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Android Textview with width 0 is forcing content to disappear below it

I have a TextView whose width should not exceed the ImageView above it. Both image and text are downloaded from server and I don't know their dimensions (can't make assumptions either). I went through the logic to wrap the text content using this SO post.
Here is my layout XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/parentLL"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout android:orientation="vertical"
android:id="#+id/LL1"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView
android:id="#+id/image1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/text1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ellipsize="end"
android:width="0dp"
android:text="This is a string whose width may or may not be more than the image downloaded" />
</LinearLayout>
<TextView android:background="#android:color/holo_red_dark"
android:id="#+id/text2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="Second Text"/>
</LinearLayout>
With this code, the TextView at the end (text2) does not even show up. There are 2 solutions to this issue :
Apply android:maxLines="5" to the text1. Problem with this approach is that Text1 view would always be 5 lines high (I understand 'lines' is not a unit of height, but that's what I see visually). So if the text content is just one word, there would be a big white space below. And then text2 shows up.
Change topmost linear layout (parentLL) to RelativeLayout. text2 can then be used with alignBelow=LL1. This works as expected. But I cannot migrate the topmost view to RelativeLayout, because this view is from a library not in my control. I can only modify LL1 and it's children. Due to my code, other views below (like text2) are suffering (by not showing up).
There is a third approach for setting the textview as a compound drawable on ImageView. I guess that might work (haven't tested), but my requirement is to show the TextView if image download has failed (which can be detected only after a while). So I need to have a TextView. Also, my LinearLayout LL1 can have other children too.
I would request for some help understanding :
Why is my code not showing up the content below the textview 'text1'? With width=0 on textview it seems to set the height of the parent to be match_parent.
How is RelativeLayout able to handle this smoothly ? Can I replicate any of that behavior in TextView's onMeasure ? Assume I have callbacks to detect image has been downloaded, and I can get image width also.

I think what you are running into is a conflict of setting the width and height but not setting the layout weight, which is a key factor in how Linear Layouts work. If you add one more vertical LinearLayout in there and then move #id/text2 into it, you should be set. You'll need something like the following (obviously modified to your specs, this was just a quick test). Note my use of android:layout_weight,
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="#+id/textView3" />
</LinearLayout>
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="#+id/textView2" />
</LinearLayout>
</LinearLayout>
Which splits the screen in half vertically as shown in this picture,
Photo of resulting layout

I had to wrap the TextView in a RelativeLayout, which was wrapped by a LinearLayout. Not happy with this solution, but this is the only way for now.

Change the position of a text in android studio

I just started a programing in course in android studio using Java and XML and cant really figure out how to do a simple task. I have 3 buttons at the top of the screen, they fill up the whole width of the screen. I want to add a text below these 3 buttons, but i dont really now how to specify this. Right now i have:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:showIn="#layout/activity_main">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_send" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_textcolor" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_textsize" />
<TextView
android:text="South Africa"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
/>
</LinearLayout>
Now, the text in the text element is displayed at the right side of the screen, its barely visible. The text gets cramped up so tight that it gets misaligned verticaly. What would i do if i instead wanted the text inside the textview element to be displayed just below the 3 buttons, to the left horizontaly, like normal text?
Thank you!

Use something like this. Inside the TextView tag add:
android:layout_below="#+id/buttonid"
Obviously you have to use relative layout for using this

Here you go
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:showIn="#layout/activity_main">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/button_send" />
<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/button_textcolor" />
<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/button_textsize" />
</LinearLayout>
<TextView
android:text="South Africa"
android:layout_height="match_parent"
android:layout_width="wrap_content"
/>
</LinearLayout>

Use RelativeLayout instead of LinearLayout. There are also many other layouts you can try. Check here for the other type of available layouts.
RelativeLayout lets child views specify their position relative to the
parent view or to each other (specified by ID). So you can align two
elements by right border, or make one below another, centered in the
screen, centered left, and so on. By default, all child views are
drawn at the top-left of the layout, so you must define the position
of each view using the various layout properties available from
RelativeLayout.LayoutParams.

Height of view not calculated correctly inside a weighted layout

Hi I have found weird behaviour when trying to implement the following layout on android.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<LinearLayout
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="0.25"
android:orientation="horizontal" >
</LinearLayout>
<LinearLayout
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="0.75"
android:orientation="horizontal" >
<TextView
android:id="#+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="10dp"
android:paddingRight="15dp"
android:paddingTop="10dp"
android:paddingBottom="10dp"
android:layout_margin="20dp"
android:textColor="#android:color/black"
android:lineSpacingMultiplier="1.1" />
</LinearLayout>
</LinearLayout>
This piece of layout is supposed to generate a textview on the right that takes up 75% of the screen. But for some reason the height of the Textview is calculated as if the weight of its parent is 0. The text inside the view seems to wrap perfectly, but not the view itself.
Is this normal behaviour or how can I get the textview to display the correct height?

Firstly please indent your code properly so it is easy to read. You can do that automagically in the XML editor by pressing Ctrl + Shift + F.
Secondly if you want the LinearLayouts to be 25% wide and 75% wide but fill the whole height of the screen then you need
android:layout_height="match_parent"
Thirdly, if you want the TextView to take up 75% of the screen, then why not just assign the weight directly to that and not have it wrapped in another LinearLayout?
Lastly, with weights you dont need to make the children weights add to 1. Having
android:layout_weight="1"
and
android:layout_weight="3"
is also ok.

Android: Align one element below and in the middle of another

I have an ImageView and TextView. I want to place the TextView below the image view but with the middle of the TextView aligned with the middle of the ImageView (along the horizontal axis). If the text in the TextView changes to something much larger or smaller, the middle of the text always needs to remain aligned with the middle of the ImageView. Is this possible in xml?

Yes, you are simply looking to contain both elements in a vertical LinearLayout which has android:gravity set to center_horizontal.
Something like this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical"
... >
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
... />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
... />
</LinearLayout>
Because the TextView's width is wrap_content, setting its gravity shouldn't be necessary. I would do it just for safety (and additionally, I may set the width to match_parent as well).

You can make use of RealtiveLayout as follows..
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical"
... >
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
... />
<TextView
android:layout_below="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
/>
</RelativeLayout>
If you want your textview to be of single line only then add following properties to TextView
android:ellipsezed="end"
android:singleLine="true"
Use a given layout and add it to any of your existing layout you get result what your looking for ..
Hope this explanation works for you..

set TextView android:layout_width="fill_parent" and set android:gravity="center" in TextView.
I think it help you.
Thanks

GridLayout pushes down its children and overflow when given fill_parent for height

As it seems the GridLayout will always push its children to layout corresponding to their needs. for instance the following declaration:
<?xml version="1.0" encoding="utf-8"?>
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:columnCount="3"
android:orientation="vertical"
android:rowCount="4"
android:useDefaultMargins="true" >
...
<ImageView
android:id="#+id/main_image"
android:layout_column="1"
android:layout_columnSpan="2"
android:layout_row="3"
android:scaleType="fitStart" />
</GridLayout>
The GridLayout declares fill_parent and as such I would expect it to not overflow. The GridLayout should take the size of the parent which in this case is the window (full height). However in hierarchy viewer the GridLayout is set as Wrap_content for both vertical and horizontal.
As such the ImageView (which is a large image) or any text view will be push to fit themself and as such overflow the container.
This can be seen within the hierarchy viewer where the container grid view fits the parent:
while the image view overflow
Reading the documentation, I understand there is a need to set gravity. As far as I can try, I used all kinds of gravity options and image scaling options without much effect. Removing the margins with useDefaultMargins="false" does change the layout overflow which leads the issue towards gridlayout.
My question follows:
Is this a bug or am I using the GridLayout incorrectly
How can I force the GridLayout's children to fit their container and to fill
remaining spaces

The trick in other layouts is to give the first element an android:layout_weight="1.0" and nothing to the other elements. Why it works I have no idea, but it does. Here's a simple XML that displayed an ImageView, a TextView and a Button. Without the layout_weight parameter assigned to the ImageView the text and button were shifted down.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#color/white"
android:orientation="vertical"
android:keepScreenOn = "true" >
<ImageView
android:id="#+id/imageView_surprise"
android:layout_width="wrap_content"
android:layout_height="0dip"
android:scaleType="centerInside"
android:contentDescription="#string/accessibility_imageView_surprise"
android:layout_weight="1.0" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_gravity="bottom" >
<TextView
android:id="#+id/textView_message"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textColor="#color/black"
android:textSize="24sp"
android:gravity="center_horizontal" />
<Button
android:id="#+id/button_share"
style="#style/button_text"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
</LinearLayout>