How do I make the background of a Textview
about 20% transparent (not fully transparent), where there is a color in the background (i.e. white)?
This question is related to
android
transparency
textview
Here's a programmatic solution from @Aromero's answer to calculate the hexadecimal value for the alpha channel. :)
public static void main(String[] args) throws Exception {
final Scanner scanner = new Scanner(System.in);
int transPerc;
float fPerc;
System.out.println("Enter the transparency percentage without % symbol:");
while((transPerc=scanner.nextInt())>=0 && transPerc <=100){
fPerc = (float) transPerc / 100;
transPerc = Math.round(255 * fPerc);
System.out.println("= " + Integer.toHexString(transPerc));
System.out.print("another one please : ");
}
scanner.close();
}
Use the below code for black:
<color name="black">#000000</color>
Now if I want to use opacity then you can use the below code:
<color name="black">#99000000</color> <!-- 99 is for alpha and others pairs zero's are for R G B -->
And below for opacity code: and all opacity level here
100% — FF
95% — F2
90% — E6
85% — D9
80% — CC
75% — BF
70% — B3
65% — A6
60% — 99
55% — 8C
50% — 80
45% — 73
40% — 66
35% — 59
30% — 4D
25% — 40
20% — 33
15% — 26
10% — 1A
5% — 0D
0% — 00
If you always to forget what code for transparency then you must have to see below link and no worry about to remember anything regarding transparent code :-
https://github.com/duggu-hcd/TransparentColorCode
textviewHeader.setTextColor(Color.parseColor(ColorTransparentUtils.transparentColor(R.color.border_color,10)));
I have taken three Views. In the first view I set full (no alpha) color, on the second view I set half (0.5 alpha) color, and on the third view I set light color (0.2 alpha).
You can set any color and get color with alpha by using the below code:
<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"
android:gravity = "center"
android:orientation = "vertical"
tools:context = "com.example.temp.MainActivity" >
<View
android:id = "@+id/fullColorView"
android:layout_width = "100dip"
android:layout_height = "100dip" />
<View
android:id = "@+id/halfalphaColorView"
android:layout_width = "100dip"
android:layout_height = "100dip"
android:layout_marginTop = "20dip" />
<View
android:id = "@+id/alphaColorView"
android:layout_width = "100dip"
android:layout_height = "100dip"
android:layout_marginTop = "20dip" />
</LinearLayout>
public class MainActivity extends Activity {
private View fullColorView, halfalphaColorView, alphaColorView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fullColorView = (View)findViewById(R.id.fullColorView);
halfalphaColorView = (View)findViewById(R.id.halfalphaColorView);
alphaColorView = (View)findViewById(R.id.alphaColorView);
fullColorView.setBackgroundColor(Color.BLUE);
halfalphaColorView.setBackgroundColor(getColorWithAlpha(Color.BLUE, 0.5f));
alphaColorView.setBackgroundColor(getColorWithAlpha(Color.BLUE, 0.2f));
}
private int getColorWithAlpha(int color, float ratio) {
int newColor = 0;
int alpha = Math.round(Color.alpha(color) * ratio);
int r = Color.red(color);
int g = Color.green(color);
int b = Color.blue(color);
newColor = Color.argb(alpha, r, g, b);
return newColor;
}
}
Kotlin version:
private fun getColorWithAlpha(color: Int, ratio: Float): Int {
return Color.argb(Math.round(Color.alpha(color) * ratio), Color.red(color), Color.green(color), Color.blue(color))
}
Done
I would recommend use alpha
attribute.
<TextView
android:alpha="0.8" />
Or now you can use selector
. Create background_color_25.xml
in the colors
package.
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:alpha="0.8" android:color="@color/background_color" />
</selector>
And here is usages:
<TextView
android:background="@color/background_color_25" />
There is an XML value alpha
that takes double values.
Since API 11+
the range is from 0f
to 1f
(inclusive), 0f
being transparent and 1f
being opaque:
android:alpha="0.0"
thats invisible
android:alpha="0.5"
see-through
android:alpha="1.0"
full visible
That's how it works.
I know, that's a very old question.
If you want use a color value, you can also use the short version of that with #ARGB
. Where A
is the value for the alpha channel.
In case of a white color there are the following transparency values:
#FFFF - 0%
#EFFF - 6,7%
#DFFF - 13,3%
#CFFF - 20,0%
#BFFF - 26,7%
#AFFF - 33,3%
#9FFF - 40,0%
#FFF8 - 46,7%
#7FFF - 53,3%
#6FFF - 60,0%
#5FFF - 66,7%
#4FFF - 73,3%
#3FFF - 80,0%
#2FFF - 86,7%
#1FFF - 93,3%
#0FFF - 100,0%
So you can for TextView
add the following line for 20% transparency:
<TextView
android:background="#CFFF"
... />
if you want to make color 50% transparent in kotlin,
val percentage = 50f/100 //50%
ColorUtils.setAlphaComponent(resources.getColor(R.color.whatEverColor), (percentage * 255).toInt())
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:alpha="0.9"
/>
Alpha ranges between 0(transparent) and 1(opaque) in Android API 11+
You can try to do something like:
textView.getBackground().setAlpha(51);
Here you can set the opacity between 0 (fully transparent) to 255 (completely opaque). The 51 is exactly the 20% you want.
All hex value from 100% to 0% alpha, You can set any color with alpha values mentioned below. e.g #FAFFFFFF(ARRGGBB)
100% — FF
99% — FC
98% — FA
97% — F7
96% — F5
95% — F2
94% — F0
93% — ED
92% — EB
91% — E8
90% — E6
89% — E3
88% — E0
87% — DE
86% — DB
85% — D9
84% — D6
83% — D4
82% — D1
81% — CF
80% — CC
79% — C9
78% — C7
77% — C4
76% — C2
75% — BF
74% — BD
73% — BA
72% — B8
71% — B5
70% — B3
69% — B0
68% — AD
67% — AB
66% — A8
65% — A6
64% — A3
63% — A1
62% — 9E
61% — 9C
60% — 99
59% — 96
58% — 94
57% — 91
56% — 8F
55% — 8C
54% — 8A
53% — 87
52% — 85
51% — 82
50% — 80
49% — 7D
48% — 7A
47% — 78
46% — 75
45% — 73
44% — 70
43% — 6E
42% — 6B
41% — 69
40% — 66
39% — 63
38% — 61
37% — 5E
36% — 5C
35% — 59
34% — 57
33% — 54
32% — 52
31% — 4F
30% — 4D
29% — 4A
28% — 47
27% — 45
26% — 42
25% — 40
24% — 3D
23% — 3B
22% — 38
21% — 36
20% — 33
19% — 30
18% — 2E
17% — 2B
16% — 29
15% — 26
14% — 24
13% — 21
12% — 1F
11% — 1C
10% — 1A
9% — 17
8% — 14
7% — 12
6% — 0F
5% — 0D
4% — 0A
3% — 08
2% — 05
1% — 03
0% — 00
You can manage color opacity changing the first 2 characters in the color definition:
#99000000
100% — FF
99% — FC
98% — FA
97% — F7
96% — F5
95% — F2
94% — F0
93% — ED
92% — EB
91% — E8
90% — E6
89% — E3
88% — E0
87% — DE
86% — DB
85% — D9
84% — D6
83% — D4
82% — D1
81% — CF
80% — CC
79% — C9
78% — C7
77% — C4
76% — C2
75% — BF
74% — BD
73% — BA
72% — B8
71% — B5
70% — B3
69% — B0
68% — AD
67% — AB
66% — A8
65% — A6
64% — A3
63% — A1
62% — 9E
61% — 9C
60% — 99
59% — 96
58% — 94
57% — 91
56% — 8F
55% — 8C
54% — 8A
53% — 87
52% — 85
51% — 82
50% — 80
49% — 7D
48% — 7A
47% — 78
46% — 75
45% — 73
44% — 70
43% — 6E
42% — 6B
41% — 69
40% — 66
39% — 63
38% — 61
37% — 5E
36% — 5C
35% — 59
34% — 57
33% — 54
32% — 52
31% — 4F
30% — 4D
29% — 4A
28% — 47
27% — 45
26% — 42
25% — 40
24% — 3D
23% — 3B
22% — 38
21% — 36
20% — 33
19% — 30
18% — 2E
17% — 2B
16% — 29
15% — 26
14% — 24
13% — 21
12% — 1F
11% — 1C
10% — 1A
9% — 17
8% — 14
7% — 12
6% — 0F
5% — 0D
4% — 0A
3% — 08
2% — 05
1% — 03
0% — 00
In Android Studio there is a built-in tool to adjust the color and alpha/opacity value:
Explanation with example:
https://devdeeds.com/how-to-add-custom-color-to-views-in-xml-android-studio-ide/
See Popularity below textView using this
android:alpha="0.38"
XML
android:color="#3983BE00" // Partially transparent sky blue
Dynamically
btn.getBackground().setAlpha(128); // 50% transparent
tv_name.getBackground().setAlpha(128); // 50% transparent
Where the INT ranges from 0 (fully transparent) to 255 (fully opaque).
<TextView
style="@style/TextAppearance.AppCompat.Caption"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:alpha="0.38"
android:gravity="start"
android:textStyle="bold"
tools:text="1994|EN" />
android:alpha="0.38"
Text View alpha property set 0.38 to your textView visibility is faid
We can make transparent in dis way also.
White color code - FFFFFF
20% white - #33FFFFFF
20% — 33
70% white - #B3FFFFFF
70% — B3
All teh hex value from 100% to 0%
100% — FF, 99% — FC, 98% — FA, 97% — F7, 96% — F5, 95% — F2, 94% — F0, 93% — ED, 92% — EB, 91% — E8, 90% — E6, 89% — E3, 88% — E0, 87% — DE, 86% — DB, 85% — D9, 84% — D6, 83% — D4, 82% — D1, 81% — CF, 80% — CC, 79% — C9, 78% — C7, 77% — C4, 76% — C2, 75% — BF, 74% — BD, 73% — BA, 72% — B8, 71% — B5, 70% — B3, 69% — B0, 68% — AD, 67% — AB, 66% — A8, 65% — A6, 64% — A3, 63% — A1, 62% — 9E, 61% — 9C, 60% — 99, 59% — 96, 58% — 94, 57% — 91, 56% — 8F, 55% — 8C, 54% — 8A, 53% — 87, 52% — 85, 51% — 82, 50% — 80, 49% — 7D, 48% — 7A, 47% — 78, 46% — 75, 45% — 73, 44% — 70, 43% — 6E, 42% — 6B, 41% — 69, 40% — 66, 39% — 63, 38% — 61, 37% — 5E, 36% — 5C, 35% — 59, 34% — 57, 33% — 54, 32% — 52, 31% — 4F, 30% — 4D, 29% — 4A, 28% — 47, 27% — 45, 26% — 42, 25% — 40, 24% — 3D, 23% — 3B, 22% — 38, 21% — 36, 20% — 33, 19% — 30, 18% — 2E, 17% — 2B, 16% — 29, 15% — 26, 14% — 24, 13% — 21, 12% — 1F, 11% — 1C, 10% — 1A, 9% — 17, 8% — 14, 7% — 12, 6% — 0F, 5% — 0D, 4% — 0A, 3% — 08, 2% — 05, 1% — 03, 0% — 00
Use a color with an alpha value like #33------
, and set it as background of your editText using the XML attribute android:background=" "
.
255 * 0.2 = 51 ? in hex 33
Try this code :)
Its an fully transparent hex code - "#00000000"
In Kotlin,you can use using alpha like this,
//Click on On.//
view.rel_on.setOnClickListener{
view.rel_off.alpha= 0.2F
view.rel_on.alpha= 1F
}
//Click on Off.//
view.rel_off.setOnClickListener {
view.rel_on.alpha= 0.2F
view.rel_off.alpha= 1F
}
Result is like in this screen shots.
Hope this will help you.Thanks
Source: Stackoverflow.com