React native - display views with curved border between them - react-native

Any idea how can I create two views that fill the screen, with a curved border between them?
In the following example, the top one (red) should have a concave border, the other one (blue) a convex one?
Using the code suggested in the answer (60 instead of 60%, which doesn't work), gives the following:
Not what I am looking for, unfortunately...

Test this code and check out.
<View>
<View style={{width: "100%", height: 100, backgroundColor: 'skyblue'}} />
<View style={{position:"absolute",top:50,width: "100%", height: 100, backgroundColor: 'steelblue',borderRadius:"60%"}} />
<View style={{width: "100%", height: 100, backgroundColor: 'steelblue',}} />
</View>
The above code has a slight resemblence to what you want to achieve. However the best option would be to use image in the background.

Follow this answer by Vishal in another Stack question: Using SVG
RESULT:

Related

Different height of maximum and minimum track using react-native-slider

At this moment the library https://www.npmjs.com/package/#miblanchard/react-native-slider does not have a solution to be able to change the height of the left and right track of the thumb.
How to implement it?
I found a workaround:
The container in which the Slider is should have overflow style: "hidden"
I use renderThumbComponent to display the thumb left line to the left
renderThumbComponent={() => (
<>
<View style={styles.thickerLine} />
<View style={styles.thumb} />
</>
)}
I set the style for thickerLine to be as long as possible, so that it goes beyond the container.
thickerLine: {
position: "absolute",
top: 8,
right: 0,
backgroundColor: "blue",
height: 4,
width: window.width,
},
Yes, I know it's wild, but it works!

How can I detect when the user gets a View and do something after getting this position on React Native?

I have a ScrollView with some Views inside it, but I want to start an animation when the user gets to specific View and after it starts my animation.
Example:
<ScrollView style={{ width: DeviceWidth, height: DeviceWidth * 0.5 }}>
{/* When user position scroll is here,
is where I want to start the animation,
not since the page is loaded */}
<View style={{
width: DeviceWidth * 0.4,
height: DeviceWidth * 0.4,
resizeMode: "contain",
}}>
<ProgressBarAnimated
width={barWidth}
value={65}
backgroundColor="#F68D29"
height={40}
barAnimationDuration={6000}
/>
</View>
</ScrollView>
Instead of using a ScrollView you can instead use a FlatList, this gives you a lot more support for the type of indexing you're trying to do.
To detect when a user reaches a specific point you can use onViewableItemsChanged and the define which viewable items need to be on screen in order to trigger your animation.
FlatLists also support a number of build in animations like scrollToEnd or ScrollToIndex which may be helpful.

width: '100%' vs Dimension.get('window').width in react native

I'm new to react native and css styling as a whole so sorry if the question is very basic. I want a view to take 100% of the available screen width and when i use the code below my view seems to go outside the screen boundry, though when I use Dimension.get('window').width it work just fine. can someone explain how they differ from each other. any help would be really appreciated. thanks
return(
<TouchableOpacity style = {styles.food_wrapper}
onPress = {()=> this.userAction()}
>
<Text style = {styles.foodname}>
{this.name}
</Text>
<Text style = {styles.foodprice}>
Rs: {this.price}
</Text>
</TouchableOpacity>
);
food_wrapper:{
flex: 1,
flexDirection :'row',
justifyContent:'space-between',
alignItems:'flex-start',
width: '100%',//Dimensions.get('window').width,
minHeight: 50,
marginVertical: '1%',
padding: '2%',
backgroundColor: 'rgb(155,200,200)'
},
You need to understand what is the basic difference from 100% and the width you get using dimension.get('window')
100% means you want to get the container 100% width which mean if your parent container is 50px then 100% will return 50px.
the width from dimension give you a static width of your device width
so be careful to choose what to use to your component
if you want to follow the parent container then it is easier to use 100% then width from dimension but for responsive reasons without any parent container or it is the parent itself then width from dimension will work better
You need to add a wrapper view with flexDirection: 'row', then style the child view (or Touchable or whatever) with flex: 1
<View style={{ flexDirection: 'row' }}>
<View style={{ flex: 1, height: 100, backgroundColor: 'grey' }} />
</View>
Or you could use alignSelf: 'stretch' inside a few with flexDirection: 'column' (which is the default for all views)
Hang in there. Learning flexbox takes some practice. Your first thought when you get stuck should be "do I need to add a wrapper view?"

React Native: Perfectly align Text in circle

I have a circle button (made with borderRadius) in React Native. The text in the component should be centered both vertically and horizonatlly.
Horyzontally it's fine, but the vertical alignment seems to fail whatever I do. Even if it looks good on large cicles with small fontSize, the small circles proof it wrong!
<View style = {{
alignItems:'center',
justifyContent:'center',
backgroundColor:'yellow',
borderColor: this.props.color,
width:size, height:size,
borderRadius:size,
borderWidth:borderWidth,
}}>
<Text style = {{
textAlign: 'center',
backgroundColor:'none',
fontSize:fontSize,
lineHeight:fontSize,
}}>
{this.props.title}
</Text>
</View>
Although already answered elsewhere, I'm unable to center text (in this case) in a circle properly.
As one can see on the image with the green background of the <Text>-Component, the text is just not centered perfectly. Even though the itself is perfecttly aligned...
Here is a snack for Expo with the whole code reduced to the necessary and with different example sizes: https://repl.it/#PaulHuchner/Centered-Text-in-Circles
I have tried the previous answer with only Text and calculating line-height. which looks like a little overkill and didn't work for me. So here's my answer.
I am using View as the container with justifyContent:center
<View style={{
width: 40,
height: 40,
borderRadius: 20,
borderWidth: 1,
borderColor: 'black',
borderStyle: 'solid',
justifyContent: 'center'}}>
<Text style={{fontSize: 20,textAlign: 'center'}}>20</Text></View>
You're trying to set the same fontSize and lineHeight as the circle's diameter, which has borderWidth of 10 included to it.
Due to the borderWidth, the text is being cut and overlayed over the circle. The lineHeight assigned to the cut Text is more than required, hence it is displayed misaligned.
Therefore you need to reduce the fontSize and the lineHeight based on the borderRadius of the circle, to function properly for all dimensions.
<Text style = {{
textAlign: 'center',
backgroundColor:'green',
fontSize:fontSize - 2 * borderWidth, //... One for top and one for bottom alignment
lineHeight:fontSize - (Platform.OS === 'ios' ? 2 * borderWidth : borderWidth), //... One for top and one for bottom alignment
}}>
Here's a snack link
The solution that worked the best for me was instead of using a Text Element, instead, use a plus Icon. The difference is that the viewBox of "+" as a character isn't centered.
If that is confusing look at these three letters
A+a
Notice that "A" is taller than "+" and also "a". So instead, use a PLUS icon instead and it will be perfectly centered such as 24x24 px. This drove me mad!

Shaped views in react-native

How do I get the the rounded view like that? I've been messing around with borderRadius, but it's not getting how I wanted...
In short, I put a <View> around my <Image>, made that one bigger than the screen and started to change borderBottomRadius and set it to overflow:hidden
It looks very clumsy now, not beautifully rounded
<View style={Styles.border}>
<Image></Image>
</View>
Style:
border:{
flex:1,
width: width + 300,
left:-150,
top:0,
borderBottomLeftRadius:width -100,
borderBottomRightRadius:width - 100,
overflow:'hidden'
}