【发布时间】：2018-11-09 09:22:08
【问题描述】：
我正在尝试在我的应用程序加载数据 json url 时添加加载对话框，因为在午餐应用程序出现数据之前显示空白屏幕
这里是代码
inner class Dep : AsyncTask<String, String, String>(){
// for build connection
override fun doInBackground(vararg url: String?): String{
var text : String
val connection = URL(url[0]).openConnection() as HttpURLConnection
try {
connection.connect()
text = connection.inputStream.use { it.reader().use{reader -> reader.readText()} }
} finally{
connection.disconnect()
}
return text
}
override fun onPostExecute(result: String?) {
val progressDialog = ProgressDialog(Context,this@MainActivity)
progressDialog.setMessage("loading")
progressDialog.setCancelable(false)
progressDialog.show()
super.onPostExecute(result)
handleJson(result)
if (progressDialog != null)
progressDialog.dismiss();
}
private fun handleJson (jsonString: String?){
val jsonObj = JSONObject(jsonString)
val result = jsonObj.getJSONObject("result")
val response = result.getJSONObject("response")
val airport = response.getJSONObject("airport")
val pluginData = airport.getJSONObject("pluginData")
val schedule = pluginData.getJSONObject("schedule")
val arrivals = schedule.getJSONObject("departures")
// val data = arrivals.getJSONObject("data")
val jsonArray = JSONArray(arrivals.get("data").toString())
val list = ArrayList<FlightShdu>()
var x = 0
while (x < jsonArray.length()){
val jsonObject = jsonArray.getJSONObject(x)
list.add(FlightShdu(
jsonObject.getJSONObject("flight").getJSONObject("identification").getJSONObject("number").getString("default"),
jsonObject.getJSONObject("flight").getJSONObject("airline").getString("name"),
jsonObject.getJSONObject("flight").getJSONObject("status").getString("text"),
jsonObject.getJSONObject("flight").getJSONObject("airline").getJSONObject("code").getString("icao"),
jsonObject.getJSONObject("flight").getJSONObject("time").getJSONObject("scheduled").getString("departure")
))
x++
}
list.forEach(::println)
val adapter = ListAdapte(this@MainActivity,list)
flight_dep_list.adapter = adapter
}
// for get items from json api
override fun onProgressUpdate(vararg values: String?) {
}
}
我在onPostExecute中使用了进度对话框代码
override fun onPostExecute(result: String?) {
val progressDialog = ProgressDialog(Context,this@MainActivity)
progressDialog.setMessage("loading")
progressDialog.setCancelable(false)
progressDialog.show()
super.onPostExecute(result)
handleJson(result)
if (progressDialog != null)
progressDialog.dismiss();
}
我遇到红线错误
classifier 'Context' dose not have a companion object , and thus must be initialized here
我需要添加进度对话框 xml 吗？
【问题讨论】：
-
你应该在你的内部类下声明 ProgressDialog。然后在 onBeforeExecute() 下分离 Dialog 并显示它。将其隐藏在 onPostExecuteFunction 下（在执行后显示对话框为时已晚）
-
progressdialog 已弃用，请改用进度条
-
你能给我举个例子吗1
标签： kotlin progressdialog