为什么此代码不起作用？使用Kotlin显示对话框

Question

单击浮动动作按钮时，我想创建一个对话框窗口。但是，当我单击按钮时，仅显示Toast消息。

这是我到目前为止尝试过的：

    recyclerView.layoutManager = LinearLayoutManager(this, RecyclerView.VERTICAL, false)
    val users = ArrayList<User>()

    users.add(User("John", "USA"))

    val adapter = CustomAdapter(users)

    recyclerView.adapter = adapter

    fab.setOnClickListener {
        val dialog = Dialog(this)
        Toast.makeText(this, "It's working...", Toast.LENGTH_LONG).show()
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE)
        dialog.setContentView(R.layout.dialog_add)
        dialog.setTitle("Add person")
        dialog.setCancelable(false)

        val nameText = dialog.findViewById(R.id.name) as EditText
        val addressText = dialog.findViewById(R.id.address) as EditText
        val btnAdd = dialog.findViewById(R.id.btn_ok) as Button
        val btnCancel = dialog.findViewById(R.id.btn_cancel) as Button

        btnAdd.setOnClickListener{
            users.add(User(nameText.text.toString(), addressText.text.toString()))
            adapter.notifyDataSetChanged()
            dialog.dismiss()
        }
        btnCancel.setOnClickListener {
            dialog.dismiss()
        }
    }
}

如何更改代码，以便在单击FAB时显示对话框窗口？

Answer 1

您忘记了在对话框上调用show（）。dialog.show（）

Answer 2

您需要调用dialog.show（）。只需在dialog.setCancelable（false）下的任何位置调用它即可。

Answer 3

您必须像以下那样调用show()。

//...
dialog.setTitle("Add person")
dialog.setCancelable(false)
// ...
btnAdd.setOnClickListener{
    //...
}
btnCancel.setOnClickListener {
    dialog.dismiss()
}

//show alert dialog.
dialog.show();

Answer 4

创建对话框后，我们需要调用show方法在屏幕上显示对话框

请替换或添加此代码

recyclerView.layoutManager = LinearLayoutManager(this, RecyclerView.VERTICAL, false)
    val users = ArrayList<User>()

    users.add(User("John", "USA"))

    val adapter = CustomAdapter(users)

    recyclerView.adapter = adapter

    fab.setOnClickListener {
        val dialog = Dialog(this)
        Toast.makeText(this, "It's working...", Toast.LENGTH_LONG).show()
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE)
        dialog.setContentView(R.layout.dialog_add)
        dialog.setTitle("Add person")
        dialog.setCancelable(false)

        val nameText = dialog.findViewById(R.id.name) as EditText
        val addressText = dialog.findViewById(R.id.address) as EditText
        val btnAdd = dialog.findViewById(R.id.btn_ok) as Button
        val btnCancel = dialog.findViewById(R.id.btn_cancel) as Button

        btnAdd.setOnClickListener{
            users.add(User(nameText.text.toString(), addressText.text.toString()))
            adapter.notifyDataSetChanged()
            dialog.dismiss()
        }
        btnCancel.setOnClickListener {
            dialog.dismiss()
        }
    //add this line 
     //Call show() method to show dialog 
  dialog.show()
    }
}