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yayun0516 · 更新于 2018-11-28 11:00:43

Android 实战简易教程-第二枪(Spinner 下拉级联效果)

一、实现功能

废话不多说,直接上代码

strings.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, Hello!</string>
    <string name="app_name"></string>
    <string-array name="province">
        <item >江苏省</item>
        <item >山东省</item>
        <item >浙江省</item>
    </string-array>
</resources>

看一下布局文件 main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="horizontal" >

        <Spinner
            android:id="@+id/spinner1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:entries="@array/province"/>

        <Spinner
            android:id="@+id/spinner2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </LinearLayout>

    <TextView
        android:id="@+id/text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </TextView>

</LinearLayout>

MainActivity 代码如下:

package org.yayun.demo;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnFocusChangeListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;

public class MainActivity extends Activity {
    private Spinner spinner1;
    private Spinner spinner2;
    private TextView textView;
    private String[][] dataStrings = { { "南京市", "徐州市", "苏州市", "泰州市", "淮安市", },
            { "济南市", "威海市", "临沂市", }, { "杭州市", "宁波市", "嘉兴市", }, };
    private ArrayAdapter<CharSequence> adapter = null;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState); // 生命周期方法
        super.setContentView(R.layout.main); // 设置要使用的布局管理器
        spinner1 = (Spinner) findViewById(R.id.spinner1);
        spinner2 = (Spinner) findViewById(R.id.spinner2);
        textView = (TextView) findViewById(R.id.text);
        spinner1.setOnItemSelectedListener(new OnItemSelectedListener() {

            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                adapter = new ArrayAdapter<CharSequence>(MainActivity.this,
                        android.R.layout.simple_spinner_item,
                        dataStrings[position]);//根据position确定第二个spinner中要填充的数据
                adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);//设置显示样式
                spinner2.setAdapter(adapter);

            }

            public void onNothingSelected(AdapterView<?> parent) {
                // TODO Auto-generated method stub

            }
        });

    }
}

运行实例:

二、实现监听

修改 MainActivity.java 代码:

package org.yayun.demo;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnFocusChangeListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;

public class MainActivity extends Activity {
    private Spinner spinner1;
    private Spinner spinner2;
    private TextView textView;
    private String[][] dataStrings = { { "南京市", "徐州市", "苏州市", "泰州市", "淮安市", },
            { "济南市", "威海市", "临沂市", }, { "杭州市", "宁波市", "嘉兴市", }, };
    private ArrayAdapter<CharSequence> adapter = null;
    String string1;
    String string2;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState); // 生命周期方法
        super.setContentView(R.layout.main); // 设置要使用的布局管理器
        spinner1 = (Spinner) findViewById(R.id.spinner1);
        spinner2 = (Spinner) findViewById(R.id.spinner2);
        textView = (TextView) findViewById(R.id.text);

        spinner1.setOnItemSelectedListener(new OnItemSelectedListener() {

            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                adapter = new ArrayAdapter<CharSequence>(MainActivity.this,
                        android.R.layout.simple_spinner_item,
                        dataStrings[position]);// 根据position确定第二个spinner中要填充的数据
                adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);// 设置显示样式
                spinner2.setAdapter(adapter);
                string1 = parent.getItemAtPosition(position).toString();// 获取当前显示省份

            }

            public void onNothingSelected(AdapterView<?> parent) {
                // TODO Auto-generated method stub

            }
        });
        spinner2.setOnItemSelectedListener(new OnItemSelectedListener() {

            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                string2 = parent.getItemAtPosition(position).toString();// 获取当前显示省份
                textView.setText(string1 + string2);

            }

            public void onNothingSelected(AdapterView<?> parent) {
                // TODO Auto-generated method stub

            }
        });

    }
}

运行实例如下:

总结

1.string1 = parent.getItemAtPosition(position).toString();// 获取当前显示省份

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