Spinner
Spinner是一個列表選擇框,會在用戶選擇后,展示一個列表供用戶進行選擇。Spinner是ViewGroup的間接子類,它和其他的Android控件一樣,數據需要使用Adapter進行封裝。
1,Demo展示圖片

2,布局代碼
//(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="今年的常規賽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>
3,Activity代碼
//MainActivityimport 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;import static com.test.spinner.R.id.simpleAdapter;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(){ // 設置數據集 List<String> list = new ArrayList<>(); list.add("哈登"); list.add("萊昂納德"); list.add("詹姆斯"); list.add("威斯布魯克"); 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" , "萊昂納德" , "詹姆斯" , "威斯布魯克"}; // 設置適配器 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); // 設置監聽器 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 simpleAdapter: mSpinner.setVisibility(View.VISIBLE); mSpinner.setAdapter(mSimpleAdapter); // 設置監聽器 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); }}以上所述是小編給大家介紹的Android中使用Spinner實現下拉列表功能,希望對大家有所幫助,如果大家有任何疑問請給我留言,小編會及時回復大家的。在此也非常感謝大家對武林網網站的支持!
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