Question

我在Udacity上制作了Android Kotlin教程，但是我的代码无法正常工作。请查看我的代码为什么不起作用。问题是SELECT `ringtunes`.*, count(case when ringtune_history.Action = 'Download' then ringtune_history.Action end) as Org_Downloads, count(case when ringtune_history.Action = 'View' then ringtune_history.Action end) as Org_Views, count(case when ringtune_history.Action = 'Play' then ringtune_history.Action end) as Total_Plays, count(case when ringtune_history.Action = 'Like' then ringtune_history.Action end) as Total_Likes, `categories`.`Name` as `Category_Name` FROM `ringtunes` LEFT JOIN `ringtune_history` ON `ringtune_history`.`Ringtune_Id` = `ringtunes`.`Id` LEFT JOIN `categories` ON `categories`.`Id` = `ringtunes`.`Category` WHERE `ringtunes`.`Deleted` = 0 AND `ringtunes`.`Status` = 1 AND `categories`.`Deleted` = 0 AND `categories`.`Status` = 1 GROUP BY `ringtunes`.`Id` ORDER BY `ringtunes`.`Id` DESC LIMIT 20没有运行。

这是我的MainActivity.kt

binding.doneButton.setOnClickListener

我在我的activity_main.xml中添加了package hu.webfeszek.aboutme import android.content.Context import android.os.Bundle import android.util.Log import android.view.View import android.view.inputmethod.InputMethodManager import androidx.appcompat.app.AppCompatActivity import androidx.databinding.DataBindingUtil // import kotlinx.android.synthetic.main.activity_main.* import hu.webfeszek.aboutme.databinding.ActivityMainBinding class MainActivity : AppCompatActivity() { private lateinit var binding: ActivityMainBinding override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) binding = DataBindingUtil.setContentView(this, R.layout.activity_main) setContentView(R.layout.activity_main) binding.doneButton.setOnClickListener { // This code does running never Log.i("LOG_ME", binding.doneButton.text.toString()) addNickName(it) } } private fun addNickName(view:View) { } }，并在build.gradle中添加了3行：

<layout>

Answer 1

请确保每次使用数据绑定进行更改时都重新构建项目，因为您需要为所做的每次更改生成代码。如果您使用的是Android Studio，请进行项目重建。还要删除setContentView(R.layout.activity_main)，因为您正在使用数据绑定，所以不需要此行。

此外，您的xml按钮应如下所示：

     <Button
            android:text="Done"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/done_button"
            style="@style/Widget.AppCompat.Button.Colored"/>

您的Kotlin类onCreate：

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    binding = DataBindingUtil.setContentView(this, R.layout.activity_main)

    binding.doneButton.setOnClickListener {
        addNickname(view:View)
  }

数据绑定setOnClickListener未调用

1 个答案: