持续更新android Textview
我正在开发一个Android应用程序,它有一个持续更新android Textview,android,android-layout,textview,android-service,Android,Android Layout,Textview,Android Service,我正在开发一个Android应用程序,它有一个活动类和服务类。在服务中,每隔10毫秒将接收连续批量数据(1090字节)。我需要使用这些批量数据不断更新文本视图。从连续后台服务更新文本视图的推荐方法是什么 服务等级 public class RecepService extends Service { public static Handler mHandler; StringBuilder hexstring; @Override public IBinder onBind(Intent i
活动
类和服务
类。在服务中
,每隔10毫秒将接收连续批量数据(1090字节)
。我需要使用这些批量数据不断更新文本视图
。从连续后台服务更新文本视图
的推荐方法是什么
服务等级
public class RecepService extends Service {
public static Handler mHandler;
StringBuilder hexstring;
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
init();
}
private void init() {
mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (msg.what == 0x123) {
byte[] readBuf = (byte[]) msg.obj;
int readBuflen = msg.arg1;
// here will receive 1090 bytes of data
// every 10 milliseconds
Receivepatientattributes(readBuf,readBuflen);
}
}
};
}
public void Receivepatientattributes(byte[] readBuf, int len) {
String total_data = "";
total_data = bytetohex(readBuf, len);
MainActivity.recep.setText(MainActivity.recep.getText().toString() + "\t" +
"" + total_data );
}
String bytetohex(byte[] txt, int len) {
String p="";
byte[] text = new byte[len];
text = txt;
hexstring = new StringBuilder();
for (int j = 0; j < len; j++) {
String hex= Integer.toHexString(0xFF & txt[j]);
if (hex.length()==1) {
hexstring.append("0");
}
hexstring.append(hex+" ");
}
p=p+hexstring.toString();
return p;
}
@Override
public void onDestroy() {
super.onDestroy();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
}
公共类RecepService扩展服务{
公共静态处理器;
字符串生成器;
@凌驾
公共IBinder onBind(意向){
返回null;
}
@凌驾
public void onCreate(){
super.onCreate();
init();
}
私有void init(){
mHandler=新处理程序(){
@凌驾
公共无效handleMessage(消息消息消息){
如果(msg.what==0x123){
字节[]readBuf=(字节[])msg.obj;
int readBuflen=msg.arg1;
//这里将接收1090字节的数据
//每10毫秒
收到患者的礼物(readBuf、readBuflen);
}
}
};
}
公共无效接收患者属性(字节[]readBuf,整数){
字符串total_data=“”;
总数据=bytetohex(readBuf,len);
MainActivity.recep.setText(MainActivity.recep.getText().toString()+“\t”+
“”+总数据);
}
字符串bytetohex(字节[]txt,整数len){
字符串p=“”;
字节[]文本=新字节[len];
text=txt;
hexstring=新的StringBuilder();
对于(int j=0;j
您可以使用它不断更新您的文本视图
每次使用最新值运行服务时,在首选项中设置值
现在在计时器中,从首选项中获取该值,并用该值更新TextView
下面是一些代码:
class UpdateTimeTask extends TimerTask {
public void run() {
textview.setText("updated value");
}
}
在onCreate()中设置
用户本地广播管理器
public void Receivepatientattributes(byte[] readBuf, int len) {
String total_data = "";
total_data = bytetohex(readBuf, len);
Intent intent = new Intent("update-text");
// add data
intent.putExtra("message", total_data);
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
}
主要活动
@Override
public void onResume() {
super.onResume();
// Register mMessageReceiver to receive messages.
LocalBroadcastManager.getInstance(this).registerReceiver(mMessageReceiver,
new IntentFilter("update-text"));
}
private boolean mCanBeUpdated = true;
private static final int ONE_SEC = 1000; //ms
private static final int RECEPTION_SPEED = 10; //ms
private static final int CYCLES = (int) (ONE_SEC / RECEPTION_SPEED);
private int mCurrentCycle = -1;
private String mMsgCache = "";
// handler for received Intents for the "update-text" event
private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
// Extract data included in the Intent
String message = intent.getStringExtra("message");
Log.d("receiver", "Got message: " + message);
mMsgCache = mMsgCache + "\t" + message;
if (mCanBeUpdated) {
// No problem updating UI here, refer --> http://stackoverflow.com/a/5676888/1008278
final Handler handler = new Handler(context.getMainLooper());
handler.post(new Runnable() {
@Override
public void run() {
MainActivity.recep.append(mMsgCache);
mMsgCache = "";
}
});
mCanBeUpdated = false;
} else if (mCurrentCycle >= CYCLES) {
mCurrentCycle = -1;
mCanBeUpdated = true;
} else {
mCurrentCycle++;
}
}
};
@Override
protected void onPause() {
// Unregister since the activity is not visible
LocalBroadcastManager.getInstance(this).unregisterReceiver(mMessageReceiver);
super.onPause();
}
如果您想使用时间表和计时器任务,那么您可以 要解决当前问题,请遵循以下说明。 假设您的活动具有广播接收器
private BroadcastReceiver mReceiver;
然后覆盖将在哪里注册广播接收器的方法onResume()
,以及将在哪里取消注册接收器的方法onPause()
:
@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
IntentFilter intentFilter = new IntentFilter(
"android.intent.action.MAIN");
mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
//extract your message from intent
String msg_for_me = intent.getStringExtra("YOUR_MESSAGE");
//log your message value
Log.i("MyTag", msg_for_me);
}
};
//registering your receiver
this.registerReceiver(mReceiver, intentFilter);
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
//unregister your receiver
this.unregisterReceiver(this.mReceiver);
}
在这里,广播接收器通过android.intent.action.MAIN进行过滤,消息将使用此过滤器从服务中广播
现在,您的方法receivePatientatAttributes
将如下所示:
public void Receivepatientattributes(byte[] readBuf, int len) {
String total_data = "";
total_data = bytetohex(readBuf, len);
Intent i = new Intent("android.intent.action.MAIN").putExtra("YOUR_MESSAGE", total_data);
this.sendBroadcast(i);
}
就这样。:) 使用处理程序,因为处理程序允许从其他后台线程与UI线程通信
boolean handlerStop = false;
void handleHandler(){
Handler handler =new Handler();
final Runnable r = new Runnable() {
public void run() {
handler.postDelayed(this, 30000);
if(!handlerStop) {
updateTextView() //update your text with other thread like asyncronous thread
}
}
};
handler.postDelayed(r, 0000);
}
@Override
public void onResume() {
super.onResume();
handlerStop=false;
handleHandler();
}
@Override
public void onPause() {
super.onPause();
handlerStop=true;
handleHandler();
}
@Override
public void onStop() {
super.onStop();
handlerStop=true;
handleHandler();
}
但我的UI在一段时间后挂起,此时文本视图的更新值当然会被挂起。增加了您的持续时间。但我的UI在一段时间后挂起,而文本视图的更新值10毫秒太快。你应该考虑每隔1秒更新TeTVIEW。或者每次设置文本时,可以将新文本附加到现有文本。检查我的编辑。实际上数据接收部分来自ECG WIFI模块。所以我们不能减少时间。如果我减少丢失数据的时间。@Arya在(1000/10)个周期更新-->清除缓存和重做后,您可以在变量-->中本地缓存。阅读“绑定服务”模式
boolean handlerStop = false;
void handleHandler(){
Handler handler =new Handler();
final Runnable r = new Runnable() {
public void run() {
handler.postDelayed(this, 30000);
if(!handlerStop) {
updateTextView() //update your text with other thread like asyncronous thread
}
}
};
handler.postDelayed(r, 0000);
}
@Override
public void onResume() {
super.onResume();
handlerStop=false;
handleHandler();
}
@Override
public void onPause() {
super.onPause();
handlerStop=true;
handleHandler();
}
@Override
public void onStop() {
super.onStop();
handlerStop=true;
handleHandler();
}