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Spinner是下拉弹出框,类似popWindow,但是Spinner有2种模式,dialog + dropdown。dropdown是在spinner的下方显示,dialog是作为一个dialog显示。
package com.cqc.spinneradaptger;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.BaseAdapter;import android.widget.Spinner;import android.widget.TextView;public class MainActivity extends AppCompatActivity { private String[] array = { "item1","item2","item3"}; private Spinner spinner; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); spinner = (Spinner) findViewById(R.id.spinner); spinner.setAdapter(new MyAdapter());//adapter继承BaseAdapter spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView parent, View view, int position, long id) { //获取选中的值 String str1 = (String) parent.getItemAtPosition(position); String str2 = (String) spinner.getItemAtPosition(position); Log.d("tag","str1="+str1+"--str2="+str2); } @Override public void onNothingSelected(AdapterView parent) { parent.setVisibility(View.VISIBLE);//可以不写 } }); } public class MyAdapter extends BaseAdapter{ @Override public int getCount() { return array.length; } @Override public Object getItem(int position) { return array[position]; } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { TextView tv = new TextView(MainActivity.this); tv.setTextSize(20.0f); tv.setText(array[position]); return tv; } }}
官方API:
您为微调框提供的选择可来自任何来源,但必须通过 SpinnerAdapter 来提供,例如,如果选择可通过数组获取,则通过 ArrayAdapter)来提供,如果选择可通过数据库查询获取,则通过 CursorAdapter 来提供。
ArrayAdapteradapter = ArrayAdapter.createFromResource(this,R.array.planets_array, android.R.layout.simple_spinner_item);// Specify the layout to use when the list of choices appearsadapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);// Apply the adapter to the spinnerspinner.setAdapter(adapter);
simple_spinner_dropdown_item
与simple_spinner_item
的区别?
simple_spinner_dropdown_item是给列表用的,item有高度,是android:layout_height="?android:attr/dropdownListPreferredItemHeight"。simple_spinner_item是普通的item,高度是wrap_content
刚打开这个activity,那么这个监听就获取数据了(一般是Array中的第一条数据),而不是必须要手动选择才会获取数。
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView adapterView, View view, int position, long id) { String text = (String) adapterView.getItemAtPosition(position); String text2 = (String) spinner.getSelectedItem(); Log.d(TAG, "setOnItemSelectedListener text=" + text); Log.d(TAG, "setOnItemSelectedListener text2=" + text2); } @Override public void onNothingSelected(AdapterView adapterView) { }});
除了在监听中获取spinner选中的数据外,我们还可以这样:
String text = (String) spinner.getSelectedItem();
android:backgroundTint="@color/blue1"android:popupBackground="@color/colorPrimary"