Question

我正在android应用程序中进行Web视图，并希望实现滑动以刷新手势。但由于一个错误而无法通过。 swipe.setOnRefreshListener（SwipeRefreshLayout.OnRefreshListener（）） 应该向该函数传递什么参数？

这是我的mainactivity.kt文件


var mWebView : WebView? = null

abstract class MainActivity : AppCompatActivity() {


  lateinit var swipe:SwipeRefreshLayout


  override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
     setContentView(R.layout.activity_main)

     swipe = findViewById(R.id.swipe) as SwipeRefreshLayout
     **swipe.setOnRefreshListener(SwipeRefreshLayout.OnRefreshListener())**
     run {
         val onRefresh:Unit
         run({ Loadweb() })
 }

     }




  fun Loadweb() {
      mWebView = findViewById<View>(R.id.webView) as WebView
      mWebView!!.webViewClient = object : WebViewClient () {
          override fun shouldOverrideUrlLoading(view: WebView?, url: String?): Boolean {
              view?.loadUrl(url)
              return true
          }
      }
      val webSettings = mWebView!!.getSettings()
      webSettings.setJavaScriptEnabled(true)
      webSettings.setUseWideViewPort(true)

      mWebView!!.loadUrl("http://allnumber.info/")
  }



  override fun onBackPressed() {
      if (mWebView!!.canGoBack()){
          mWebView!!.goBack()
      }
      else {
      super.onBackPressed()
  }
}}

这是错误消息

没有传递参数'function'的值

Answer 1

尝试此代码

        private lateinit var mHandler: Handler
        private lateinit var mRunnable:Runnable     
       override fun onCreate(savedInstanceState: Bundle?) {
                 super.onCreate(savedInstanceState)
                 setContentView(R.layout.activity_main)

            // Initialize the handler instance
            mHandler = Handler()

                 swipe = findViewById(R.id.swipe) as SwipeRefreshLayout
                 swipe.setOnRefreshListener{

        mRunnable = Runnable {
                         Loadweb()
                        swipe_refresh_layout.isRefreshing = false
                    }

                    // Execute the task after specified time
                    mHandler.postDelayed(
                            mRunnable,
                            (randomInRange(1,5)*1000).toLong() // Delay 1 to 5 seconds
                    )
                }
              }


          }

Answer 2

我认为你应该通过 (object:SwipeRefreshLayout.OnRefreshListener(){ //override methods })

没有为参数“功能”传递任何值

2 个答案: