我目前正在尝试使用一些不同的教程在Android应用程序中实现蓝牙连接,并且遇到了尝试将检测到的配对设备添加到ListView以供用户选择的问题。
目前正在下面的行中抛出错误“无法解析符号项”,但我不知道用什么替换项目或者如果这是唯一的问题。 itemsAdapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,items);
如果有人可以在Java代码中更正我的语法,我将非常感激。
谢谢!
Java代码
package com.example.khite.wheelnav;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import java.util.Set;
public class ConnectActivity extends ActionBarActivity {
private static final int REQUEST_ENABLE_BT = 1234;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_connect);
// Create Bluetooth Adapter
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
Intent intent;
intent = new Intent(this, NoBluetoothActivity.class);
startActivity(intent);
}
// Enable Bluetooth
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
// Create an Array Adapter to Add Devices to
ArrayAdapter<String> itemsAdapter;
itemsAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, items);
//Query Paired Devices
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
// If there are paired devices
if (pairedDevices.size() > 0) {
// Loop through paired devices
for (BluetoothDevice device : pairedDevices) {
// Add the name and address to an array adapter to show in a ListView
itemsAdapter.add(device.getName() + "\n" + device.getAddress());
}
}
// Add Paired Devices to a List View
ListView listView = (ListView) findViewById(R.id.listView);
listView.setAdapter(itemsAdapter);
}
public void openChooseFunctionActivity(View view){
//open choose function activity
Intent intent;
intent = new Intent(this, ChooseFunctionActivity.class);
startActivity(intent);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
XML代码
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context="com.example.khite.wheelnav.ConnectActivity">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Continue"
android:id="@+id/button2"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:onClick="openChooseFunctionActivity"
android:background="#ff8180fd"
android:textColor="#ff000000" />
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/listView"
android:layout_centerHorizontal="true" />
</RelativeLayout>
答案 0 :(得分:0)
“items”根本没有初始化。您必须传递String []或List&lt; String&gt; object作为ArrayAdapter构造函数的最后一个参数。
“无法解析符号x”通常表示无法找到变量x。
答案 1 :(得分:0)
首先初始化您的项目集合,然后初始化适配器
//Query Paired Devices
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
// If there are paired devices
List<String> items = new ArrayList<String>();
if (pairedDevices.size() > 0) {
// Loop through paired devices
for (BluetoothDevice device : pairedDevices) {
// Add the name and address to an array adapter to show in a ListView
items.add(device.getName() + "\n" + device.getAddress());
}
}
// Create an Array Adapter to Add Devices to
ArrayAdapter<String> itemsAdapter;
itemsAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, items);