Enable sharing QRCode

app/src/main/AndroidManifest.xml

@@ -32,6 +32,16 @@
                 <data android:mimeType="message/*" />
             </intent-filter>
         </activity>
+
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="org.fnives.android.qrcodetransfer.fileprovider"
+            android:grantUriPermissions="true"
+            android:exported="false">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/filepaths" />
+        </provider>
     </application>
 
 </manifest>

app/src/main/java/org/fnives/android/qrcodetransfer/Util.kt

@@ -14,11 +14,14 @@ import android.graphics.Color
 import android.icu.text.MessageFormat
 import android.net.Uri
 import android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS
+import androidx.core.content.ContextCompat
+import androidx.core.content.FileProvider
 import com.google.zxing.BinaryBitmap
 import com.google.zxing.LuminanceSource
 import com.google.zxing.RGBLuminanceSource
 import com.google.zxing.common.BitMatrix
 import com.google.zxing.common.HybridBinarizer
+import java.io.File
 import java.util.Locale
 
 
@@ -60,8 +63,8 @@ fun Int.toOrdinal(): String {
 }
 
 fun Context.copyToClipboard(text: String) {
-    val clipboard = getSystemService(CLIPBOARD_SERVICE) as ClipboardManager;
+    val clipboard = getSystemService(CLIPBOARD_SERVICE) as ClipboardManager
-    val clipData = ClipData.newPlainText("label", text);
+    val clipData = ClipData.newPlainText("label", text)
     clipboard.setPrimaryClip(clipData)
 }
 
@@ -77,3 +80,49 @@ fun Context.openLink(link: String) {
 
     }
 }
+
+private val Context.sharedDir: File
+    get() {
+        // must be the same as in filepaths.xml!
+        val cachePath = File(cacheDir, "shared")
+        cachePath.mkdirs()
+        return cachePath
+    }
+
+private val Context.sharedFile: File
+    get() {
+        // must be the same as in filepaths.xml!
+        return File(sharedDir, "qrcode.jpg")
+    }
+
+private fun Context.bitmapToSharedFile(bitmap: Bitmap): Boolean {
+    try {
+        sharedFile.createNewFile()
+        sharedFile.outputStream().use { stream ->
+            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream)
+        }
+        return true
+    } catch (e: Throwable) {
+        e.printStackTrace()
+        return false
+    }
+}
+
+private fun Context.shareQRCodeImageFile() {
+    // must be the same as in manifest.xml!
+    val contentUri = FileProvider.getUriForFile(this, "${packageName}.fileprovider", sharedFile)
+        ?: return
+
+    val shareIntent = Intent()
+    shareIntent.action = Intent.ACTION_SEND
+    shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION) // temp permission for receiving app to read this file
+    shareIntent.setDataAndType(contentUri, contentResolver.getType(contentUri))
+    shareIntent.putExtra(Intent.EXTRA_STREAM, contentUri)
+    val chooserIntent = Intent.createChooser(shareIntent, ContextCompat.getString(this, R.string.share))
+    ContextCompat.startActivity(this, chooserIntent, null)
+}
+
+fun Context.shareBitmap(bitmap: Bitmap) {
+    bitmapToSharedFile(bitmap)
+    shareQRCodeImageFile()
+}

app/src/main/java/org/fnives/android/qrcodetransfer/create/CreateQRCode.kt

@@ -2,6 +2,7 @@ package org.fnives.android.qrcodetransfer.create
 
 import android.graphics.Bitmap
 import androidx.compose.foundation.Image
+import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -34,6 +35,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.alpha
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalSoftwareKeyboardController
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.input.ImeAction
@@ -45,6 +47,7 @@ import kotlinx.coroutines.withContext
 import org.fnives.android.qrcodetransfer.R
 import org.fnives.android.qrcodetransfer.SequenceProtocol
 import org.fnives.android.qrcodetransfer.intent.LocalIntentText
+import org.fnives.android.qrcodetransfer.shareBitmap
 import org.fnives.android.qrcodetransfer.storage.LocalAppPreferences
 import org.fnives.android.qrcodetransfer.toBitmap
 
@@ -87,6 +90,7 @@ fun QRCodeCarousel(
     bitmapIndex: Int,
     setBitmapIndex: (Int) -> Unit
 ) {
+    val context = LocalContext.current
     Column(Modifier.fillMaxSize()) {
         val imageBitmap = remember(bitmaps, bitmapIndex) {
             if (bitmapIndex < bitmaps.size) {
@@ -100,7 +104,8 @@ fun QRCodeCarousel(
             Image(
                 modifier = Modifier
                     .weight(1f)
-                    .fillMaxWidth(),
+                    .fillMaxWidth()
+                    .clickable { context.shareBitmap(bitmaps[bitmapIndex]) },
                 bitmap = imageBitmap,
                 contentDescription = "",
                 contentScale = ContentScale.Fit

app/src/main/res/values/strings.xml

@@ -19,4 +19,5 @@
     <string name="open">Open</string>
     <string name="read_qr_code">Scan QR Code</string>
     <string name="create_qr_code">Create QR Code</string>
+    <string name="share">Share QR Code</string>
 </resources>

app/src/main/res/xml/filepaths.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<paths>
+    <cache-path name="qrcode" path="shared"/>
+</paths>