Spinner的基本用法Demo

代码

kotlin

//点击协议选择
        val protocols = resources.getStringArray(R.array.protocol)
        val adapter = ArrayAdapter(this, R.layout.item_protocol, protocols)
        viewBinding.serverProtocolSelect.adapter = adapter
        viewBinding.serverProtocolSelect.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
            override fun onNothingSelected(p0: AdapterView<*>?) {}

            override fun onItemSelected(adapterView: AdapterView<*>?, view: View?, pos: Int, id: Long) {
                when (protocols[pos]) {
                    "https" -> ServiceConfig.is_service_https = true
                    else -> ServiceConfig.is_service_https = false
                }
            }
        }

​​另一种写法(从sharedPreferences)中择取:​​

//模式选择
        val modes = resources.getStringArray(R.array.mode)
        val modeNum = modes.indexOf(ServiceConfig.mode_change)
        val adapter = ArrayAdapter(this, R.layout.item_mode, modes)
        viewBinding.chooseModeSpinner.adapter = adapter
        viewBinding.chooseModeSpinner.setSelection(modeNum)//设置系统原模式
        viewBinding.chooseModeSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
            override fun onNothingSelected(p0: AdapterView<*>?) {}

            override fun onItemSelected(adapterView: AdapterView<*>?, view: View?, pos: Int, id: Long) {
                selectedItem = modes[pos]
            }
        }

Layout
​​​layout​​

<Spinner
    android:id="@+id/server_protocol_select"
    style="@style/Spinner.LittleList"
    android:entries="@array/protocol" />

<style name="Spinner.LittleList">
    <item name="android:layout_width">match_parent</item>
    <item name="android:layout_height">@dimen/spinner.list</item>
    <item name="android:overlapAnchor">false</item>
    <item name="android:spinnerMode">dropdown</item>
    <item name="android:theme">@style/SpinnerColor</item>
</style>

​​item​​

<?xml version="1.0" encoding="utf-8"?>
<TextView style="@style/Spinner.ListItem" />

<style name="Spinner.ListItem">
    <item name="android:layout_width">match_parent</item>
    <item name="android:layout_height">@dimen/spinner.list</item>
    <item name="android:background">@drawable/settings_selector_protocol</item>
    <item name="android:gravity">center</item>
    <item name="android:textColor">@color/white</item>
    <item name="android:textSize">@dimen/tip</item>
    <item name="android:textStyle">bold</item>
    <item name="android:padding">@dimen/spinner.padding</item>
    <item name="android:text">123</item>
</style>

​​array​​

<resources>
    <string-array name="protocol">
        <item>http</item>
        <item>https</item>
    </string-array>
</resources>

示例:

一些其他的要点

​​更改spinner 箭头颜色​​

//在styles 里面添加一个新的style 可以叫 SpinnerStyle
<style name="SpinnerStyle">
    <item name="colorControlNormal">#ddffffff</item> <!--改变了spinner的颜色  -->
</style>

然后在layout中让相应的spinner 引用这个theme

<Spinner
    android:id="@+id/sp_homefragment_plane_name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:theme="@style/SpinnerStyle"
    android:entries="@array/breeze"
    android:dropDownWidth="match_parent"
</Spinner>

​​从标签底部向下弹出​​

android:overlapAnchor="false"