如何创建下拉列表?

转轮xml:

<Spinner
android:id="@+id/spinner"
android:layout_width="wrap_content"
android:layout_height="match_parent" />

java:

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener{


private Spinner spinner;
private static final String[] paths = {"item 1", "item 2", "item 3"};


@Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main_layout);


spinner = (Spinner)findViewById(R.id.spinner);
ArrayAdapter<String>adapter = new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_spinner_item,paths);


adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(adapter);
spinner.setOnItemSelectedListener(this);


}


@Override
public void onItemSelected(AdapterView<?> parent, View v, int position, long id) {


switch (position) {
case 0:
// Whatever you want to happen when the first item gets selected
break;
case 1:
// Whatever you want to happen when the second item gets selected
break;
case 2:
// Whatever you want to happen when the thrid item gets selected
break;


}
}


@Override
public void onNothingSelected(AdapterView<?> parent) {
// TODO Auto-generated method stub
}


}

简单的/优雅的/我怎么做的:

预览:

XML:

<Spinner
android:id="@+id/spinner1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@android:drawable/btn_dropdown"
android:spinnerMode="dropdown"/>

spinnerMode设置为dropdown是android进行下拉的方式。(https://developer.android.com/reference/android/widget/Spinner#attr_android:spinnerMode)

Java:

//get the spinner from the xml.
Spinner dropdown = findViewById(R.id.spinner1);
//create a list of items for the spinner.
String[] items = new String[]{"1", "2", "three"};
//create an adapter to describe how the items are displayed, adapters are used in several places in android.
//There are multiple variations of this, but this is the basic variant.
ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_dropdown_item, items);
//set the spinners adapter to the previously created one.
dropdown.setAdapter(adapter);

文档:

1. 你可以使用setOnItemSelectedListener。(https://developer.android.com/guide/topics/ui/controls/spinner.html#SelectListener)
2. 您可以从xml中添加字符串列表。(https://developer.android.com/guide/topics/ui/controls/spinner.html#Populate)
3. 这个视图有一个appCompat版本。(https://developer.android.com/reference/androidx/appcompat/widget/AppCompatSpinner)

这个代码对我来说很好，希望它也能帮助到你。

。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="1dip" >
<TextView
android:id="@+id/spinnerItem"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="2dp"
android:textSize="12sp" >
</TextView>
</RelativeLayout>

details.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginBottom="20dp"
android:background="#FF00FF">
<Spinner
android:id="@+id/dropStatus"
android:layout_width="250dp"
android:layout_height="30dp"
android:layout_marginBottom="7dp"
android:drawSelectorOnTop="true"/>
</LinearLayout>

适配器类:

import java.util.ArrayList;


import android.content.Context;
import android.content.res.Resources;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;


public class StatusAdapter extends ArrayAdapter<StatusBean> {


private Context context;
private ArrayList<StatusBean> statuses;
public Resources res;
StatusBean currRowVal = null;
LayoutInflater inflater;


public StatusAdapter(Context context,
int textViewResourceId, ArrayList<StatusBean> statuses,
Resources resLocal) {
super(context, textViewResourceId, statuses);
this.context = context;
this.statuses = statuses;
this.res = resLocal;
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}


@Override
public View getDropDownView(int position, View convertView, ViewGroup parent) {
return getCustomView(position, convertView, parent);
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {
return getCustomView(position, convertView, parent);
}


public View getCustomView(int position, View convertView, ViewGroup parent) {
View row = inflater.inflate(R.layout.status_item, parent, false);
currRowVal = null;
currRowVal = (StatusBean) statuses.get(position);
TextView label = (TextView) row.findViewById(R.id.spinnerItem);
if (position == 0) {
label.setText("Please select status");
} else {
label.setText(currRowVal.getStatus());
}


return row;
}
}

StatusBean类:

public class StatusBean {


private String status;
private String statusCode;


public StatusBean() {
}


public StatusBean(String status,
String statusCode) {
this.status = status;
this.statusCode = statusCode;
}


public String getStatus() {
return status;
}


public void setStatus(String status) {
this.status =  status;
}


public String getStatusCode() {
return statusCode;
}


public void setStatusCode(String statusCode) {
this.statusCode = statusCode;
}
}

活动班级:

在onCreate方法内部:

static ArrayList<StatusBean> STATUS_LIST = new ArrayList<StatusBean>();


for(int i=0;i<=10;i++) {
STATUS_LIST.add(new StatusBean(“Status ”+i, “Stattus ”+i));
}


final Spinner  dropStatus = (Spinner)findViewById(R.id.dropStatus);
Resources res = getResources();
StatusAdapter adapter = new StatusAdapter(this, R.layout.item, SessionData. STATUS_LIST, res);
dropStatus.setAdapter(adapter);

下面是它的代码。

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >


<Spinner
android:id="@+id/static_spinner"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:layout_marginTop="20dp" />


<Spinner
android:id="@+id/dynamic_spinner"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />

strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">Ahotbrew.com - Dropdown</string>
<string-array name="brew_array">
<item>Cappuccino</item>
<item>Espresso</item>
<item>Mocha</item>
<item>Caffè Americano</item>
<item>Cafe Zorro</item>
</string-array>

MainActivity

Spinner staticSpinner = (Spinner) findViewById(R.id.static_spinner);


// Create an ArrayAdapter using the string array and a default spinner
ArrayAdapter<CharSequence> staticAdapter = ArrayAdapter
.createFromResource(this, R.array.brew_array,
android.R.layout.simple_spinner_item);


// Specify the layout to use when the list of choices appears
staticAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);


// Apply the adapter to the spinner
staticSpinner.setAdapter(staticAdapter);


Spinner dynamicSpinner = (Spinner) findViewById(R.id.dynamic_spinner);


String[] items = new String[] { "Chai Latte", "Green Tea", "Black Tea" };


ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, items);


dynamicSpinner.setAdapter(adapter);


dynamicSpinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view,
int position, long id) {
Log.v("item", (String) parent.getItemAtPosition(position));
}


@Override
public void onNothingSelected(AdapterView<?> parent) {
// TODO Auto-generated method stub
}
});

这个例子来自 http://www.ahotbrew.com/android-dropdown-spinner-example/ < / p >

你需要一个Spinner。下面是一个例子:

spinner_1 = (Spinner) findViewById(R.id.spinner1);
spinner_1.setOnItemSelectedListener(this);
List<String> list = new ArrayList<String>();
list.add("RANJITH");
list.add("ARUN");
list.add("JEESMON");
list.add("NISAM");
list.add("SREEJITH");
list.add("SANJAY");
list.add("AKSHY");
list.add("FIROZ");
list.add("RAHUL");
list.add("ARJUN");
list.add("SAVIYO");
list.add("VISHNU");


ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, list);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner_1.setAdapter(adapter);




spinner_2 = (Spinner) findViewById(R.id.spinner_two);
spinner_2.setOnItemSelectedListener(this);
List<String> city = new ArrayList<String>();
city.add("KASARGOD");
city.add("KANNUR");
city.add("THRISSUR");
city.add("KOZHIKODE");
city.add("TRIVANDRUM");
city.add("ERNAMKULLAM");
city.add("WAYANAD");
city.add("PALAKKAD");
city.add("ALAPUZHA");
city.add("IDUKKI");
city.add("KOTTAYAM");
city.add("PATHANAMTHITTA");
city.add("KOLLAM");
city.add("MALAPPURAM");
ArrayAdapter<String> adapter2 = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, city);
adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner_2.setAdapter(adapter2);

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position,
long id) {
// TODO Auto-generated method stub
Toast.makeText(this, "YOUR SELECTION IS : " + parent.getItemAtPosition(position).toString(), Toast.LENGTH_SHORT).show();




}


@Override
public void onNothingSelected(AdapterView<?> parent) {
// TODO Auto-generated method stub


}

你也可以使用AppCompatSpinner小部件:

<android.support.v7.widget.AppCompatSpinner
android:id="@+id/spinner_order_type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:backgroundTint="@color/red"/>

在Activity类内部:

AppCompatSpinner spinOrderType = (AppCompatSpinner) findViewById(R.id.spinner_order_type);
List<String> categories = new ArrayList<String>();
categories.add(getString(R.string.label_table_order));
categories.add(getString(R.string.label_take_away));


ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(mContext,
R.layout.layout_spinner_item, categories);
dataAdapter.setDropDownViewResource(R.layout.layout_spinner_item);
spinOrderType.setAdapter(dataAdapter);
spinOrderType.setSelection(0);


spinOrderType.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long l) {
String item = parent.getItemAtPosition(position).toString();
Log.d(TAG, item);
}


@Override
public void onNothingSelected(AdapterView<?> adapterView) {


}
});

layout_spinner_item.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:tools="http://schemas.android.com/tools"
android:gravity="left"
android:textSize="@dimen/text.size.large"
android:textColor="@color/text.link"
android:padding="@dimen/margin.3" />

试试这个…

<string-array name="names">


<item></item>
<item>By Bus</item>
<item>By Train</item>
<item>By Van</item>
<item>By Bike</item>
</string-array>




String travel_type;




ArrayAdapter<String> myAdapter = new ArrayAdapter(AddNew_Trip.this,android.R.layout.simple_list_item_1, getResources().getStringArray(R.array.names));
myAdapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
mySpinner.setAdapter(myAdapter);


mySpinner.setOnItemSelectedListener(
new AdapterView.OnItemSelectedListener() {


@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
travel_type = String.valueOf(adapterView.getItemAtPosition(i));
//Toast.makeText(Plan_Trip.this, travel_type, Toast.LENGTH_SHORT).show();
}


@Override
public void onNothingSelected(AdapterView<?> adapterView) {


}


}
);
}

试试这个:

package example.spin.spinnerexample;


import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;


public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener{


String[] bankNames={"BOI","SBI","HDFC","PNB","OBC"};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Getting the instance of Spinner and applying OnItemSelectedListener on it
Spinner spin = (Spinner) findViewById(R.id.simpleSpinner);
spin.setOnItemSelectedListener(this);


//Creating the ArrayAdapter instance having the bank name list
ArrayAdapter aa = new ArrayAdapter(this,android.R.layout.simple_spinner_item,bankNames);
aa.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
//Setting the ArrayAdapter data on the Spinner
spin.setAdapter(aa);
}




//Performing action onItemSelected and onNothing selected
@Override
public void onItemSelected(AdapterView<?> arg0, View arg1, int position,long id) {
Toast.makeText(getApplicationContext(), bankNames[position], Toast.LENGTH_LONG).show();
}


@Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub


}
}

activity_main.xml: -

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity">


<Spinner
android:id="@+id/simpleSpinner"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="100dp" />


</RelativeLayout>

在Kotlin中，您可以这样做:

首先，将这些代码放入布局中

   <Spinner
android:id="@+id/spinner"
android:layout_width="wrap_content"
android:layout_height="match_parent"/>

然后你可以在onCreate()在活动作为->

   val spinner = findViewById<Spinner>(R.id.spinner)
val items = arrayOf("500g", "1kg", "2kg")
val adapter = ArrayAdapter<String>(
this,
android.R.layout.simple_spinner_dropdown_item,
items
)
spinner.setAdapter(adapter)

你可以从下拉菜单中获取listener:

 spinner.onItemSelectedListener = object : OnItemSelectedListener {
override fun onItemSelected(
arg0: AdapterView<*>?,
arg1: View?,
arg2: Int,
arg3: Long
) {
// Do what you want
val items = spinner.selectedItem.toString()
            

}


override fun onNothingSelected(arg0: AdapterView<*>?) {}
}

您可以通过以下简单的步骤创建旋转器

首先在XML中创建旋转器

<Spinner
android:id="@+id/select"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textColor="#070707"></Spinner>

现在在值中创建字符串arary

 <string-array name="itemselect">
<item>Repurchase</item>
<item>Coupons</item>
</string-array>

现在在Java文件中初始化

public class MemberCart_Activity extends AppCompatActivity {


Spinner select;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_member_cart);


 

select=findViewById(R.id.select);
ArrayAdapter<String> myadapter=new ArrayAdapter<String>(Main_Activity.this,android.R.layout.simple_list_item_1,getResources().getStringArray(R.array.itemselect));
myadapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
select.setAdapter(myadapter);

parseInt(binding.inputAge.text.toString()),

新的android资源文件(dropdown_item)在R.layout.dropdown_item中，放置textview在里面。

TextView代码:

`<TextView android:id="@+id/textView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="14sp"
android:text="textView"
android:textColor="@color/black"
android:textSize="16sp"
android:textStyle="bold"
xmlns:android="http://schemas.android.com/apk/res/android"/>`

//绑定适配器并获取值 binding.ddCity.setAdapter(showCity) binding.ddCity.selectedItem.toString() < / p >

创建Spinner inm XML android:条目=“@array / locations" 然后将鼠标悬停在array/locations上并创建资源文件

资源文件应该是 ｀ “新Yorkshire"

    </resources>`

然后

binding.spinner.selectedItem.toString()

要将你的列表动态添加到旋转器中，就像从webservice中添加数组列表中的项目，并将其加载到旋转器中

<androidx.appcompat.widget.AppCompatSpinner
android:id="@+id/catNameSpinner"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:spinnerMode="dropdown"
/>


spinner = findViewById(R.id.catNameSpinner);
ArrayList<String> cat = new ArrayList<>();
cat.add("Choose");


ArrayAdapter<String> spinnerAdapter = new ArrayAdapter<String>
(this,android.R.layout.simple_dropdown_item_1line,cat);
spinner.setAdapter(spinnerAdapter);