Android中使用Spinner实现下拉列表

Demo展示图片

布局代码

//(layout)activity_main
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.test.spinner.MainActivity">

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:textSize="20sp"
android:layout_margin="10dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="今年的常规赛MVP："/>

<TextView
android:id="@+id/text"
android:textSize="20sp"
android:layout_marginTop="10dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>

<Spinner
android:visibility="gone"
android:id="@+id/spinner"
android:layout_marginLeft="10dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</Spinner>
</LinearLayout>
-------------------------------------------------------------------
//(layout)item
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical">

<ImageView
android:id="@+id/imageView"
android:layout_width="80dp"
android:layout_height="80dp"/>

<TextView
android:id="@+id/textView"
android:layout_marginLeft="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>

</LinearLayout>

Activity代码

//MainActivity
import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.SimpleAdapter;
import android.widget.Spinner;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MainActivity extends AppCompatActivity {

private Context mContext = MainActivity.this;
private Spinner mSpinner;
private ArrayAdapter<String> mArrayAdapter;
private TextView mTextView;
private SimpleAdapter mSimpleAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
initData();
}

private void initView(){
mSpinner = (Spinner) findViewById(R.id.spinner);
mTextView = (TextView) findViewById(R.id.text);
}

private void initData(){
// 设置数据集
List<String> list = new ArrayList<>();
list.add("哈登");
list.add("莱昂纳德");
list.add("詹姆斯");
list.add("威斯布鲁克");

List<Map<String ,Object>> maps = new ArrayList<>();
int[] icon = {R.mipmap.pic1 , R.mipmap.pic2, R.mipmap.pic3, R.mipmap.pic4};
String[] iconName = {"哈登" , "莱昂纳德" , "詹姆斯" , "威斯布鲁克"};

// 设置适配器
mArrayAdapter = new ArrayAdapter<>(mContext ,
android.R.layout.simple_spinner_item , list);
mArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

mSimpleAdapter = new SimpleAdapter(mContext,
maps , R.layout.item , new String[]{"image" , "text"} , new int[]{R.id.imageView ,R.id.textView});

for(int i = 0 ; i < icon.length ; i++){
Map<String ,Object> map = new HashMap<>();
map.put("image", icon[i]);
map.put("text" , iconName[i]);
maps.add(map);
}
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main , menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()){
case R.id.arrayAdapter:
mSpinner.setVisibility(View.VISIBLE);
mSpinner.setAdapter(mArrayAdapter);
// 设置监听器
mSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int position, long id) {
mTextView.setText(mArrayAdapter.getItem(position));
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {

}
});

break;

case R.id.simpleAdapter:
mSpinner.setVisibility(View.VISIBLE);
mSpinner.setAdapter(mSimpleAdapter);
// 设置监听器
mSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int position, long id) {
mTextView.setText(mSimpleAdapter.getItem(position)+"");
}

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

}
});

break;

default:
break;
}
return super.onOptionsItemSelected(item);
}
}