I have an ExpandableListView (ELV) with the groups having LinearLayout. I have set the height of the group to some value (38dip in this case, equivalent to two lines of text). If the group heading is long and would take more than 2 lines, it is not shown properly in the ELV item - some part of the view gets scrolled. On the other hand, if I change android:layout_height to "wrap_content" in the LinearLayout, the groups always show all the lines. But the line widths are variable, i.e., short titles show up with only 1 line and long titles show up with 2, 3 or 4 lines. That looks ugly. I would like to implement the height to be something like max("38dip", "wrap_content"). Is there a way to do this?
Even programmatically, I do not seem to be getting the actual height of the group if I set android:layout_height to "wrap_content". Any suggestions there?
Could not solve the problem directly. Added the following to the xml layout file of the group:
android:paddingTop="7dip"
android:paddingBottom="7dip"
That makes the layout looking much less congested which is what I wanted to do in the first place. Moving on - but would be interested if someone else have a better solution.
Related
i am getting "Set android:baselineAligned="false" on this element for better performance" while using LinearLayout, I know its regarding performance,but i dont know exactly why it is,please clarify me
If you are looking for a visual explanation like me, then you might find this useful.
When baselineAlign is enabled(i.e if it is set to true), then all the text in that line will be aligned to have the same baseline.
Note: By default, baselineAligned is set to true. (i.e. baselineAligned=true)
When you make baselineAligned=false, all it needs to do is to add new elements to the linear layout and be done with it. The app need not worry about where the baseline of other elements in the layout is.
See the image below for more clarity
android:baselineAligned/setBaselineAligned(boolean): When set to false,
prevents the layout from aligning its children's baselines.
So can take example with linear layout with horizontal child views having multiple TextView with different text size or different views like button there basealignment would be different and you cannot adjust it to have same basealignment if you set it to false
Reference
Update:
By setting android:baselineAligned="false" , you're preventing the extra work your app's layout has to do in order to Align its children's baselines; which can obviously increase the performance. (Less unnecessary operations on UI => Better performance) as mentioned here
I have a recyclerview with bunch of textview each as an item as you see in picture below. (Blue lines aren't really there, i added them so you can see each item separately) as you can see everything seems nice and user will not notice the text is separated.
The problem is when user increases the line space(a typical option in app) line height gets bigger except the first and last line of each item and the result seems like second picture.
My question is how to find appropriate padding to set to each item so every line height seen exactly the same?
BTW i can not use just one textview for many reason!
You can increase the divider height of your listview according to linespacing height.
Or you can set an invisible view at the bottom of every row item and increase the height of this view according to linespacing height.
Or you can set padding at the bottom of every row item and increase the value of this padding according to linespacing height.
just add some padding to the parent of your textview in the layout file of your list item .
for example the layout with linearlayout would be like :
<LinearLayout ........
paddingTop=15dp>
<TextView
..........>
</TextView>
</LinearLayout>
and you could adjust the padding dynamically if you want.
I am using TableLayout within a ListView. The data I'm presenting is tabular in nature and the TableLayout seems like a good way to ensure that the columns line up as desired. This approach worked well most of the time - see below.
Desired view:
But occasionally the Views representing the columns wrapped their text content as shown below.
After searching around for a while, I came across the following discussion on the Android Google Group. In response, I set android:stretchColumns="*" in the TableLayout and voila, the contained TextViews stopped mysteriously wrapping their text.
Here's a partial content of the layout's XML, with the change highlighted with a comment:
<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:stretchColumns="*"> <!-- stretchColumns needed to prevent
TableLayout from unilaterally deciding to shrink the column
width and thereby causing text to wrap. -->
While I'm now getting the desired result, I'm a bit confused as to why this "fixed" my problem. The TableLayout documentation states that "The width of a column is defined by the row with the widest cell in that column." But if that's true, why did the columns apparently shrink in size in the first place causing the text to wrap?
Does anyone have a good explanation?
Containers query their children for how much space they want, and this process continues recursively. Any dynamically sized layout framework is going to work this way. From the inside out, children report up to their parents their desired size, and then on a second pass the parents report back to their children how much space is available to them. When they're not included in the stretchColumns list (either explicitly by position, or implicitly by wildcard as in the example), they ask for the bare minimum which in the case of TextView is the minimum space required to display the text wrapped. When they're included in the stretchColumns list, they report the width required to display the entire contents, and if it fits they don't get wrapped. Anyone who requests more space than is available to them gets wrapped text. I imagine the priority is given in order from least space required up to the most so if you have stretchColumns="*" the largest blocks of text are getting wrapped first (if necessary) and everyone else gets to be displayed normally.
Setting two or more elements of a linear layout the same height seems to be a great problem.
I want to set four buttons in a row to the same height.
android:layout_height="wrap_content" does it for the moment but when the text on one of the buttons is longer than one line this button is increased and therefore bigger than the other ones. Due to different localisations I don't know, when and which button may have a second line.
So my idea is, to set the parent linearlayout to android:layout_height="wrap_content" and all (!) child heights to android:layout_height="fill_parent".
This works (all buttons have the same size), but I'm not sure if this causes any other problems? Because it the parent gets it's height from the childs and vice-versa.
In theory what you are describing should not work ("Because it the parent gets it's height from the childs and vice-versa".) However, we made it work in LinearLayout because it was a very common use case. I recently added similar support to FrameLayout (this feature should be part of Honeycomb.) What you are doing is therefore perfectly valid and will work just fine.
That doesn't make sense :(
Why don't you use android:singleLine="true" and some ellipsode?
Is there a way to declare a row of buttons in XML so that all the buttons have the same width, which is equal to the wrap_content width of the widest button? I'm familiar with the trick of setting all the widths to 0 and assign them all a weight of 1, but that won't work if the parent layout width is set to wrap_content. I don't want to set the parent width to fill_parent because I don't want the buttons stretched more than necessary.
The only way I can think of doing this is in code (either with onMeasure logic in each button that communicates with the other buttons or with a custom layout class).
I think you'd have to do this in code.
Creating a custom layout class would be the way to go. Override onMeasure() and make it look something like this:
Call setLayoutParams on all children to set their layout_widths to WRAP_CONTENT.
Call super.onMeasure()
Iterate child views to find the one with the biggest getMeasuredWidth().
Iterate all other child views calling setLayoutParams() with the widest pixel width.
Call super.onMeasure() again. :)
That should work but I won't stake my reputation on it... happy to help you further if it doesn't.
To get the buttons in a row in the XML you need to add the buttons with in a LinearLayout and change the orietnation to horizontal i.e.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
</LinearLayout>
As for getting the widest button and changing all the other buttons to match I am not sure as a guess you would have to have some sort of method within your activity to get the widest button and then programaticaly set all the other buttons to be the same.
Just find out what your widest button is, but it in a view with a horizontal width to match, and then use layout_width="match_parent" or "fill_parent" in < 2.3.
It'll make them all use the width assigned.
If you want to do it programatically, you need to iterate over all the sections, find the max, than iterate again and set it.