import {Dimensions, Platform, PixelRatio} from 'react-native'
let { width, height } = Dimensions.get('window');
if( width > height ){
let temp = width ;
width = height ;
height = temp;
}
/**
* Converts provided width percentage to independent pixel (dp).
* @param {string} widthPercent The percentage of screen's width that UI element should cover
* along with the percentage symbol (%).
* @return {number} The calculated dp depending on current device's screen width.
*/
const widthPercentageToDP = widthPercent => {
// Parse string percentage input and convert it to number.
const elemWidth = typeof widthPercent === "number" ? widthPercent : parseFloat(widthPercent);
// Use PixelRatio.roundToNearestPixel method in order to round the layout
// size (dp) to the nearest one that correspons to an integer number of pixels.
return PixelRatio.roundToNearestPixel(width * elemWidth / 100);
};
/**
* Converts provided height percentage to independent pixel (dp).
* @param {string} heightPercent The percentage of screen's height that UI element should cover
* along with the percentage symbol (%).
* @return {number} The calculated dp depending on current device's screen height.
*/
const heightPercentageToDP = heightPercent => {
// Parse string percentage input and convert it to number.
const elemHeight = typeof heightPercent === "number" ? heightPercent : parseFloat(heightPercent);
// Use PixelRatio.roundToNearestPixel method in order to round the layout
// size (dp) to the nearest one that correspons to an integer number of pixels.
return PixelRatio.roundToNearestPixel(height * elemHeight / 100);
};
/**
* Event listener function that detects orientation change (every time it occurs) and triggers
* screen rerendering. It does that, by changing the state of the screen where the function is
* called. State changing occurs for a new state variable with the name 'orientation' that will
* always hold the current value of the orientation after the 1st orientation change.
* Invoke it inside the screen's constructor or in componentDidMount lifecycle method.
* @param {object} that Screen's class component this variable. The function needs it to
* invoke setState method and trigger screen rerender (this.setState()).
*/
const listenOrientationChange = that => {
Dimensions.addEventListener('change', newDimensions => {
// Retrieve and save new dimensions
width = newDimensions.window.width;
height = newDimensions.window.height;
// Trigger screen's rerender with a state update of the orientation variable
that.setState({
orientation: width < height ? 'portrait' : 'landscape'
});
});
};
/**
* Wrapper function that removes orientation change listener and should be invoked in
* componentWillUnmount lifecycle method of every class component (UI screen) that
* listenOrientationChange function has been invoked. This should be done in order to
* avoid adding new listeners every time the same component is re-mounted.
*/
const removeOrientationListener = () => {
Dimensions.removeEventListener('change', () => {});
};
// Used via Metrics.baseMargin
const metrics = {
marginHorizontal: 10,
marginVertical: 10,
section: 25,
baseMargin: 10,
doubleBaseMargin: 20,
smallMargin: 5,
doubleSection: 50,
horizontalLineHeight: 1,
screenWidth: width < height ? width : height,
screenHeight: width < height ? height : width,
navBarHeight: (Platform.OS === 'ios') ? 64 : 54,
buttonRadius: 4,
icons: {
tiny: 15,
small: 20,
medium: 30,
large: 45,
xl: 50
},
images: {
small: 20,
medium: 40,
large: 60,
logo: 200
},
widthPercentageToDP,
heightPercentageToDP,
listenOrientationChange,
removeOrientationListener
}
export default metrics