fixed,i need to set the background image for every item,so I want to get the height of recyclerview's item to resize the Image,but the itemView.getHeight() always return 0 in onBindViewHolder.
I have try to search many questions or articles,but i still cant get a good soluation.
Short
Measure the View manually
view.measure(
View.MeasureSpec.makeMeasureSpec(recyclerViewWidth, View.MeasureSpec.EXACTLY),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
and get the height with view.getMeasuredHeight()
Background
A view will return a valid value for View.getHeight()only after it has been measured. The measuring itself will automatically happen by the system when the view is about to be displayed on screen.
When Android wants to display the layout, it will recursively call the view.layout() function for each view in the view tree. Each Parent tells its children the constraints they might have (width/height) and ask them to view.measure() themselves. As a result, the view will store the measured values BASED on the constraints in designated members (MeasuredHeight/Width). Note that at this point view.getMeasuredHeight() will hold the value while view.getHeight() will still be invalid. view.getHeight() will only return a valid value once the view has an actual height in the UI hierarchy.
Recap
So, to know the height of a view element, before it has been measured and laid out by the system, we will need to invoke the view.measure() function manually.
The measure function expects 2 parameters which derived from the view LayoutParams + the parent constraints.
In the above code sample, we are measuring the view forcing its width to be EXACTLY the width of the parent (the RecycleView), and the height is not limited.
I suggest that you define multiple layout files with the expected heights and inflate them according to some criteria in your data set.
ViewHolder onCreateViewHolder (ViewGroup parent, int viewType){
if(some condition){
//inflate layout 1
}else{
//inflate layout 2
}
or as answered here: you can get the measurements while initializing the view holder
itemView.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
int width = itemView.getMeasuredWidth();
int height = itemView.getMeasuredHeight();
How about this:
view.post(() -> {
int width = view.getMeasuredWidth();
int height = view.getMeasuredHeight();
}
using this code to get recycler view's item height:
view.getViewTreeObserver().addOnGlobalLayoutListener(new
ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
//don't forget remove this listener
view.getViewTreeObserver().removeOnGlobalLayoutListener(this);
//get item height here
int itemHeight = v.getHeight();
}
});
MyViewHolder.kt
With the addOnGlobalLayoutListener() method, the height value is obtained before the TextView is drawn. And then save it in a member variable.
The key is to modify the UI inside and outside the implementation of the listener so that there are no rendering problems (when the views are redrawn).
That is, you shoud use the getter inside the listener and; the setter inside and outside the listener.
companion object {
var maxHeight: Int = 0
fun create(mContext: Context): MyViewHolder {
val view = LayoutInflater.from(mContext).inflate(R.layout.item_answer, null)
updateLayout(view)
view.viewTreeObserver.addOnGlobalLayoutListener {
if (view.myTextView.height > maxHeight)
maxHeight = view.myTextView.height
updateLayout(view)
}
return MyViewHolder(mContext, view).apply {
setIsRecyclable(false)
}
}
fun updateLayout(view: View) {
if (maxHeight != 0 && view.myTextView.height != maxHeight)
view.myTextView.height = maxHeight
}
}
Source
I was wondering, how to check whether the current ScrollView is scrollable? It seems that, there isn't public method called canScroll or isScrollable in ScrollView.
Scrollable : You can move the ViewGroup inside the ScrollView up and down, and the scroll bar will be visible when you move it up and down. So, if there is only little rows in the ScrollView, and they can fit inside single screen, ScrollView is not scrollable then.
You can do some little math to calculate the views raw height and the height of the content. If the difference of this heights is < 0 the view is scrollable.
To calculate the raw height you can use View.getMeasuredHeight().
Because ScrollView is a ViewGroup and has max one child, get the height of that child with ViewGroup.getChildAt(0).getHeight();
Use a ViewTreeObserver to get the heights, because it will be called at the moment the layout / view is changing the visibility, otherwise the heights could be 0.
ScrollView scrollView = (ScrollView)findViewById(R.id...);
ViewTreeObserver observer = scrollView.getViewTreeObserver();
observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
int viewHeight = scrollView.getMeasuredHeight();
int contentHeight = scrollView.getChildAt(0).getHeight();
if(viewHeight - contentHeight < 0) {
// scrollable
}
}
});
scrollView.viewTreeObserver
.addOnGlobalLayoutListener {
val isScrollable = scrollView.canScrollVertically(1)
}
I think I might be missing something, but shouldn't it be as simple as checking if
scrollView.getHeight() >= parentView.getMeasuredHeight()
you might actually need: scrollView.getChildAt(0).getHeight() and/or parentView.getHeight() instead, but the idea is the same.
How do I compute the width and height of an inflated View if the parent is a PopupWindow, not a ViewGroup? I cannot use LayoutInflator.inflate(int resId, ViewGroup parent, attachToRoot boolean) because PopupWindow is not a ViewGroup, so I use LayoutInflator.inflate(int resId) instead, but after that I getWidth() and getHeight() return zero :(
I need to resize the PopupWindow to fit the View, but cannot do so until the View has a parent. Do I have a chicken-and-egg problem?
By the way the View is a subclass of RelativeView so calculating it manually is essentially out of the question.
Thanks in advance,
Barry
Actually popupWindow supports "wrap content" constans, so if you want popup be exact as your view - use this:
popup = new PopupWindow(context);
popup.setWidth(ViewGroup.LayoutParams.WRAP_CONTENT);
popup.setHeight(ViewGroup.LayoutParams.WRAP_CONTENT);
--other options--
getWidth() and getHeight() returns zero, because view have size only after drawing on the screen. You can try to get values from LayoutParams of inflated view.
If there is fill_parent value - you are in egg-chicken situation.
If there is values in px or dp you can manually calculate size in pixels:
Math.round(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dpSize, context.getResources().getDisplayMetrics()));
If there is wrap_content value - you can use view.measure() method - all children and view itself will be measured, and you can get view.getMeasuredHeight() and view.getMeasuredWidth().
As Jin35 said, your problem was that the view's width and height haven't been calculated yet...the dimensions aren't calculated until after the layout pass.
Using a fixed width and height from dimension resources (e.g. from a values/dimens.xml file) is one workaround, since then you don't need to wait for the view's onMeasure to occur -- you can get the value of the same dimension resource you used for the view you're interested in, and use that.
A better solution is to just delay your calculations until after the onMeasure happens. You can do that by overriding onMeasure, but a more elegant solution is to use a temporary OnGlobalLayoutListener like this:
View popup = LayoutInflator.inflate(int resId);
if(popup != null) {
// set up an observer that will be called once the listView's layout is ready
android.view.ViewTreeObserver viewTreeObserver = listView.getViewTreeObserver();
if (viewTreeObserver.isAlive()) {
viewTreeObserver.addOnGlobalLayoutListener(new android.view.ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
// This will be called once the layout is finished, prior to displaying.
View popup = findViewById(resId);
if(popup != null) {
int width = popup.getMeasuredWidth();
int height = popup.getMeasuredHeight();
// don't need the listener any more
popup.getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
}
});
}
}
Please try this:
Display display = getWindowManager().getDefaultDisplay();
Log.e("", "" + display.getHeight() + " " + display.getWidth());
I have a view made up of TableLayout, TableRow and TextView. I want it to look like a grid. I need to get the height and width of this grid. The methods getHeight() and getWidth() always return 0. This happens when I format the grid dynamically and also when I use an XML version.
How to retrieve the dimensions for a view?
Here is my test program I used in Debug to check the results:
import android.app.Activity;
import android.os.Bundle;
import android.widget.TableLayout;
import android.widget.TextView;
public class appwig extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.maindemo); //<- includes the grid called "board"
int vh = 0;
int vw = 0;
//Test-1 used the xml layout (which is displayed on the screen):
TableLayout tl = (TableLayout) findViewById(R.id.board);
tl = (TableLayout) findViewById(R.id.board);
vh = tl.getHeight(); //<- getHeight returned 0, Why?
vw = tl.getWidth(); //<- getWidth returned 0, Why?
//Test-2 used a simple dynamically generated view:
TextView tv = new TextView(this);
tv.setHeight(20);
tv.setWidth(20);
vh = tv.getHeight(); //<- getHeight returned 0, Why?
vw = tv.getWidth(); //<- getWidth returned 0, Why?
} //eof method
} //eof class
I believe the OP is long gone, but in case this answer is able to help future searchers, I thought I'd post a solution that I have found. I have added this code into my onCreate() method:
EDITED: 07/05/11 to include code from comments:
final TextView tv = (TextView)findViewById(R.id.image_test);
ViewTreeObserver vto = tv.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
LayerDrawable ld = (LayerDrawable)tv.getBackground();
ld.setLayerInset(1, 0, tv.getHeight() / 2, 0, 0);
ViewTreeObserver obs = tv.getViewTreeObserver();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
obs.removeOnGlobalLayoutListener(this);
} else {
obs.removeGlobalOnLayoutListener(this);
}
}
});
First I get a final reference to my TextView (to access in the onGlobalLayout() method). Next, I get the ViewTreeObserver from my TextView, and add an OnGlobalLayoutListener, overriding onGLobalLayout (there does not seem to be a superclass method to invoke here...) and adding my code which requires knowing the measurements of the view into this listener. All works as expected for me, so I hope that this is able to help.
I'll just add an alternative solution, override your activity's onWindowFocusChanged method and you will be able to get the values of getHeight(), getWidth() from there.
#Override
public void onWindowFocusChanged (boolean hasFocus) {
// the height will be set at this point
int height = myEverySoTallView.getMeasuredHeight();
}
You are trying to get width and height of an elements, that weren't drawn yet.
If you use debug and stop at some point, you'll see, that your device screen is still empty, that's because your elements weren't drawn yet, so you can't get width and height of something, that doesn't yet exist.
And, I might be wrong, but setWidth() is not always respected, Layout lays out it's children and decides how to measure them (calling child.measure()), so If you set setWidth(), you are not guaranteed to get this width after element will be drawn.
What you need, is to use getMeasuredWidth() (the most recent measure of your View) somewhere after the view was actually drawn.
Look into Activity lifecycle for finding the best moment.
http://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle
I believe a good practice is to use OnGlobalLayoutListener like this:
yourView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
if (!mMeasured) {
// Here your view is already layed out and measured for the first time
mMeasured = true; // Some optional flag to mark, that we already got the sizes
}
}
});
You can place this code directly in onCreate(), and it will be invoked when views will be laid out.
Use the View's post method like this
post(new Runnable() {
#Override
public void run() {
Log.d(TAG, "width " + MyView.this.getMeasuredWidth());
}
});
I tried to use onGlobalLayout() to do some custom formatting of a TextView, but as #George Bailey noticed, onGlobalLayout() is indeed called twice: once on the initial layout path, and second time after modifying the text.
View.onSizeChanged() works better for me because if I modify the text there, the method is called only once (during the layout pass). This required sub-classing of TextView, but on API Level 11+ View. addOnLayoutChangeListener() can be used to avoid sub-classing.
One more thing, in order to get correct width of the view in View.onSizeChanged(), the layout_width should be set to match_parent, not wrap_content.
Are you trying to get sizes in a constructor, or any other method that is run BEFORE you get the actual picture?
You won't be getting any dimensions before all components are actually measured (since your xml doesn't know about your display size, parents positions and whatever)
Try getting values after onSizeChanged() (though it can be called with zero), or just simply waiting when you'll get an actual image.
As F.X. mentioned, you can use an OnLayoutChangeListener to the view that you want to track itself
view.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
#Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
// Make changes
}
});
You can remove the listener in the callback if you only want the initial layout.
I guess this is what you need to look at: use onSizeChanged() of your view. Here is an EXTENDED code snippet on how to use onSizeChanged() to get your layout's or view's height and width dynamically http://syedrakibalhasan.blogspot.com/2011/02/how-to-get-width-and-height-dimensions.html
ViewTreeObserver and onWindowFocusChanged() are not so necessary at all.
If you inflate the TextView as layout and/or put some content in it and set LayoutParams then you can use getMeasuredHeight() and getMeasuredWidth().
BUT you have to be careful with LinearLayouts (maybe also other ViewGroups). The issue there is, that you can get the width and height after onWindowFocusChanged() but if you try to add some views in it, then you can't get that information until everything have been drawn. I was trying to add multiple TextViews to LinearLayouts to mimic a FlowLayout (wrapping style) and so couldn't use Listeners. Once the process is started, it should continue synchronously. So in such case, you might want to keep the width in a variable to use it later, as during adding views to layout, you might need it.
Even though the proposed solution works, it might not be the best solution for every case because based on the documentation for ViewTreeObserver.OnGlobalLayoutListener
Interface definition for a callback to be invoked when the global layout state or the visibility of views within the view tree changes.
which means it gets called many times and not always the view is measured (it has its height and width determined)
An alternative is to use ViewTreeObserver.OnPreDrawListener which gets called only when the view is ready to be drawn and has all of its measurements.
final TextView tv = (TextView)findViewById(R.id.image_test);
ViewTreeObserver vto = tv.getViewTreeObserver();
vto.addOnPreDrawListener(new OnPreDrawListener() {
#Override
public void onPreDraw() {
tv.getViewTreeObserver().removeOnPreDrawListener(this);
// Your view will have valid height and width at this point
tv.getHeight();
tv.getWidth();
}
});
Height and width are zero because view has not been created by the time you are requesting it's height and width . One simplest solution is
view.post(new Runnable() {
#Override
public void run() {
view.getHeight(); //height is ready
view.getWidth(); //width is ready
}
});
This method is good as compared to other methods as it is short and crisp.
You should rather look at View lifecycle: http://developer.android.com/reference/android/view/View.html Generally you should not know width and height for sure until your activity comes to onResume state.
You can use a broadcast that is called in OnResume ()
For example:
int vh = 0;
int vw = 0;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.maindemo); //<- includes the grid called "board"
registerReceiver(new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
TableLayout tl = (TableLayout) findViewById(R.id.board);
tl = (TableLayout) findViewById(R.id.board);
vh = tl.getHeight();
vw = tl.getWidth();
}
}, new IntentFilter("Test"));
}
protected void onResume() {
super.onResume();
Intent it = new Intent("Test");
sendBroadcast(it);
}
You can not get the height of a view in OnCreate (), onStart (), or even in onResume () for the reason that kcoppock responded
Simple Response: This worked for me with no Problem.
It seems the key is to ensure that the View has focus before you getHeight etc. Do this by using the hasFocus() method, then using getHeight() method in that order. Just 3 lines of code required.
ImageButton myImageButton1 =(ImageButton)findViewById(R.id.imageButton1);
myImageButton1.hasFocus();
int myButtonHeight = myImageButton1.getHeight();
Log.d("Button Height: ", ""+myButtonHeight );//Not required
Hope it helps.
Use getMeasuredWidth() and getMeasuredHeight() for your view.
Developer guide: View
CORRECTION:
I found out that the above solution is terrible. Especially when your phone is slow.
And here, I found another solution:
calculate out the px value of the element, including the margins and paddings:
dp to px:
https://stackoverflow.com/a/6327095/1982712
or dimens.xml to px:
https://stackoverflow.com/a/16276351/1982712
sp to px:
https://stackoverflow.com/a/9219417/1982712 (reverse the solution)
or dimens to px:
https://stackoverflow.com/a/16276351/1982712
and that's it.