【发布时间】：2021-07-15 13:43:02
【问题描述】：
我有一个 cartActivity，当我单击继续按钮时，它会转到 PaymentActivity。现在，如果我从 paymentActivity 中单击返回按钮，我想返回 CartActivity。
购物车活动
class CartActivity : AppCompatActivity() {
lateinit var toolbar: androidx.appcompat.widget.Toolbar
lateinit var txtOrderingFrom: TextView
lateinit var btnPlaceOrder: Button
lateinit var recyclerView: RecyclerView
lateinit var layoutManager: RecyclerView.LayoutManager
lateinit var menuAdapter: CartAdapter
lateinit var restaurantId: String
lateinit var restaurantName: String
lateinit var selectedItemsId: ArrayList<String>
lateinit var linearLayout: LinearLayout
lateinit var cartProgressLayout: RelativeLayout
var totalAmount = 0
var cartListItems = arrayListOf<CartItems>()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_cart)
btnPlaceOrder = findViewById(R.id.btnPlaceOrder)
txtOrderingFrom = findViewById(R.id.txtOrderingFrom)
linearLayout = findViewById(R.id.linearLayout)
toolbar = findViewById(R.id.toolBar)
cartProgressLayout = findViewById(R.id.cartProgressLayout)
restaurantId = intent.getStringExtra("restaurantId").toString()
restaurantName = intent.getStringExtra("restaurantName").toString()
selectedItemsId = intent.getStringArrayListExtra("selectedItemsId") as ArrayList<String>
txtOrderingFrom.text = restaurantName
setToolBar()
fetchData()
btnPlaceOrder.setOnClickListener {
val sharedPreferences = this.getSharedPreferences(
getString(R.string.shared_preferences),
Context.MODE_PRIVATE
)
if (ConnectionManager().checkConnectivity(this)) {
cartProgressLayout.visibility = View.VISIBLE
try {
val foodArray = JSONArray()
for (foodItem in selectedItemsId) {
val singleItemObject = JSONObject()
singleItemObject.put("food_item_id", foodItem)
foodArray.put(singleItemObject)
}
val sendOrder = JSONObject()
sendOrder.put("user_id", sharedPreferences.getString("user_id", "0"))
sendOrder.put("restaurant_id", restaurantId)
sendOrder.put("total_cost", totalAmount)
sendOrder.put("food", foodArray)
val queue = Volley.newRequestQueue(this)
val url = "http://13.235.250.119/v2/place_order/fetch_result"
val jsonObjectRequest = object : JsonObjectRequest(
Method.POST,
url,
sendOrder,
Response.Listener {
val response = it.getJSONObject("data")
val success = response.getBoolean("success")
val LAUNCH_SECOND_ACTIVITY = 1
if (success) {
val intent = Intent(this, PaymentActivity::class.java)
intent.putExtra("total_amount",totalAmount)
startActivityForResult(intent,LAUNCH_SECOND_ACTIVITY)
finishAffinity()
} else {
val responseMessageServer =
response.getString("errorMessage")
Toast.makeText(
this,
responseMessageServer.toString(),
Toast.LENGTH_SHORT
).show()
}
cartProgressLayout.visibility = View.INVISIBLE
},
Response.ErrorListener {
Toast.makeText(
this,
"Some Error occurred!!!",
Toast.LENGTH_SHORT
).show()
}) {
override fun getHeaders(): MutableMap<String, String> {
val headers = HashMap<String, String>()
headers["Content-type"] = "application/json"
headers["token"] = "9bf534118365f1"
return headers
}
}
queue.add(jsonObjectRequest)
} catch (e: JSONException) {
Toast.makeText(
this,
"Some unexpected error occurred!!",
Toast.LENGTH_SHORT
).show()
}
} else {
val alterDialog = androidx.appcompat.app.AlertDialog.Builder(this)
alterDialog.setTitle("No Internet")
alterDialog.setMessage("Check Internet Connection!")
alterDialog.setPositiveButton("Open Settings") { _, _ ->
val settingsIntent = Intent(Settings.ACTION_SETTINGS)
startActivity(settingsIntent)
}
alterDialog.setNegativeButton("Exit") { _, _ ->
finishAffinity()
}
alterDialog.setCancelable(false)
alterDialog.create()
alterDialog.show()
}
}
layoutManager = LinearLayoutManager(this)
recyclerView = findViewById(R.id.recyclerViewCart)
}
fun fetchData() {
if (ConnectionManager().checkConnectivity(this)) {
cartProgressLayout.visibility = View.VISIBLE
try {
val queue = Volley.newRequestQueue(this)
val url = "http://13.235.250.119/v2/restaurants/fetch_result/$restaurantId"
val jsonObjectRequest = @SuppressLint("SetTextI18n")
object : JsonObjectRequest(
Method.GET,
url,
null,
Response.Listener {
val response = it.getJSONObject("data")
val success = response.getBoolean("success")
if (success) {
val data = response.getJSONArray("data")
cartListItems.clear()
totalAmount = 0
for (i in 0 until data.length()) {
val cartItem = data.getJSONObject(i)
if (selectedItemsId.contains(cartItem.getString("id"))) {
val menuObject = CartItems(
cartItem.getString("id"),
cartItem.getString("name"),
cartItem.getString("cost_for_one"),
cartItem.getString("restaurant_id")
)
totalAmount += cartItem.getString("cost_for_one").toString()
.toInt()
cartListItems.add(menuObject)
}
menuAdapter = CartAdapter(this, cartListItems)
recyclerView.adapter = menuAdapter
recyclerView.layoutManager = layoutManager
}
btnPlaceOrder.text = "Place Order(Total: Rs. $totalAmount)"
}
cartProgressLayout.visibility = View.INVISIBLE
},
Response.ErrorListener {
Toast.makeText(
this,
"Some Error occurred!!!",
Toast.LENGTH_SHORT
).show()
cartProgressLayout.visibility = View.INVISIBLE
}) {
override fun getHeaders(): MutableMap<String, String> {
val headers = HashMap<String, String>()
headers["Content-type"] = "application/json"
headers["token"] = "26c5144c5b9c13"
return headers
}
}
queue.add(jsonObjectRequest)
} catch (e: JSONException) {
Toast.makeText(
this,
"Some Unexpected error occurred!!!",
Toast.LENGTH_SHORT
).show()
}
} else {
val alterDialog = androidx.appcompat.app.AlertDialog.Builder(this)
alterDialog.setTitle("No Internet")
alterDialog.setMessage("Check Internet Connection!")
alterDialog.setPositiveButton("Open Settings") { _, _ ->
val settingsIntent = Intent(Settings.ACTION_SETTINGS)
startActivity(settingsIntent)
}
alterDialog.setNegativeButton("Exit") { _, _ ->
finishAffinity()
}
alterDialog.setCancelable(false)
alterDialog.create()
alterDialog.show()
}
}
fun setToolBar() {
setSupportActionBar(toolbar)
supportActionBar?.title = "My Cart"
supportActionBar?.setHomeButtonEnabled(true)
supportActionBar?.setDisplayHomeAsUpEnabled(true)
supportActionBar?.setHomeAsUpIndicator(R.drawable.ic_back_arrow)
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
when (item.itemId) {
android.R.id.home -> {
super.onBackPressed()
}
}
return super.onOptionsItemSelected(item)
}
}
支付活动
class PaymentActivity : AppCompatActivity() {
var amountEt: TextView? = null
var nameEt: TextView? = null
var upiIdEt: TextView? = null
var send: Button? = null
val UPI_PAYMENT = 0
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_payment)
initializeViews()
send?.setOnClickListener {
payUsingUpi("1", "sruthikrithika0@okhdfcbank", "Sruthi")
}
}
fun initializeViews() {
send = findViewById(R.id.send)
amountEt = findViewById(R.id.amount_et)
nameEt = findViewById(R.id.upi_name)
upiIdEt = findViewById(R.id.upi_id)
}
fun payUsingUpi(amount: String?, upiId: String?, name: String?) {
val uri: Uri = Uri.parse("upi://pay").buildUpon()
.appendQueryParameter("pa", upiId)
.appendQueryParameter("pn", name)
.appendQueryParameter("am", amount)
.appendQueryParameter("cu", "INR")
.build()
val upiPayIntent = Intent(Intent.ACTION_VIEW)
upiPayIntent.data = uri
// will always show a dialog to user to choose an app
val chooser = Intent.createChooser(upiPayIntent, "Pay with")
// check if intent resolves
if (null != chooser.resolveActivity(packageManager)) {
startActivityForResult(chooser, UPI_PAYMENT)
} else {
Toast.makeText(
this@PaymentActivity,
"No UPI app found, please install one to continue",
Toast.LENGTH_SHORT
).show()
}
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
when (requestCode) {
UPI_PAYMENT -> if (RESULT_OK == resultCode || resultCode == 11) {
if (data != null) {
val trxt = data.getStringExtra("response")
Log.d("UPI", "onActivityResult: $trxt")
val dataList: ArrayList<String?> = ArrayList()
dataList.add(trxt)
upiPaymentDataOperation(dataList)
} else {
Log.d("UPI", "onActivityResult: " + "Return data is null")
val dataList: ArrayList<String?> = ArrayList()
dataList.add("nothing")
upiPaymentDataOperation(dataList)
}
} else {
Log.d(
"UPI",
"onActivityResult: " + "Return data is null"
) //when user simply back without payment
val dataList: ArrayList<String?> = ArrayList()
dataList.add("nothing")
upiPaymentDataOperation(dataList)
}
}
}
private fun upiPaymentDataOperation(data: ArrayList<String?>) {
if (isConnectionAvailable(this@PaymentActivity)) {
var str = data[0]
Log.d("UPIPAY", "upiPaymentDataOperation: $str")
var paymentCancel = ""
if (str == null) str = "discard"
var status = ""
var approvalRefNo = ""
val response = str.split("&").toTypedArray()
for (i in response.indices) {
val equalStr = response[i].split("=").toTypedArray()
if (equalStr.size >= 2) {
if (equalStr[0].toLowerCase() == "Status".toLowerCase()) {
status = equalStr[1].toLowerCase()
} else if (equalStr[0].toLowerCase() == "ApprovalRefNo".toLowerCase() || equalStr[0].toLowerCase() == "txnRef".toLowerCase()) {
approvalRefNo = equalStr[1]
}
} else {
paymentCancel = "Payment cancelled by user."
}
}
if (status == "success") {
//Code to handle successful transaction here.
Toast.makeText(this@PaymentActivity, "Transaction successful.", Toast.LENGTH_SHORT)
.show()
Log.d("UPI", "responseStr: $approvalRefNo")
} else if ("Payment cancelled by user." == paymentCancel) {
Toast.makeText(this@PaymentActivity, "Payment cancelled by user.", Toast.LENGTH_SHORT)
.show()
} else {
Toast.makeText(
this@PaymentActivity,
"Transaction failed.Please try again",
Toast.LENGTH_SHORT
).show()
}
} else {
Toast.makeText(
this@PaymentActivity,
"Internet connection is not available. Please check and try again",
Toast.LENGTH_SHORT
).show()
}
}
companion object {
fun isConnectionAvailable(context: Context): Boolean {
val connectivityManager =
context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
if (connectivityManager != null) {
val netInfo = connectivityManager.activeNetworkInfo
if (netInfo != null && netInfo.isConnected
&& netInfo.isConnectedOrConnecting
&& netInfo.isAvailable
) {
return true
}
}
return false
}
}
}
现在，当我从 PaymentActivity 单击返回按钮时，应用程序崩溃，因为 cartActivity 中的相同状态不存在。如何解决这个问题？？
清单文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.foodly">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:allowBackup="true"
android:hardwareAccelerated="true"
android:icon="@drawable/logo"
android:label="@string/app_name"
android:networkSecurityConfig="@xml/network_security_config"
android:resizeableActivity="false"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.Foodly">
<activity android:name=".activity.OrderPlacedActivity"></activity>
<activity android:name=".activity.CartActivity" />
<activity android:name=".activity.OrderHistoryActivity" />
<activity
android:name=".activity.RestaurantMenuActivity" />
<activity
android:name=".activity.RegisterActivity" />
<activity
android:name=".activity.LoginActivity" />
<activity
android:name=".activity.PaymentActivity"/>
<activity
android:name=".activity.SplashActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".activity.MainActivity" />
<meta-data
android:name="preloaded_fonts"
android:resource="@array/preloaded_fonts" />
</application>
</manifest>
【问题讨论】：
-
如果您显示堆栈跟踪并指出它对应的行会有所帮助，这样我们就不必仔细阅读所有代码来发现错误...
-
如果你看到 PaymentActivity，我已经实现了 onBackPressed。但是如果我按下它就不会返回，因为购物车项目没有保存
-
你要让我乞求堆栈跟踪吗？ ;)
-
您已经花时间回复多个答案 - 如果您花时间发布崩溃的堆栈跟踪，这可能已经解决了。
-
我其实不知道该怎么做。我是安卓新手。对不起@dominicoder
标签： android xml android-studio kotlin