Soma: Created page with "==Code== package carleton.comp2601.webviewcompose import android.os.Bundle import android.util.Log import android.view.ViewGroup import android.webkit.WebResourceRequest import android.webkit.WebView import android.webkit.WebViewClient import androidx.activity.ComponentActivity import androidx.activity.compose.setContent import androidx.compose.foundation.layout.Row import androidx.compose.foundation.text.ClickableText import androi..."

2023-03-31T22:05:56Z

Created page with "==Code== <syntaxhighlight lang="kotlin" line> package carleton.comp2601.webviewcompose import android.os.Bundle import android.util.Log import android.view.ViewGroup import android.webkit.WebResourceRequest import android.webkit.WebView import android.webkit.WebViewClient import androidx.activity.ComponentActivity import androidx.activity.compose.setContent import androidx.compose.foundation.layout.Row import androidx.compose.foundation.text.ClickableText import androi..."

New page

==Code==

<syntaxhighlight lang="kotlin" line>
package carleton.comp2601.webviewcompose

import android.os.Bundle
import android.util.Log
import android.view.ViewGroup
import android.webkit.WebResourceRequest
import android.webkit.WebView
import android.webkit.WebViewClient
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.text.ClickableText
import androidx.compose.material.*
import androidx.compose.runtime.*
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.text.AnnotatedString
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.viewinterop.AndroidView

class MainActivity : ComponentActivity() {

override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContent {
// Calling the composable function
// to display element and its contents
MainContent()
}
}
}

// Creating a composable
// function to display Top Bar
@Composable
fun MainContent() {
var curURL by remember { mutableStateOf("https://news.ycombinator.com") }
var history = mutableListOf<String>("https://news.ycombinator.com")
var curURLIndex = 0

fun updateURL(newURL: String) {
curURLIndex += 1
history.add(curURLIndex, newURL)
val lastIndex = history.lastIndex
if (lastIndex > curURLIndex) {
for (i in curURLIndex + 1..lastIndex) {
history.removeAt(i)
}
}
curURL = newURL
Log.d("webviewCompose", "updating URL to $curURL")
}

fun prevURL() {
curURLIndex -= 1
if (curURLIndex < 0) {
curURLIndex = 0
}
curURL = history[curURLIndex]
Log.d("webviewCompose", "going to previous URL $curURL")
}

fun nextURL() {
curURLIndex += 1
if (curURLIndex > history.lastIndex) {
curURLIndex = history.lastIndex
}
curURL = history[curURLIndex]
Log.d("webviewCompose", "going to next URL $curURL")
}

Scaffold(
// topBar = { TopAppBar(title = {Text("COMP 2601")})},
topBar = {
Row {
ClickableText(
AnnotatedString(text = "Back"),
onClick = {
prevURL()
}
)
ClickableText(
AnnotatedString(text = "Forward"),
onClick = {
nextURL()
}
)
URLBar(curURL = curURL, updateURL = ::updateURL)
}
},
content = { MyContent(curURL = curURL, updateURL = ::updateURL) }
)
}

@Composable
fun URLBar(curURL: String, updateURL: (String) -> Unit) {
var newURL = ""

TextField(
value = curURL,
//onFocusChange = { updateURL(newURL) },
//onValueChange = { updatedURL: String -> newURL = updatedURL},
onValueChange = updateURL,
label = { Text("Enter URL here") }
)
}

@Composable
fun MyContent(curURL: String, updateURL: (String) -> Unit) {

class ObservableWebViewClient : WebViewClient() {

override fun shouldOverrideUrlLoading(view: WebView?, request: WebResourceRequest): Boolean {
val url = request.url

if (!request.isRedirect) {
updateURL(url.toString())
}
return false
}
}

fun logWebViewHistory(view: WebView) {
val history = view.copyBackForwardList()

val current = history.currentIndex

Log.d("webviewCompose", "Current history item: $current")

Log.d("webviewCompose", "Webview BackForwardList contents:")

for (i in 0..history.size -1) {
val item = history.getItemAtIndex(i)

if (item != null) {
val u = item.originalUrl
Log.d("webviewCompose", " $i: $u")
}
}
}

// Adding a WebView inside AndroidView
// with layout as full screen
AndroidView(factory = {
WebView(it).apply {
// layoutParams = ViewGroup.LayoutParams(
// ViewGroup.LayoutParams.MATCH_PARENT,
// ViewGroup.LayoutParams.MATCH_PARENT
// )
webViewClient = ObservableWebViewClient()
loadUrl(curURL)
}
}, update = {
Log.d("webviewCompose", "loading URL $curURL")
it.loadUrl(curURL)
//logWebViewHistory(it)
})
}

// For displaying preview in
// the Android Studio IDE emulator
@Preview(showBackground = true)
@Composable
fun DefaultPreview() {
MainContent()
}
</syntaxhighlight>

Mobile Apps 2023W Lecture 22 - Revision history