Develop Reference

Leave blank line in Linear Layout

I am developing for android. The app is designed in XML in Linear Layout. What I want to do is to leave some blank lines between the consecutive buttons/text to ensure some neatness in the GUI. Is it posible to do it in Linear Layout? Please help...

You should use margins to seperate different components in your layout. An example of how this would look in your XML is: android:layout_marginTop="12dp"

If you want to leave space outside the border of text/button and next view elements you can use android:layout_marginLeft, android:layout_marginRight, android:layout_marginTop and android:layout_marginBottom.
If you want to leave space between border of the text/button and actual content of the text/button you can use android:paddingLeft, android:paddingRight, android:paddingTop and android:paddingBottom.
For more info check out this question
how to increase the space between the elements in linearlayout in android?

Bottom margin Android LinearLayout item in XML ignored, but works in Java code

I am developing an app with an activity with member reactions on a hike event. The reactions are the yellow "balloons" which are made using a LinearLayout. Each item is constructed from a XML file (listitem_deelnemerreactie.xml) which defines the layout for a reaction item. The top level of this layout file is a LinearLayout my itself.
I want some spacing between the separate elements, as well as some right margin. The most straightforward way to so this should be: setting a bottom and right margin on the top-level LinearLAyout element of the listitem_deelnemerreactie.xml layout file.
But setting the bottom margin on the LinearLayout has no effect on the vertical spacing, though the right margin does have an effect.
The only way to be able to set a vertical margin appears to be: setting is in the Java code, after attaching the inflated view to the container.
See the two images for the effect and the code.
Though setting the margins in the code is a working workaround, I still think it is strange this cannot be achieved in the XML. Why is the bottom margin attribute ignored while the right margin is not?
Any ideas?

Have you tried to set an android:padding="10dp" for example on your elements to spaced them ?

Removing the margin from bottom in android Relativelayout

Hello i have used a Relativelayout in android using XML but when i see image in graphical layout there is small margin left at bottom in different screensizes.How to remove that margin.I also used a ScrollView in layout.

I think you have to set bottom margin in negative
like
android:layout_marginBottom="-10dip"

Check whether you have used padding for your layout,
Better post your layout file and/or screenshot.

disabling the Yellow-Black gradient color on scrolling at the ends of listview, scrollview, horizontal scroll view

We know that, when we scroll a listview at bottom or top of the list, we will see gradient color of yellow and black. Same thing will happen for ScrollView and HorizontalScrollView also at the edges. I want to disable the color when user scrolling these views.
is it possible to disable that color as we disable scrollbars with property
android:scrollbars="none"
If anybody know the solution please help me.

The yellow-black gradient color is actually appears when you over scroll the scroll views.
It can be eliminated by using below code in XML file of ScrollView or HorizontalScrollView
android:overScrollMode="never"
It will work for android 2.3 and above. I don't for below API levels.

Use android:fadingEdge="none" in <ListView>

How do I layout a button bar with buttons of different heights?

How do I go about implementing a button bar with buttons of different shapes and heights? As an example (please excuse my poor drawing skills for this quick mockup):
The example bar has 3 buttons, with the middle button (3) a different shape and height than the other 2 buttons (1,2). The button bar will be a view that is included and merged into other views so as to seem to float on top of the parent view.
I was thinking of implementing buttons 1 and 2 into a layout, and then button 3 as another layout that I then merge with the first two button's layout.

like my previous comrades said, you need some kind of layout or container that can have a background (if you wish for button #3 to hoover above it) then use relative layout for mixing the two the disadvantage of this other than complexity is that youcannot relate to the other two buttons since they reside in a different layout.
More elegant solution may be to have a special background drawable that can:
have a method setCurrentHeight() that will specify the height the actual viewable section should have the rest will be filled with transparent color.
override it's own draw so just before it's drawing it will have a callback called, call back you can register yourself to.
then you can register the callback in your activity to take the current position of the #3 button and set the height accordingly, this way you are still with one layout with special drawable as background.
A customized LevelDrawable might do the trick.

I would layout this bar as follows:
A RelativeLayout as a container for the rest, with height set to wrap_content and alignparentbottom = true
An ImageView for the bar
2 Buttons with a transparent background (Button 1 and 2)
Button 3 is a custom Button with a custom Image of a trapezoid as background
So you will have a Layout similar to this:
<RelativeLayout
...>
<ImageView
.../>
<Button
... Button 1 />
<Button
... Button 2 />
<Button
... Button 3 />
</RelativeLayout>

I don't exactly know that this will work, and I can't test it, but you might give something like this a try; I believe it can all be done elegantly through XML.
Have a RelativeLayout (id:mainLayout) that will contain all of your views, wrap_content for both dimensions.
Have a blank View as your first child that will serve as your background bar
Set the View's background color/image to what you want; layout_width to fill_parent; layout_height to wrap_content; layout_alignTop="#id/leftButton"; layout_alignBottom="#id/leftButton".
Add an ImageButton for your center button (id:bigButton), wrap_content for both dimensions; layout_centerInParent="true".
Add an ImageButton for your left button (id:leftButton), wrap_content for both dimensions; layout_toLeftOf="#id/bigButton"; layout_centerInParent="true".
Add an ImageButton for your right button (id:rightButton), wrap_content for both dimensions; layout_toRightOf="#id/bigButton"; layout_centerInParent="true".
In my head, I believe this works, but I could be off. Regardless, something to think about, and I hope it helps you find a solution. :)

Better you can tablelayout with different button styles or relative layout for button "3"