Android OnclickListener（）不在选项卡上工作
我正在进行基于蓝牙的项目。我正在使用标签来包含不同的页面。当包含按钮onclick listener时，应用程序崩溃。我引用了sdk中的蓝牙聊天。在Setupchat（）中，我试图识别按钮并分配onclicklisteners。但应用程序在onclicklistner上崩溃了。我检查了logcat，它显示空指针异常。这是logcat输出Android OnclickListener（）不在选项卡上工作,android,android-fragments,bluetooth,Android,Android Fragments,Bluetooth,我正在进行基于蓝牙的项目。我正在使用标签来包含不同的页面。当包含按钮onclick listener时，应用程序崩溃。我引用了sdk中的蓝牙聊天。在Setupchat（）中，我试图识别按钮并分配onclicklisteners。但应用程序在onclicklistner上崩溃了。我检查了logcat，它显示空指针异常。这是logcat输出 08-11 16:25:08.003: E/AndroidRuntime(16481): FATAL EXCEPTION: main 08-11 16:25:0
08-11 16:25:08.003: E/AndroidRuntime(16481): FATAL EXCEPTION: main
08-11 16:25:08.003: E/AndroidRuntime(16481): Process: com.dispenser, PID: 16481
08-11 16:25:08.003: E/AndroidRuntime(16481): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.dispenser/com.dispenser.MainActivity}: java.lang.NullPointerException
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2198)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.os.Handler.dispatchMessage(Handler.java:102)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.os.Looper.loop(Looper.java:136)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.ActivityThread.main(ActivityThread.java:5086)
08-11 16:25:08.003: E/AndroidRuntime(16481): at java.lang.reflect.Method.invokeNative(Native Method)
08-11 16:25:08.003: E/AndroidRuntime(16481): at java.lang.reflect.Method.invoke(Method.java:515)
08-11 16:25:08.003: E/AndroidRuntime(16481): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
08-11 16:25:08.003: E/AndroidRuntime(16481): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
08-11 16:25:08.003: E/AndroidRuntime(16481): at dalvik.system.NativeStart.main(Native Method)
08-11 16:25:08.003: E/AndroidRuntime(16481): Caused by: java.lang.NullPointerException
08-11 16:25:08.003: E/AndroidRuntime(16481): at com.dispenser.MainActivity.setupChat(MainActivity.java:223)
08-11 16:25:08.003: E/AndroidRuntime(16481): at com.dispenser.MainActivity.onStart(MainActivity.java:195)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1194)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.Activity.performStart(Activity.java:5258)
08-11 16:25:08.003: E/AndroidRuntime(16481): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2171)
08-11 16:25:08.003: E/AndroidRuntime(16481): ... 11 more
package com.dispenser;
import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.Activity;
import android.app.FragmentTransaction;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.dispenser.adapter.TabsPagerAdapter;
public class MainActivity extends FragmentActivity implements ActionBar.TabListener, OnClickListener {
private ViewPager viewPager;
private TabsPagerAdapter mTabAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Diagnostic", "Set" ,"Settings"};
// Debugging
private static final String TAG = "Main";
private static final boolean D = true;
// Message types sent from the BluetoothChatService Handler
public static final int MESSAGE_STATE_CHANGE = 1;
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
public static final int MESSAGE_DEVICE_NAME = 4;
public static final int MESSAGE_TOAST = 5;
// Key names received from the BluetoothChatService Handler
public static final String DEVICE_NAME = "device_name";
public static final String TOAST = "toast";
// Intent request codes
private static final int REQUEST_CONNECT_DEVICE = 1;
private static final int REQUEST_ENABLE_BT = 2;
// Layout Views
//private TextView mTitle;
private EditText mPS1,mPS2,mPS3,mFT,mFW,valve1,valve2,sPS1,sPS2,sPS3;
private Button mSendButtonOn,mEnable,mDisable,mSet;
private Button mSendButtonOff;
// Name of the connected device
private String mConnectedDeviceName;
// String buffer for outgoing messages
private StringBuffer mOutStringBuffer;
// Local Bluetooth adapter
private BluetoothAdapter mBluetoothAdapter;
// Member object for the chat services
private ChatService mChatService;
@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (D) {
Log.e(TAG, "+++ ON CREATE +++");
}
// Set up the window layout
//requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
setContentView(R.layout.activity_main);
// getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE,
// R.layout.custom_title);
// Set up the custom title
// mTitle = (TextView) findViewById(R.id.title_left_text);
// mTitle.setText(R.string.app_name);
// mTitle = (TextView) findViewById(R.id.title_right_text);
// Get local Bluetooth adapter
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
// If the adapter is null, then Bluetooth is not supported
if (mBluetoothAdapter == null) {
Toast.makeText(this, "Bluetooth is not available",
Toast.LENGTH_LONG).show();
finish();
return;
}
// Initialization
viewPager = (ViewPager) findViewById(R.id.pager);
actionBar = getActionBar();
mTabAdapter = new TabsPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(mTabAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Adding Tabs
for (String tab_name : tabs) {
actionBar.addTab(actionBar.newTab().setText(tab_name)
.setTabListener(this));
}
/**
* on swiping the viewpager make respective tab selected
* */
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageSelected(int position) {
// on changing the page
// make respected tab selected
actionBar.setSelectedNavigationItem(position);
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
@Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
// on tab selected
// show respected fragment view
viewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.scan:
// Launch the DeviceListActivity to see devices and do scan
Intent serverIntent = new Intent(this, DeviceListActivity.class);
startActivityForResult(serverIntent, REQUEST_CONNECT_DEVICE);
return true;
case R.id.discoverable:
// Ensure this device is discoverable by others
ensureDiscoverable();
return true;
}
return false;
}
@Override
public void onStart() {
super.onStart();
if (D) {
Log.e(TAG, "++ ON START ++");
}
// If BT is not on, request that it be enabled.
// setupChat() will then be called during onActivityResult
if (!mBluetoothAdapter.isEnabled()) {
Intent enableIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
// Otherwise, setup the chat session
} else {
if (mChatService == null) {
setupChat();
}
}
}
private void setupChat() {
mSet=(Button) findViewById(R.id.setBtn);
Log.d(TAG, "setupChat()");
// Diagnostic
mPS1=(EditText) findViewById(R.id.ps1);
mPS2=(EditText) findViewById(R.id.ps2);
mPS3=(EditText) findViewById(R.id.ps3);
mFT=(EditText) findViewById(R.id.ft);
mFW=(EditText) findViewById(R.id.fw);
valve1=(EditText) findViewById(R.id.valve1);
valve2=(EditText) findViewById(R.id.valve2);
//Set
sPS1=(EditText) findViewById(R.id.pressure1);
sPS2=(EditText) findViewById(R.id.pressure2);
sPS3=(EditText) findViewById(R.id.pressure3);
// mSet.setOnClickListener(MainActivity.this);
// Preference
// mSendButtonOff.setOnClickListener(MainActivity.this);
// Initialize the BluetoothChatService to perform bluetooth connections
mChatService = new ChatService(this, mHandler);
// Initialize the buffer for outgoing messages
mOutStringBuffer = new StringBuffer("");
}
@Override
public synchronized void onResume() {
super.onResume();
if (D) {
Log.e(TAG, "+ ON RESUME +");
}
// Performing this check in onResume() covers the case in which BT was
// not enabled during onStart(), so we were paused to enable it...
// onResume() will be called when ACTION_REQUEST_ENABLE activity
// returns.
if (mChatService != null) {
// Only if the state is STATE_NONE, do we know that we haven't
// started already
if (mChatService.getState() == ChatService.STATE_NONE) {
// Start the Bluetooth chat services
mChatService.start();
}
}
}
@Override
public synchronized void onPause() {
super.onPause();
if (D) {
Log.e(TAG, "- ON PAUSE -");
}
}
@Override
public void onDestroy() {
super.onDestroy();
// Stop the Bluetooth chat services
if (mChatService != null) {
mChatService.stop();
}
if (D) {
Log.e(TAG, "--- ON DESTROY ---");
}
}
private void ensureDiscoverable() {
if (D) {
Log.d(TAG, "ensure discoverable");
}
if (mBluetoothAdapter.getScanMode() != BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
Intent discoverableIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
discoverableIntent.putExtra(
BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
startActivity(discoverableIntent);
}
}
/**
* Sends a message.
*
* @param message
* A string of text to send.
*/
private void sendMessage(String message) {
// Check that we're actually connected before trying anything
if (mChatService.getState() != ChatService.STATE_CONNECTED) {
Toast.makeText(this, R.string.not_connected, Toast.LENGTH_SHORT)
.show();
return;
}
// Check that there's actually something to send
if (message.length() > 0) {
// XXX !!!
message = message + "\r\n"; // terminate for pc bluetooth spp server
// Get the message bytes and tell the BluetoothChatService to write
byte[] send = message.getBytes();
mChatService.write(send);
// Reset out string buffer to zero and clear the edit text field
mOutStringBuffer.setLength(0);
// mOutEditText.setText(mOutStringBuffer);
}
}
// The Handler that gets information back from the BluetoothChatService
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_STATE_CHANGE:
if (D) {
Log.i(TAG, "MESSAGE_STATE_CHANGE: " + msg.arg1);
}
switch (msg.arg1) {
case ChatService.STATE_CONNECTED:
Toast.makeText(getBaseContext(), R.string.title_connected_to+" " +mConnectedDeviceName, Toast.LENGTH_LONG).show();
// mTitle.append();
// mConversationArrayAdapter.clear();
break;
case ChatService.STATE_CONNECTING:
Toast.makeText(getBaseContext(), R.string.title_connecting, Toast.LENGTH_LONG).show();
break;
case ChatService.STATE_LISTEN:
case ChatService.STATE_NONE:
Toast.makeText(getBaseContext(), R.string.title_not_connected, Toast.LENGTH_LONG).show();
//mTitle.setText();
break;
}
break;
case MESSAGE_WRITE:
byte[] writeBuf = (byte[]) msg.obj;
// construct a string from the buffer
String writeMessage = new String(writeBuf);
// mConversationArrayAdapter.add("Me: " + writeMessage);
break;
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
final String readMessage = new String(readBuf, 0, 50);
// mConversationArrayAdapter.add(mConnectedDeviceName + ": "
// + readMessage);
Runnable done = new Runnable()
{
public void run()
{
String[] b=readMessage.split(",");
for(int i=0;i<b.length;i++){
// Toast.makeText(getBaseContext(), b[i], Toast.LENGTH_SHORT).show();
if(b[i].contains("PS1")){
String[] c=b[i].split("=");
if(c.length==2){
mPS1.setText(c[1]);
}
}
else if(b[i].contains("PS2")){
String[] c=b[i].split("=");
if(c.length==2){
mPS2.setText(c[1]);
}
}
else if(b[i].contains("PS3")){
String[] c=b[i].split("=");
if(c.length==2){
mPS3.setText(c[1]);
}
}
else if(b[i].contains("LPM")){
String[] c=b[i].split("=");
if(c.length==2){
mFW.setText(c[1]);
}
}
else{
}
// mPS1.append(b[i]);
}
}
};
done.run();
break;
case MESSAGE_DEVICE_NAME:
// save the connected device's name
mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
Toast.makeText(getApplicationContext(),
"Connected to " + mConnectedDeviceName,
Toast.LENGTH_SHORT).show();
break;
case MESSAGE_TOAST:
Toast.makeText(getApplicationContext(),
msg.getData().getString(TOAST), Toast.LENGTH_SHORT)
.show();
break;
}
}
};
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (D) {
Log.d(TAG, "onActivityResult " + resultCode);
}
switch (requestCode) {
case REQUEST_CONNECT_DEVICE:
// When DeviceListActivity returns with a device to connect
if (resultCode == Activity.RESULT_OK) {
// Get the device MAC address
String address = data.getExtras().getString(
DeviceListActivity.EXTRA_DEVICE_ADDRESS);
// Get the BLuetoothDevice object
BluetoothDevice device = mBluetoothAdapter
.getRemoteDevice(address);
// Attempt to connect to the device
mChatService.connect(device);
}
break;
case REQUEST_ENABLE_BT:
// When the request to enable Bluetooth returns
if (resultCode == Activity.RESULT_OK) {
// Bluetooth is now enabled, so set up a chat session
setupChat();
} else {
// User did not enable Bluetooth or an error occured
Log.d(TAG, "BT not enabled");
Toast.makeText(this, R.string.bt_not_enabled_leaving,
Toast.LENGTH_SHORT).show();
finish();
}
}
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.setBtn:
if(sPS1.getText().length()!=0){
float pressure1=Float.parseFloat(sPS1.getText().toString());
if(pressure1>0.0F && pressure1<20.0F)
sendMessage("PS1="+pressure1);
}
else{
sPS1.setError("Enter PS1");
}
if(sPS2.getText().length()!=0){
float pressure2=Float.parseFloat(sPS2.getText().toString());
if(pressure2>0.0F && pressure2<20.0F)
sendMessage("PS2="+pressure2);
}
else{
sPS2.setError("Enter PS2");
}
if(sPS3.getText().length()!=0){
float pressure3=Float.parseFloat(sPS3.getText().toString());
if(pressure3>0.0F && pressure3<20.0F)
sendMessage("PS3="+pressure3);
}
else{
sPS3.setError("Enter PS3");
}
break;
default:
break;
}
}
}
package.com分配器；
导入android.annotation.SuppressLint；
导入android.app.ActionBar；
导入android.app.ActionBar.Tab；
导入android.app.Activity；
导入android.app.FragmentTransaction；
导入android.bluetooth.BluetoothAdapter；
导入android.bluetooth.bluetooth设备；
导入android.content.Intent；
导入android.os.Bundle；
导入android.os.Handler；
导入android.os.Message；
导入android.support.v4.app.FragmentActivity；
导入android.support.v4.view.ViewPager；
导入android.util.Log；
导入android.view.Menu；
导入android.view.MenuInflater；
导入android.view.MenuItem；
导入android.view.view；
导入android.view.view.OnClickListener；
导入android.widget.Button；
导入android.widget.EditText；
导入android.widget.Toast；
导入com.dispenser.adapter.TabsPagerAdapter；
公共类MainActivity扩展FragmentActivity实现ActionBar.TablListener、OnClickListener{
私人视页机视页机；
私人TabsPagerAdapter mTabAdapter；
私人ActionBar ActionBar；
//标签标题
私有字符串[]选项卡={“诊断”、“设置”、“设置”}；
//调试
私有静态最终字符串TAG=“Main”；
私有静态最终布尔值D=true；
//从BluetoothChatService处理程序发送的消息类型
公共静态最终int消息_STATE_CHANGE=1；
公共静态最终int消息_READ=2；
公共静态最终int消息_WRITE=3；
公共静态最终int消息\u设备\u名称=4；
公共静态最终int消息_TOAST=5；
//从BluetoothChatService处理程序接收的密钥名称
公共静态最终字符串DEVICE\u NAME=“DEVICE\u NAME”；
公共静态最终字符串TOAST=“TOAST”；
//意图请求代码
专用静态最终int请求\u连接\u设备=1；
私有静态最终整数请求_ENABLE_BT=2；
//布局视图
//私有文本视图mTitle；
私有编辑文本mPS1、mPS2、mPS3、mFT、mFW、valve1、valve2、sPS1、sPS2、sPS3；
私有按钮mSendButtonOn、可菜单、可计量、mSet；
私人按钮mSendButtonOff；
//连接的设备的名称
私有字符串mConnectedDeviceName；
//传出消息的字符串缓冲区
私有字符串缓冲区mOutStringBuffer；
//本地蓝牙适配器
私人蓝牙适配器mBluetoothAdapter；
//聊天室服务的成员对象
私人聊天室服务；
@SuppressLint（“新API”）
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
如果（D）{
Log.e（标记“+++”ON CREATE+++”；
}
//设置窗口布局
//requestWindowFeature（Window.FEATURE\u自定义\u标题）；
setContentView（R.layout.activity_main）；
//getWindow（）.setFeatureInt（Window.FEATURE\u自定义\u标题，
//R.布局、自定义标题）；
//设置自定义标题
//mTitle=（TextView）findViewById（R.id.title\u left\u text）；
//mTitle.setText（R.string.app_name）；
//mTitle=（TextView）findViewById（R.id.title\u right\u text）；
//获取本地蓝牙适配器
mBluetoothAdapter=BluetoothAdapter.getDefaultAdapter（）；
//如果适配器为空，则不支持蓝牙
if（mBluetoothAdapter==null）{
Toast.makeText（此“蓝牙不可用”，
Toast.LENGTH_LONG）.show（）；
完成（）；
返回；
}
//初始化
viewPager=（viewPager）findViewById（R.id.pager）；
actionBar=getActionBar（）；
mTabAdapter=新选项卡SPAGERADAPTER（getSupportFragmentManager（））；
viewPager.setAdapter（mTabAdapter）；
actionBar.setHomeButtonEnabled（假）；
actionBar.setNavigationMode（actionBar.NAVIGATION\u MODE\u选项卡）；
//添加选项卡
用于（字符串选项卡\名称：选项卡）{
actionBar.addTab（actionBar.newTab（）.setText（选项卡名称）
.setTabListener（本））；
}
/**
*滑动viewpager时，选择相应的选项卡
* */
viewPager.setOnPageChangeListener（新的viewPager.OnPageChangeListener（）{
@凌驾
已选择页面上的公共无效（内部位置）{
//关于更改页面
//选择“受尊重”选项卡
actionBar.setSelectedNavigationItem（位置）；
}
@凌驾
已滚动页面上的公共void（int arg0、float arg1、int arg2）{
}
@凌驾
公共无效onPageScrollStateChanged（int arg0）{
}
});
}
@凌驾
已重新选择公共无效页签（页签，碎片事务）{
}
@凌驾
已选择的公共事务（选项卡，碎片事务ft）{
//在选定的选项卡上
//显示受尊重的片段视图
setCurrentItem（tab.getPosition（））；
}
@凌驾
已选择公共空页（选项卡，碎片事务ft）{
}
@凌驾
公共布尔onCreateOptions菜单（菜单）{
MenuInflater充气机=getMenuInflater（）；
充气机。充气（右菜单。主菜单，菜单）；
返回
Button button = (Button) findViewById(R.id.button_identity);