Reply To Address

app/src/main/java/com/adityapk/zcash/zqwandroid/DataModel.kt

@@ -153,7 +153,10 @@ object DataModel {
         }
     }
 
-    fun isValidAddress(a: String) : Boolean {
+    fun isValidAddress(a: String?) : Boolean {
+        if (a == null)
+            return false
+
         return if (isTestnet()) {
             Regex("^ztestsapling[a-z0-9]{76}", RegexOption.IGNORE_CASE).matches(a) ||
                     Regex("^tm[a-z0-9]{33}$", RegexOption.IGNORE_CASE).matches(a)
@@ -161,7 +164,10 @@ object DataModel {
             Regex("^z[a-z0-9]{77}$", RegexOption.IGNORE_CASE).matches(a) ||
                     Regex("^t[a-z0-9]{34}$", RegexOption.IGNORE_CASE).matches(a)
         }
+    }
 
+    fun isSaplingAddress(a: String?) : Boolean {
+        return a?.startsWith("zs") ?: false || a?.startsWith("ztestsapling") ?: false
     }
 
     private fun decrypt(nonceHex: String, encHex: String) : String {

app/src/main/java/com/adityapk/zcash/zqwandroid/SendActivity.kt

@@ -37,6 +37,12 @@ class SendActivity : AppCompatActivity() {
         txtValidAddress.text = ""
         txtSendCurrencySymbol.text = ""
 
+        if (intent.getStringExtra("address") != null)
+            sendAddress.setText(intent.getStringExtra("address"), TextView.BufferType.EDITABLE)
+
+        if (intent.getDoubleExtra("amount", -1.0) > 0)
+            setAmountUSD(intent.getDoubleExtra("amount", 0.0))
+
         imageButton.setOnClickListener { view ->
             val intent = Intent(this, QrReaderActivity::class.java)
             intent.putExtra("REQUEST_CODE", QrReaderActivity.REQUEST_ADDRESS)
@@ -91,8 +97,8 @@ class SendActivity : AppCompatActivity() {
             }
         })
 
-        txtSendMemo.setImeOptions(EditorInfo.IME_ACTION_DONE);
-        txtSendMemo.setRawInputType(InputType.TYPE_CLASS_TEXT);
+        txtSendMemo.imeOptions = EditorInfo.IME_ACTION_DONE
+        txtSendMemo.setRawInputType(InputType.TYPE_CLASS_TEXT)
 
         txtSendMemo.addTextChangedListener(object : TextWatcher {
             override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
@@ -194,6 +200,28 @@ class SendActivity : AppCompatActivity() {
 
     private fun Double.format(digits: Int): String? = java.lang.String.format("%.${digits}f", this)
 
+    private fun setAmountUSD(amt: Double) {
+        amountUSD.setText(amt.format(2))
+        setAmount(amt / (DataModel.mainResponseData?.zecprice ?: 0.0))
+    }
+
+    private fun setAmount(amt: Double?) {
+        val zprice = DataModel.mainResponseData?.zecprice
+
+        if (amt == null) {
+            txtSendCurrencySymbol.text = "" // Let the placeholder show the "$" sign
+        } else {
+            txtSendCurrencySymbol.text = "$"
+        }
+
+        if (amt == null || zprice == null)
+            amountZEC.text = "${DataModel.mainResponseData?.tokenName} 0.0"
+        else
+            amountZEC.text =
+                "${DataModel.mainResponseData?.tokenName} " + DecimalFormat("#.########").format(amt)
+
+    }
+
     override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
         when (requestCode) {
             QrReaderActivity.REQUEST_ADDRESS -> {
@@ -204,9 +232,7 @@ class SendActivity : AppCompatActivity() {
                         val amt = data.data?.getQueryParameter("amt") ?:
                                     data.data?.getQueryParameter("amount")
                         if (amt != null) {
-                            val amtUsd = amt.toDouble() * (DataModel.mainResponseData?.zecprice ?: 0.0)
-                            amountUSD.setText(amtUsd.format(2))
-                            amountZEC.text = "${DataModel.mainResponseData?.tokenName} $amt"
+                            setAmountUSD(amt.toDouble())
                         }
 
                         val memo = data.data?.getQueryParameter("memo")

app/src/main/java/com/adityapk/zcash/zqwandroid/TxDetailsActivity.kt

@@ -14,6 +14,12 @@ import java.util.*
 import android.content.Intent
 import android.net.Uri
 import android.support.constraint.ConstraintLayout
+import android.view.Menu
+import android.view.MenuItem
+import android.view.View
+import android.R.attr.right
+
+
 
 
 class TxDetailsActivity : AppCompatActivity() {
@@ -43,6 +49,13 @@ class TxDetailsActivity : AppCompatActivity() {
             txtType.text = tx?.type?.capitalize() + if (tx?.confirmations == 0L) " (Unconfirmed Tx)" else ""
             txtDateTime.text = DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.MEDIUM)
                 .format(Date((tx?.datetime ?: 0) * 1000))
+
+            // Check if there is a reply-to address
+            if (getReplyToAddress(tx?.memo) != null) {
+                btnExternal.text = "Reply"
+            } else {
+                btnExternal.visibility = View.GONE
+            }
         }
 
         txtAddress.text = if (tx?.addr.isNullOrBlank()) "(Shielded Address)" else tx?.addr
@@ -64,21 +77,56 @@ class TxDetailsActivity : AppCompatActivity() {
             if (tx?.type == "confirm") {
                 val data = Intent()
                 data.data = Uri.parse(Klaxon().toJsonString(tx))
-                setResult(Activity.RESULT_OK, data);
+                setResult(Activity.RESULT_OK, data)
 
                 finish()
             } else {
-                val uri = if (DataModel.isTestnet()) {
-                    "https://explorer.testnet.z.cash/tx/"
-                } else {
-                    "https://explorer.zcha.in/transactions/"
-                } + tx?.txid
-                val browserIntent = Intent(
-                    Intent.ACTION_VIEW,
-                    Uri.parse(uri)
-                )
-                startActivity(browserIntent)
+                val intent = Intent(this, SendActivity::class.java)
+                intent.putExtra("address", getReplyToAddress(tx?.memo))
+                intent.putExtra("amount", 0.01)
+                startActivity(intent)
+            }
+        }
+    }
+
+    private fun getReplyToAddress(memo: String?): String? {
+        if (memo == null)
+            return null
+
+        val lastPost = memo.trim().lastIndexOfAny("\r\n".toCharArray())
+        val lastWord = memo.substring(lastPost + 1)
+        return if (DataModel.isValidAddress(lastWord) && DataModel.isSaplingAddress(lastWord))
+            lastWord
+        else
+            null
+    }
+
+    private fun viewOnExplorer(txid: String?) {
+        val uri = if (DataModel.isTestnet()) {
+            "https://explorer.testnet.z.cash/tx/"
+        } else {
+            "https://explorer.zcha.in/transactions/"
+        } + txid
+        val browserIntent = Intent(
+            Intent.ACTION_VIEW,
+            Uri.parse(uri)
+        )
+        startActivity(browserIntent)
+    }
+
+    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
+        menuInflater.inflate(R.menu.menu_txdetails, menu)
+        return true
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem?): Boolean {
+        return when (item?.itemId) {
+            R.id.action_view -> {
+                viewOnExplorer(tx?.txid)
+
+                return true
             }
+            else -> super.onOptionsItemSelected(item)
         }
     }
 

app/src/main/res/menu/menu_txdetails.xml

@@ -0,0 +1,10 @@
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+      xmlns:app="http://schemas.android.com/apk/res-auto"
+      xmlns:tools="http://schemas.android.com/tools"
+      xmlns:compat="http://schemas.android.com/apk/res-auto"
+      tools:context="com.adityapk.zcash.zqwandroid.TxDetailsActivity">
+    <item android:id="@+id/action_view"
+          android:title="View"
+          android:orderInCategory="100"
+          app:showAsAction="ifRoom" android:icon="@android:drawable/ic_menu_view"/>
+</menu>

build.gradle

@@ -7,7 +7,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.3.1'
+        classpath 'com.android.tools.build:gradle:3.3.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
 
         // NOTE: Do not place your application dependencies here; they belong