How can I go about writing expression for font size, top, height, width... with TSS in appcelerator alloy project
'.myLabel': {
backgroundColor: '#fff',
height: Ti.Platform.displayCaps.platformHeight / 2,
width: (Ti.Platform.displayCaps.platformWidth + 50) / 2
}
You can't do calculations like this in TSS. You would do that in your controller and assign the value to each element OR use a global variable in alloy.js where you do the calculation and assign that variable. Have a look at this blog post:
https://www.tidev.io/2014/10/22/how-to-use-expressions-in-tss/
Related
I'm creating a simple card that contains a long description.
I want to set the normal height of the card to 50px and when the user clicks on it I want to expand the card to be able to fit all the content inside.
So far, to obtain my needs I wrote this:
String aLotOfText = "When Gradle resolves the compile classpath, it first resolves the runtime classpath and uses the result to determine what versions of dependencies should be added to the compile classpath. In other words, the runtime classpath determines the required version numbers for identical dependencies on downstream classpaths. Your app's runtime classpath also determines the version numbers that Gradle requires for matching dependencies in the runtime classpath for the app's test APK. The hierarchy of classpaths is described in figure 1.";
bool cardExpanded = false;
InkWell(
onTap: () {
expandCard();
},
child: AnimatedContainer(
height: cardExpanded ? null : 50,
duration: Duration(milliseconds: 200),
child: Card(
child: Text(aLotOfText),
),
)
)
expandCard() {
setState(() {
cardExpanded = !cardExpanded;
});
}
As you can see on the line height: cardExpanded ? null : 50, when cardExpanded is true I didn't specify the height, so in this way I'm able to expand the card to the right height to contain the text.
But with this little hack I've completely lost the animation and as long as this card would go in a listview with 20 or more other cards, the opening and closing makes the list to jump up and down.
I'm sure that there is a way to expand the card to the right height keeping also the animation.
I would also like to specify that the one above is just an example, in my card, there will be images and buttons as well.
In addition, when the card is opened with a button, I could add some text, so the card has to expand as well when it is opened.
That's why I cannot specify a height.
EDIT
With height: cardExpanded ? null : 50 I get what I want, so, the card grows big enough to fit the content, but as you can see there is no animation there
Instead if I provide a value like height: cardExpanded ? 100 : 50, I get the animation, but obviously the card grows until it gets to 100 pixels and it dosen't show all the content.
The result that I would like to obtain is what there is in the first example plus the animation.
Thankyou
You could set two variables:
height = MediaQuery.of(context).size.height * 0.8; //the percentage you want the card to grow
width = MediaQuery.of(context).size.width * 0.8;
So when expanded is true, the container grows.
height: cardExpanded ? height : 50,
width: cardExpanded ? width : 50,
Also, to specify how the animation will perform, you have a property that can make the animation look smoother.
curve: Curves.bounceInOut,
or you could try using a widget like expanded to adjust.
It seems like the height and fixedBarHeight cant both be used in a rowChart. Ids like to use fixedBarHeight so all the bars have the size I want, and the chart to be in a scrollable div so that the numbers of bars define the height of the chart. Is this possible?
#ialarmedalien made this block, which introduces a dc.axisChart to separate the axis of the row chart from the actual chart.
Then you can use conventional overflow-y: auto on the row chart div.
Here is a related issue on dc.js.
The dc.axis addon mentioned by #Gordon will solve the problem with the axis in a scrollable div, but not the problem asked. By default, the axis will only appear at the bottom, not before.
To solve this, add one div after the row chart div, this div will contain a copy of the axis.
<div id='row-axis'></div>
Then initialize this axis in the javascript
dc.axisChart('#row-axis')
.margins({ left: 10, top: 0, right: 10, bottom: 10 })
.height( 50 )
.width( 300 )
.dimension( dimension )
.group( group )
.elasticX( true );
Then change the margin of the row chart to 'glue' correctly with the axis. They also must have the same width.
.width(300)
.margins({ left: 10, top: 0, right: 10, bottom: 0 })
Then , in the css
div.dc-chart {
float: none;
}
Dont forget to include overflow-y: auto for the row style. Then you get:
This however doesnt solve the gap problem if your height is too large (or too small) compared to the fixedBarHeight.
But now your margin is zero, so the proper height is easy to calculate (but you must pass the gap value, which has 5 by default). Assuming N=chart.group().all().length, then do:
.fixedBarHeight(X)
.height(X*N + gap*(N+1))
Which will give you:
Worth mentioning that at this point you dont even need the fixedBarHeight anymore. Simply setting the height using XN + gap(N+1) will result in dc auto setting this value to X.
Based on: https://bl.ocks.org/ialarmedalien/0a4bf25ffc0fb96ae569a20f91957bc1
Just add style="overflow-y: auto; height: 300px;" in your rowchart div. It should work.
I am developing an application on react-native. I have made a UI which works fine on iPhone 6 but not working fine on iPhone 5 or lower versions.
How should I fix this ?
You need to think about proportion when building your UI.
1, Use percentage(%) for width and aspectRatio for height, or vice versa.
container: {
width: "100%",
aspectRatio: 10 / 3, //height will be "30%" of your width
}
2, Use flex for the jobs percentage can't do. For example, if you have arbitrary size of items in a list and you want them to share equal sizes. Assign each of them with flex: 1
3, Use rem from EStyleSheet instead of pixels. rem is a scale fator. For example, if your rem is 2 and your “11rem” will become “11*2” = “22”. If we make rem proportion to the screen sizes, your UI will scale with any screen sizes.
//we define rem equals to the entireScreenWidth / 380
const entireScreenWidth = Dimensions.get('window').width;
EStyleSheet.build({$rem: entireScreenWidth / 380});
//how to use rem
container: {
width: "100%",
aspectRatio: 10 / 3, //height will be "30%"
padding: "8rem", //it'll scale depend on the screen sizes.
}
4, Use scrollView for contents that could potentially scale out of the boxes. For example, a TextView
5, Every time you think about using pixels, consider use rem in method 3.
For a detailed explanation, you can read the article here. 7 Tips to Develop React Native UIs For All Screen Sizes
Have you designed the app using fixed widths and heights? You should definitely use the capabilities of flexbox and try to avoid settings fixed sizes as much as possible. The flex property can be used to define how much space a <View /> should use releative to others, and the other properties on that page can be used to lay out elements in a flexible way that should give the desired results on a range of different screen sizes.
Sometimes, you may also need a <ScrollView />.
When you do need fixed sizes, you could use Dimensions.get('window').
You need to calculate sizes dynamically, relying on screen size.
import { Dimensions, StyleSheet } from 'react-native'
[...]
const { width, height } = Dimensions.get('window')
[...]
const styles = StyleSheet.create({
container: {
flex: 1.
flexDirection: 'column',
},
myView: {
width: width * 0.8, // 80% of screen's width
height: height * 0.2 // 20% of screen's height
}
})
If you are using TabbarIOS, remember that Dimensions.get('window') gives you the whole screen's height, this means that you'll have to take in account that the tabbar has fixed-height of 56.
So for example, when using TabbarIOS:
const WIDTH = Dimensions.get('window').width,
HEIGHT = Dimensions.get('window').height - 56
Then use WIDTH and HEIGHT as above.
I want to be able to do the following:
height: 25% - 5px;
Obviously when I do that I get the error:
Incompatible units: 'px' and '%'.
Sass cannot perform arithmetic on values that cannot be converted from one unit to the next. Sass has no way of knowing exactly how wide "100%" is in terms of pixels or any other unit. That's something only the browser knows.
You need to use calc() instead. Check browser compatibility on Can I use...
.foo {
height: calc(25% - 5px);
}
If your values are in variables, you may need to use interpolation turn them into strings (otherwise Sass just tries to perform arithmetic):
$a: 25%;
$b: 5px;
.foo {
width: calc(#{$a} - #{$b});
}
There is a calc function in both SCSS [compile-time] and CSS [run-time]. You're likely invoking the former instead of the latter.
For obvious reasons mixing units won't work compile-time, but will at run-time.
You can force the latter by using unquote, a SCSS function.
.selector { height: unquote("-webkit-calc(100% - 40px)"); }
$var:25%;
$foo:5px;
.selector {
height:unquote("calc( #{$var} - #{$foo} )");
}
IF you know the width of the container, you could do like this:
#container
width: #{200}px
#element
width: #{(0.25 * 200) - 5}px
I'm aware that in many cases #container could have a relative width. Then this wouldn't work.
Sorry for reviving old thread - Compass' stretch with an :after pseudo-selector might suit your purpose - eg. if you want a div to fill width from left to (50% + 10px) of screen you could use (in SASS indented syntax):
.example
background: red
+stretch(0, -10px, 0, 0)
&:after
+stretch(0, 0, 0, 50%)
content: ' '
background: blue
The :after element fills 50% to the right of .example (leaving 50% available for .example's width), then .example is stretched to that width plus 10px.
Just add the percentage value into a variable and use #{$variable}
for example
$twentyFivePercent:25%;
.selector {
height: calc(#{$twentyFivePercent} - 5px);
}
Is it possible to zoom in and zoom out in a view just like using a double tap or pinch functionality? If so can we still get the same coordinates or different coordinates after zooming in?
If I have a view of height 100 and width 100 and when I click on the end of the view it obviously returns y-position as 100.
Another question I have is after zoom using a pinch or doubletap, will it return the end y co-ordinate as 100 or will it return a different value since we zoomed-in?
If this is not possible, is there an an alternative?
Thank you.
You can add the view to a scrollView. When you've done this you can zoom in and out by pinching.
var scrollView = Titanium.UI.createScrollView({
contentWidth: 'auto',
contentHeight: 'auto',
top: 0,
bottom: 0,
showVerticalScrollIndicator: true,
showHorizontalScrollIndicator: true,
//Here you can determine the max and min zoom scale
maxZoomScale: 100,
minZoomScale: 0.1,
//With this property you can set the default zoom
zoomScale: 1
});
After you create this you can add your view to it
scrollView.add(view)
Hope this helps!
Tjeu