Context Extensions

ContextExtensions

Extensions for Android Context contains context releted extensions such as check network status, start an Activity, Load content from assets, compute status bar and screen height etc.

```kotlin tab="ContextExtensions.kt"

import android.Manifest import android.app.Activity import android.content.Context import android.content.Intent import android.graphics.drawable.Drawable import android.net.ConnectivityManager import android.os.Parcelable import android.util.DisplayMetrics import android.view.WindowManager import android.widget.Toast import androidx.annotation.ColorRes import androidx.annotation.DrawableRes import androidx.annotation.RequiresPermission import androidx.annotation.StringRes import androidx.core.content.ContextCompat import java.io.IOException import java.nio.charset.Charset

/* * Created by Chathura Wijesinghe on 2019-06-12. * Elegantmedia * chaturaw.emedia@gmail.com /

/* * Checks network connectivity / @RequiresPermission(Manifest.permission.ACCESS_NETWORK_STATE) fun Context.isNetworkStatusAvailable(): Boolean { val connectivityManager = this .getSystemService(Context.CONNECTIVITY_SERVICE) as? ConnectivityManager connectivityManager?.let { val netInfo = it.activeNetworkInfo netInfo?.let { if (netInfo.isConnected) return true } } return false }

/* * Execute block of code if network is available / @RequiresPermission(Manifest.permission.ACCESS_NETWORK_STATE) inline fun Context.withNetwork(available: () -> Unit,error: () -> Unit) { if (isNetworkStatusAvailable()) { available() }else{ error() } }

/* * Loads content of file from assets as String using UTF-8 charset / fun Context.loadFromAsset(jsonName: String): String? { var stream: String? = null try { val inputStream = this.assets.open(jsonName) val size = inputStream.available() val buffer = ByteArray(size) inputStream.read(buffer) inputStream.close() stream = String(buffer, Charset.forName("UTF-8")) } catch (e: IOException) { } return stream }

/* * Computes status bar height / fun Context.getStatusBarHeight(): Int { var result = 0 val resourceId = this.resources.getIdentifier("status_bar_height", "dimen", "android") if (resourceId > 0) { result = this.resources.getDimensionPixelSize(resourceId) } return result }

/* * Computes screen height / fun Context.getScreenHeight(): Int { var screenHeight = 0 val wm = this.getSystemService(Context.WINDOW_SERVICE) as? WindowManager wm?.let { val metrics = DisplayMetrics() wm.defaultDisplay.getMetrics(metrics) screenHeight = metrics.heightPixels } return screenHeight }

/* * Convert dp integer to pixel / fun Context.dpToPx(dp : Int): Float { val displayMetrics = this.resources.displayMetrics return Math.round(dp * (displayMetrics.xdpi / DisplayMetrics.DENSITY_DEFAULT)).toFloat() }

/* * Get color from resources / fun Context.getCompatColor(@ColorRes colorInt: Int) : Int = ContextCompat.getColor(this, colorInt)

/* * Get drawable from resources / fun Context.getCompatDrawable(@DrawableRes drawableRes: Int) : Drawable? = ContextCompat.getDrawable(this, drawableRes)

/* * Start Activity from context * / inline fun Context?.startActivity() = this?.startActivity(Intent(this, T::class.java))

inline fun Activity?.startActivityForResult(result : Int) = this?.startActivityForResult(Intent(this, T::class.java),result)

/* * Show Short Toast message from string resource * / fun Context?.toastShort(@StringRes textId: Int, duration: Int = Toast.LENGTH_SHORT) = this?.let { Toast.makeText(it, textId, duration).show() }

/* * Show Long Toast message from string resource * / fun Context?.toastLong(@StringRes textId: Int, duration: Int = Toast.LENGTH_LONG) = this?.let { Toast.makeText(it, textId, duration).show() }

/* * Show Long Toast message from string / fun Context?.toastLong(text: String, duration: Int = Toast.LENGTH_LONG) = this?.let { Toast.makeText(it, text, duration).show() }

/* * This function allows add Parcelable to intent which takes class name as Extra's name * / fun Intent?.putParcelable(T: Parcelable) = this?.putExtra(T::class.simpleName,T)

### Usage 

#### Network

```kotlin tab="Network Status"
    var isNetwork = mContext.isNetworkStatusAvailable()

```kotlin tab="withNetwork" Activity?.withNetwork( { // Do stuff here when the network available }, { // Network is not available handle ME :) ! } )

OR

Context?.withNetwork(
    {
     // Do stuff here when the network available
    },
    {
        // Network is not available handle ME :) !
    }
)

```