如何创建下拉列表?我试过ScrollView,但它不是我所需要的。
当前回答
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);
其他回答
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 class:
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);
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<*>?) {}
}
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>
你需要一个旋转器。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
}
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的下拉方式。(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:
这是基础知识,但还有更多的东西可以通过实验自学。 https://developer.android.com/guide/topics/ui/controls/spinner.html
你可以使用setOnItemSelectedListener。(https://developer.android.com/guide/topics/ui/controls/spinner.html # SelectListener) 您可以从xml中添加字符串列表。(https://developer.android.com/guide/topics/ui/controls/spinner.html #填充) 这个视图有一个appCompat版本。(https://developer.android.com/reference/androidx/appcompat/widget/AppCompatSpinner)
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