I am trying to, somewhat clone the design of an activity from a set of slides on Android UI design. However I am having a problem with a very simple task.
I have created the layout as shown in the image, and the header is a TextView
in a RelativeLayout
. Now I wish to change the background colour of the RelativeLayout
, however I cannot seem to figure out how.
I know I can set the android:background
property in the RelativeLayout
tag in the XML file, but what do I set it to? I want to define a new colour that I can use in multiple places. Is it a drawable
or a string
?
Additionally I would expect there to be a very simple way to this from within the Eclipse Android UI designer that I must be missing?
I am a bit frustrated currently, as this should be an activity that is performed with a few clicks at maximum. So any help is very appreciated. :)
This question is related to
android
android-layout
user-experience
adt
The above answers are nice.You can also go like this programmatically if you want
First, your layout should have an ID. Add it by writing following +id
line in res/layout/*.xml
<RelativeLayout ...
...
android:id="@+id/your_layout_id"
...
</RelativeLayout>
Then, in your Java code, make following changes.
RelativeLayout rl = (RelativeLayout)findViewById(R.id.your_layout_id);
rl.setBackgroundColor(Color.RED);
apart from this, if you have the color defined in colors.xml, then also you can do programmatically :
rl.setBackgroundColor(ContextCompat.getColor(getContext(), R.color.red));
If you want to change a color quickly (and you don't have Hex numbers memorized) android has a few preset colors you can access like this:
android:background="@android:color/black"
There are 15 colors you can choose from which is nice for testing things out quickly, and you don't need to set up additional files.
Setting up a values/colors.xml file and using straight Hex like explained above will still work.
The answers above all are static. I thought I would provide a dynamic answer. The two files that will need to be in sync are the relative foo.xml
with the layout and activity_bar.java
which corresponds to the Java class corresponding to this R.layout.foo
.
In foo.xml
set an id for the entire layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout android:id="@+id/foo" .../>
And in activity_bar.java
set the color in the onCreate()
:
public class activity_bar extends AppCompatActivty {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.foo);
//Set an id to the layout
RelativeLayout currentLayout =
(RelativeLayout) findViewById(R.id.foo);
currentLayout.setBackgroundColor(Color.RED);
...
}
...
}
I hope this helps.
The
res/values/colors.xml.
<color name="red">#ffff0000</color>
android:background="@color/red"
example didn't work for me, but the
android:background="#(hexidecimal here without these parenthesis)"
worked for me in the relative layout element as an attribute.
You can use android:background="#DC143C"
, or any other RGB values for your color. I have no problem using it this way, as stated here
Kotlin
linearLayout.setBackgroundColor(Color.rgb(0xf4,0x43,0x36))
or
<color name="newColor">#f44336</color>
-
linearLayout.setBackgroundColor(ContextCompat.getColor(vista.context, R.color.newColor))
4 possible ways, use one you need.
val ll = findViewById<LinearLayout>(R.id.your_layout_id)
ll.setBackgroundColor(ContextCompat.getColor(this, R.color.white))
<LinearLayout
android:background="@{@color/white}"
OR more useful statement-
<LinearLayout
android:background="@{model.colorResId}"
<LinearLayout
android:background="#FFFFFF"
<LinearLayout
android:background="@color/white"
LinearLayout ll = (LinearLayout) findViewById(R.id.your_layout_id);
ll.setBackgroundColor(ContextCompat.getColor(this, R.color.white));
Source: Stackoverflow.com