Selector on background color of TextView
AndroidAndroid Problem Overview
I'm attempting to change the background color of an Android TextView
widget when the user touches it. I've created a selector for that purpose, which is stored in res/color/selector.xml
and roughly looks like that:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:state_pressed="true"
android:color="@color/semitransparent_white"
/>
<item
android:color="@color/transparent"
/>
</selector>
The clickable
attribute of the TextView
is true
, in case that's of interest.
When I assign this selector to a TextView
as android:background="@color/selector"
, I'm getting the following exception at runtime:
> ERROR/AndroidRuntime(13130): Caused by: org.xmlpull.v1.XmlPullParserException: Binary XML file line #6:
When I change the attribute to drawable, it works, but the result is looking completely wrong because the IDs appear to be interpreted as image references instead of color references (as the "drawable" suggests).
What confuses me is that I can set a color reference, e.g. "@color/black", as the background attribute directly. This is working as expected. Using selectors doesn't work.
I can also use the selector as the textColor
without problems.
What's the correct way to apply a background-color-selector to a TextView
in Android?
Android Solutions
Solution 1 - Android
The problem here is that you cannot define the background color using a color selector, you need a drawable selector. So, the necessary changes would look like this:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:state_pressed="true"
android:drawable="@drawable/selected_state" />
</selector>
You would also need to move that resource to the drawable
directory where it would make more sense since it's not a color selector per se.
Then you would have to create the res/drawable/selected_state.xml
file like this:
<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="@color/semitransparent_white" />
</shape>
and finally, you would use it like this:
android:background="@drawable/selector"
Note: the reason why the OP was getting an image resource drawn is probably because he tried to just reference his resource that was still in the color directory but using @drawable
so he ended up with an ID collision, selecting the wrong resource.
Hope this can still help someone even if the OP probably has, I hope, solved his problem by now.
Solution 2 - Android
Benoit's solution works, but you really don't need to incur the overhead to draw a shape. Since colors can be drawables, just define a color in a /res/values/colors.xml file:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="semitransparent_white">#77ffffff</color>
</resources>
And then use as such in your selector:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:state_pressed="true"
android:drawable="@color/semitransparent_white" />
</selector>
Solution 3 - Android
An even simpler solution to the above:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true">
<color android:color="@color/semitransparent_white" />
</item>
<item>
<color android:color="@color/transparent" />
</item>
</selector>
Save that in the drawable folder and you're good to go.
Solution 4 - Android
Even this works.
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:drawable="@color/dim_orange_btn_pressed" />
<item android:state_focused="true" android:drawable="@color/dim_orange_btn_pressed" />
<item android:drawable="@android:color/white" />
</selector>
I added the android:drawable
attribute to each item, and their values are colors.
By the way, why do they say that color
is one of the attributes of selector
? They don't write that android:drawable
is required.
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
<item
android:color="hex_color"
android:state_pressed=["true" | "false"]
android:state_focused=["true" | "false"]
android:state_selected=["true" | "false"]
android:state_checkable=["true" | "false"]
android:state_checked=["true" | "false"]
android:state_enabled=["true" | "false"]
android:state_window_focused=["true" | "false"] />
</selector>
Solution 5 - Android
For who is searching to do it without creating a background sector, just add those lines to the TextView
android:background="?android:attr/selectableItemBackground"
android:clickable="true"
Also to make it selectable use:
android:textIsSelectable="true"