Develop Reference

Different column size for a listview in Xamarin

I have a listview and each row is shown after inflating the following view. It is a LinearLayout and it works fine until I give each textview (which is a column in my list) the same size. If I change any of those width I get unexpected results. For example, if I put 0.5 to the first textView (called "test") I was expecting that textView to have much smaller size, but it is opposite. So I tried using 3, but again very unexpected behavior. So if I want the first textView to be much smaller than the other 4, how can I do that?
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="30dp"
android:paddingLeft="5dp"
android:paddingTop="2dp">
<TextView
android:text="Test"
android:layout_width="match_parent"
android:layout_weight="3"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#333333"
android:id="#+id/testView" />
<TextView
android:text="Name"
android:layout_width="match_parent"
android:layout_weight="1"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#333333"
android:id="#+id/nameView" />
<TextView
android:text="Surname"
android:layout_width="match_parent"
android:layout_weight="1"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#333333"
android:id="#+id/surnameView" />
<TextView
android:text="Age"
android:layout_width="match_parent"
android:layout_weight="1"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#333333"
android:id="#+id/ageView" />
<TextView
android:text="Profession"
android:layout_width="match_parent"
android:layout_weight="1"
android:layout_height="wrap_content"
android:gravity="center"
android:textColor="#333333"
android:id="#+id/professionView" />

If I change any of those width I get unexpected results.
The reason you get unexpected results is that you set every TextView layout_width property to match_parent. The document said that :
Child views can specify a weight value, and then any remaining space in the view group is assigned to children in the proportion of their declared weight.
We can see that the layout_widt property for every TextView in your layout should set to wrap_content. It means the width of the TextView equal to the original width (android: layout_width =warp_content) plus the proportion of the remaining space. Just like this.

Android: ImageView next to TextView not showing

I have a TextView and ImageView in a ListView row, positioned next to each other. However, the ImageView doesn't show up at all, and doesn't register clicks either. This is the XML code:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/textView"
android:text="text"
android:layout_width="320dp"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:layout_centerVertical="true"
android:padding="10dp" />
<ImageView
android:id="#+id/imageView"
android:clickable="true"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:layout_centerVertical="true"
android:layout_toRightOf="#id/textView"
android:src="#drawable/ic_action"/>
</RelativeLayout>
The problem seems to lie in the layout_toRightOf line, if I remove it, the ImageView is shown, but in the wrong place. But I don't understand why it's causing a problem. What am I missing?

The issue is that the TextView is pushing the ImageView off the screen.
You can fix this using a LinearLayout and android:layout_weight
eg:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/textView"
android:text="text"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_marginTop="10dp"
android:layout_centerVertical="true"
android:padding="10dp" />
<ImageView
android:id="#+id/imageView"
android:clickable="true"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:layout_centerVertical="true"
android:layout_toRightOf="#id/textView"
android:src="#drawable/ic_action"/>
</LinearLayout>
More info on the layout_weight attribute:
This attribute assigns an "importance" value to a view in terms of how much space it should occupy on the screen. A larger weight value allows it to expand to fill any remaining space in the parent view. Child views can specify a weight value, and then any remaining space in the view group is assigned to children in the proportion of their declared weight. Default weight is zero.
For example, if there are three text fields and two of them declare a weight of 1, while the other is given no weight, the third text field without weight will not grow and will only occupy the area required by its content. The other two will expand equally to fill the space remaining after all three fields are measured. If the third field is then given a weight of 2 (instead of 0), then it is now declared more important than both the others, so it gets half the total remaining space, while the first two share the rest equally.

You need to use LinearLayout with weight.. if you set fixed width and the size of the phone is small, it will either stretch out of the screen.
//do linearlayout with orientation horizontal
<LinearLayout
...
orientation = "horizontal"
...
>
<TextView
....
android:layout_width="0dp"
android:layout_weight="1"
...
/>
<Button
....
android:layout_width="wrap_content"
...
/>
</LinearLayout>
Play with android:layout_weight, you will understand

Android - Button text center gravity not working

I have this XML layout in my App (example of one button):
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/scrollViewMain"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffffff" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#fff0e8" >
///some views
<Button
android:id="#+id/btnVysledkySportka"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/chckSprotka"
android:layout_alignRight="#+id/chckSprotka"
android:layout_alignTop="#+id/chckSprotka"
android:layout_margin="3dp"
android:layout_toRightOf="#+id/textView3"
android:background="#ffe118"
android:gravity="center"
android:onClick="vysledkySportka"
android:text="Archiv výsledků"
android:textStyle="bold" />
///some views
</RelativeLayout>
</ScrollView>
But when I start my app at Android 4.3, the text of buttons isn´t in center of button. Look at the screenshot (in red rectangle):
Where can be problem?
EDIT:
Whole layout

When you specify:
android:layout_alignBottom="#+id/chckSprotka"
android:layout_alignRight="#+id/chckSprotka"
android:layout_alignTop="#+id/chckSprotka"
It does make the bottom/right/top edge of your button match the bottom edge of the given anchor view ID & accommodates bottom/right/top margin, but while doing that, the android_gravity does not take the resultant height/width into consideration.
So the gravity of the text is center according to wrap_content for layout_height and layout_width.
You can verify that by setting values for layout_height and layout_width (Eg. 200dp and 100dp to try with) and you will get the text with gravity center but for that height and width.
To confirm the same, what you can do is use a container LinearLayout for your Button like:
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/chckStastnych"
android:layout_alignRight="#+id/chckStastnych"
android:layout_alignTop="#+id/chckStastnych"
android:layout_margin="3dp"
android:layout_toRightOf="#+id/textView3"
android:background="#ffe118" >
<Button
android:id="#+id/btnVysledkyStastnych"
android:layout_gravity="center"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffe118"
android:gravity="center"
android:onClick="vysledkyStastnych"
android:text="Archiv výsledků"
android:textStyle="bold" />
</LinearLayout>
Set the gravity of LinearLayout as center and then center the Button within or as shown above, use layout_gravity for the button to center it in parent LinearLayout.
This will work as a solution when you do that for all 4 buttons, however there might be better options if you restructure your xml and avoid this kind of nesting.

Try This:
<Button
android:id="#+id/btnVysledkySportka"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/chckSprotka"
android:layout_alignRight="#+id/chckSprotka"
android:layout_alignTop="#+id/chckSprotka"
android:layout_margin="3dp"
android:layout_toRightOf="#+id/textView3"
android:background="#ffe118"
android:gravity="center_vertical"
android:onClick="vysledkySportka"
android:text="Archiv výsledků"
android:textStyle="bold" />

Issues with layout_toLeftOf

I have the following layout file:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:text="TOP"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<RelativeLayout
android:background="#color/azul_pressed"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="#+id/tv1"
android:paddingLeft="100dp"
android:text="|RIGHT--"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/tv2"
android:layout_toLeftOf="#id/tv1"
android:text="--LEFT|"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</RelativeLayout>
<TextView
android:text="BOTTOM"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
Which produces the following output:
This line:
android:layout_toLeftOf="#id/tv1"
causes tv2 to disapear from the screen and creates all that extra blue space.
Why?

In a relative layout you have to align you have to align your content to either the parent or to another widget.
I believe this is what you are looking for:
<TextView
android:id="#+id/tv1"
android:paddingLeft="100dp"
android:text="|RIGHT--"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#+id/tv2"/>
<TextView
android:id="#+id/tv2"
android:layout_alignParentLeft="true"
android:text="--LEFT|"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
See how I aligned tv1 to the left of the parent and then tv2 to the right of tv1.
You can also do it the other way around.

Are you confusing padding with margin? Padding will move the text around in the TextView, and isn't actually part of the boundary. Use margins instead if you want to push them from the side, or padding on the parent ViewGroup (same thing).
<TextView
android:id="#+id/tv2"
android:layout_alignParentLeft="true"
android:text="--LEFT|"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/tv1"
android:text="|RIGHT--"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#+id/tv2"/>
This will place the views right next to each other.
If you want to then offset them by 100 pixels on the left, then add:
android:margin_left="100dp" to tv2. Since tv1 is attached to the right of tv2, it will push both over by 100dp. I'm not really sure what your intentions are, but I think a LinearLayout with gravity set on the children would be better since both textviews would occupy the same amount of space and be spread out evenly.
edit: note that this is similar to Carlos Paulino's answer. I think you were confusing the padding offset of the text with the layout boundary.

How to layout view right aligned and bottom of an LinearLayout

I am trying to layout 1 textview (upText) left aligned and 1 textview (downText) and an image view (image) both on the same line and right aligned.
how can I do that? I tried that, but both 'textview' and image view at left aligned.
<TextView
android:id="#+id/uptext"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="left"/>
<TextView
android:id="#+id/downtext"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:singleLine="true"
android:gravity="right|bottom"/>
<ImageView
android:id="#+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="right|bottom"/>
</LinearLayout>

Don't use a LinearLayout. Use a RelativeLayout, with
your first TextView set with android:layout_alignParentLeft="true"
your second TextView set with android:layout_alignParentBottom="true" and android:layout_alignParentRight="true"
something similar for your ImageView, which presently looks like it is going to overlap the second TextView

I realize this post is a bit old but just in case someone comes across this in their search for clarity;
The parent linear layout is where gravity needs to be specified for the child to align with the desired behavior which is why the above posts are explaining that linear layout is not possible for two separate behaviors to occur since a child cannot decide where to align itself within a linear layout.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="200dp"
android:layout_height="50dp"
android:gravity="bottom|right">
<TextView
android:layout_width="40dp"
android:layout_height="20dp"
android:text="test"/></LinearLayout>
It should also be said that the parent linear layout must have a defined size and not be wrap-content or this will not work since wrap content implies that there will be no extra space in the layout for positioning, so at least 'match-parent' for width and height is necessary as well as having a parent with a greater size than wrap-content for the child linear layout itself.
Hope this helps.

Using RelativeLayout
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="bottom">
<TextView
android:id="#+id/text1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="hi"
android:textStyle="bold|italic"
android:gravity="right"/>
<TextView
android:id="#+id/text2"
android:layout_below="#id/text1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="All"
android:gravity="right"/>
</RelativeLayout>