重要知识点,对下拉列表的选项设置监听事件。
public class MainActivity extends AppCompatActivity {
private Spinner sp;
private Spinner sp2;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sp = findViewById(R.id.sp);
sp2= findViewById(R.id.sp2);
initsp();
initsp2();
}
private void initsp() {
String[] strArr = new String[]{"北京", "邯郸", "永年"};
ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item, strArr);
//构造下拉列表三个参数的含义:1、上下文(this)2、列表项的layout资源ID3、下拉列表显示内容的文本
sp.setAdapter(adapter);
}
private void initsp2(){
List<Map<String,Object>> list=new ArrayList<Map<String, Object>>();
Map<String,Object> map1=new HashMap<>();
map1.put("icon",R.mipmap.ic_launcher);
map1.put("text","哈哈哈");
list.add(map1);
Map<String,Object> map2=new HashMap<>();
map2.put("icon",R.mipmap.ic_launcher);
map2.put("text","....");
list.add(map2);
SimpleAdapter adapter=new SimpleAdapter(this,list,R.layout.checkbox,new String[]{"icon","text"},new int[]{R.id.iv,R.id.tv});
sp2.setAdapter(adapter);
sp2.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Spinner spinner= (Spinner) parent;
Map<String,Object> item= (Map<String, Object>) spinner.getItemAtPosition(position);
setTitle((CharSequence) item.get("text"));
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
}
新建个xml文件对spinner格式进行定义