安卓Kotlin按钮+警告对话框+列表

Question

我有这段代码：

var firstKitList = mutableListOf<String>("test", "potato", "another item")

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

    val mainKitList = kitListView
    val mainListViewAdapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, firstKitList)
    mainKitList.adapter = mainListViewAdapter

    newKitListBtn.setOnClickListener {
        // Handler code here.
        val intent = Intent(this, NewKitListActivity::class.java)
        startActivity(intent);
    }
}

对于这个布局， 当我点击按钮时，如何让警示框弹出来，让我添加一个名称（就像我要添加到那个列表中的项目一样），然后进入下一个活动？（这部分已经创建好了，您可以在代码中看到）

- TimonYT

---

在 OnClickListener 中创建一个 AlertDialog，并在完成后启动活动？ - creativecreatorormaybenot

Answer 1

我创建了一个函数，其中包含带有EditText的警报对话框。当您点击保存时，名称将存储在mutableList中并重定向到新的活动。

修改后的代码

var firstKitList = mutableListOf<String>("test", "potato", "another item")
// Mutable List for holding names
val nameList = mutableListOf<String>()

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

    val mainKitList = kitListView
    val mainListViewAdapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, firstKitList)
    mainKitList.adapter = mainListViewAdapter

    newKitListBtn.setOnClickListener {
        // Show Alert Dialog
        showNewNameDialog()              
    }
}

警告对话框函数

fun showNewNameDialog() {
        val dialogBuilder = AlertDialog.Builder(this)
        val inflater = this.layoutInflater
        val dialogView = inflater.inflate(R.layout.custom_dialog, null)
        dialogBuilder.setView(dialogView)

        val editText = dialogView.findViewById<EditText>(R.id.editTextName) 

        dialogBuilder.setTitle("Custom dialog")
        dialogBuilder.setMessage("Enter Name Below")
        dialogBuilder.setPositiveButton("Save", { dialog, whichButton ->
            //do something with edt.getText().toString();

           // Add Name in list
            nameList.add(editText.text.toString())
            // Handler code here.
            val intent = Intent(this, NewKitListActivity::class.java)
            startActivity(intent);
        })

        dialogBuilder.setNegativeButton("Cancel", { dialog, whichButton ->
            //pass
        })
        val b = dialogBuilder.create()
        b.show()
    }

自定义对话框布局：custom_dialog.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="10dp"
    android:orientation="vertical">

    <EditText
        android:id="@+id/editTextName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="text" />

</LinearLayout>

- Rajesh Dalsaniya

Answer 2

我使用 Kotlin 的特性将代码从 Rajesh Dalsaniya's answer 更改为更加简洁：

fun showNewNameDialog(activity: Activity) {
    AlertDialog.Builder(activity).apply {
        val dialogView = activity.layoutInflater.inflate(R.layout.custom_dialog, null)
        val editText = dialogView.findViewById<EditText>(R.id.editTextName)

        setView(dialogView)

        setTitle("Custom dialog")
        setMessage("Enter Name Below")
        setPositiveButton("Save") { _, _ ->
            //do something with edt.getText().toString();

            // Add Name in list
            activity.nameList.add(editText.text.toString())
            // Handler code here.
            val intent = Intent(activity, NewKitListActivity::class.java)
            activity.startActivity(intent);
        }

        setNegativeButton("Cancel") { _, _ ->
            //pass
        }
    }.create().show()
}

XML 保持不变：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="10dp"
    android:orientation="vertical">

    <EditText
        android:id="@+id/editTextName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="text" />
</LinearLayout>

- Christian