Category: React

Sometimes, we want to bind onPress with an argument in React Native.

In this article, we’ll look at how to bind onPress with an argument in React Native.

How to bind onPress with an argument in React Native?

To bind onPress with an argument in React Native, we can create a function that returns the onPress handler function.

For instance, we write:

import * as React from 'react';
import { Button, View } from 'react-native';
import Constants from 'expo-constants';
import { Card } from 'react-native-paper';

export default function App() {
  const onPress = (arg) => () => {
    console.log(arg);
  };

  return (
    <View>
      <Button title="button" onPress={onPress('hello')} />
    </View>
  );
}

to add a Button with the onPress prop set to the function that we get after we call onPress with 'hello'.

We define onPress to return a function that logs the arg that we passed into the outer function.

Therefore, when we press the button, we see 'hello' logged.

Conclusion

To bind onPress with an argument in React Native, we can create a function that returns the onPress handler function.

Sometimes, we want to add styling with conditional with React Native.

In this article, we’ll look at how to add styling with conditional with React Native.

How to add styling with conditional with React Native?

To add styling with conditional with React Native, we can use a function.

For instance, we write:

import * as React from 'react';
import { TextInput, View } from 'react-native';
import Constants from 'expo-constants';
import { Card } from 'react-native-paper';

export default function App() {
  const [val, setVal] = React.useState();
  const getStyles = () => {
    return {
      border: !val ? '1px solid red' : 'none',
    };
  };

  return (
    <View>
      <TextInput
        value={val}
        onChangeText={setVal}
        style={getStyles()}
        placeholder="name"
      />
    </View>
  );
}

to define the getStyles function that returns an object with the border style according to the value of val.

We use the object getStyles return as the value of style.

And we call setVal when we type into the text input.

Therefore, when the input is empty, we see a red border and no border otherwise.

Conclusion

To add styling with conditional with React Native, we can use a function.

Sometimes, we want to have content break to next line with flex when content reaches edge with Flex React Native.

In this article, we’ll look at how to have content break to next line with flex when content reaches edge with Flex React Native.

How to have content break to next line with flex when content reaches edge with Flex React Native?

To have content break to next line with flex when content reaches edge with Flex React Native, we can set flexWrap to 'wrap'.

For instance, we write:

import * as React from 'react';
import { View, Text } from 'react-native';
import Constants from 'expo-constants';
import AssetExample from './components/AssetExample';
import { Card } from 'react-native-paper';

export default function App() {
  return (
    <View
      style={{
        display: 'flex',
        flexWrap: 'wrap',
        flexDirection: 'row',
      }}>
      {Array(100)
        .fill()
        .map((_, i) => {
          return (
            <Text key={i} style={{ width: 50 }}>
              hello
            </Text>
          );
        })}
    </View>
  );
}

to set flexDirection to 'row' to set the flexbox direction to horizontal.

Then we set flexWrap to 'wrap' to make the child items wrap when it reaches the right edge of the screen.

And finally we add some Text components with width of 50 pixels as children of the View.

As a result, we see the ‘hello’ text displayed in rows.

Conclusion

To have content break to next line with flex when content reaches edge with Flex React Native, we can set flexWrap to 'wrap'.

Sometimes, we want to create a text border in React Native.

In this article, we’ll look at how to create a text border in React Native.

How to create a text border in React Native?

To create a text border in React Native, we can add a few styles.

For instance, we write:

import * as React from 'react';
import { View, Text } from 'react-native';
import Constants from 'expo-constants';
import AssetExample from './components/AssetExample';
import { Card } from 'react-native-paper';

export default function App() {
  return (
    <View style={{ flex: 1, padding: 30 }}>
      <Text
        style={{
          borderWidth: 1,
          borderColor: 'thistle',
          borderRadius: 50,
        }}>
        hello
      </Text>
    </View>
  );
}

to add the borderWidth to 1 pixel.

borderColor sets the border color.

borderRadius sets the border corner radius.

Conclusion

To create a text border in React Native, we can add a few styles.

Sometimes, we want to unfocus a TextInput in React Native.

In this article, we’ll look at how to unfocus a TextInput in React Native.

How to unfocus a TextInput in React Native?

To unfocus a TextInput in React Native, we can use the Keyboard.dismiss method.

For instance, we write:

import * as React from 'react';
import { View, Keyboard, TextInput } from 'react-native';
import Constants from 'expo-constants';
import AssetExample from './components/AssetExample';
import { Card } from 'react-native-paper';

export default function App() {
  return (
    <View style={{ flex: 1, padding: 30 }}>
      <TextInput onSubmitEditing={Keyboard.dismiss} placeholder="Name" />
    </View>
  );
}

to set the onSubmitEditing prop to Keyboard.dismiss.

As a result, when we press enter when we’re focus on the text input, the focus will move away from the text input.

Conclusion

To unfocus a TextInput in React Native, we can use the Keyboard.dismiss method.