我正在尝试构建引擎监视器，我通过蓝牙从arduino接收一串数据。我创建了bluetoothIn处理程序，它读取并将字符串拆分为变量。我需要将变量从字符串转换为整数或双精度，但在处理程序内执行此操作会导致应用程序崩溃。我知道处理程序返回这就是应用程序崩溃的原因。那么如何从处理程序中提取数据？
bluetoothIn = new Handler() {
public void handleMessage(android.os.Message msg) {
if (msg.what == handlerState) { //if message is what we want
String readMessage = (String) msg.obj; // msg.arg1 = bytes from connect thread
recDataString.append(readMessage); //keep appending to string until ~
int endOfLineIndex = recDataString.indexOf("~"); // determine the end-of-line
if (endOfLineIndex > 0) { // make sure there data before ~
String dataInPrint = recDataString.substring(0, endOfLineIndex); // extract string
txtString.setText("Data Received = " + dataInPrint);
int dataLength = dataInPrint.length();
txtStringLength.setText("String Length = " + String.valueOf(dataLength));
if (recDataString.charAt(0) == '#') {
//datapro=String.valueOf(recDataString);
//Message msg = Message.obtain();
//msg.obj=datapro;
//msg.setTarget(Handler2);
//msg.sendToTarget();
sensor0 = recDataString.substring(1, 5); //get sensor value from string between indices 1-5
sensor1 = recDataString.substring(6, 10);
sensor2 = recDataString.substring(11, 15);
sensor3 = recDataString.substring(16, 20);
RPM = (Double.valueOf(sensor2) * 1000);
V = ((RPM / ratio[box]) / FD) * (0.118);
status = Integer.valueOf(sensor3);
sensorView0.setText(" Battery Voltage = " + sensor0 + "V"); //update the textviews with sensor values
sensorView1.setText(" Velocity = " + String.valueOf(V));
sensorView2.setText("RPM=" + String.valueOf(RPM));
sensorView3.setText(String.valueOf(status));
}
recDataString.delete(0, recDataString.length()); //clear all string data
// strIncom =" ";
dataInPrint = " ";
}
}
}
};
logcat的：
04-26 17:07:51.288: I/art(13924): Late-enabling -Xcheck:jni
04-26 17:07:51.413: D/BluetoothAdapter(13924): 72305841: getState() : mService = null. Returning STATE_OFF
04-26 17:07:51.426: D/OpenGLRenderer(13924): Use EGL_SWAP_BEHAVIOR_PRESERVED: true
04-26 17:07:51.435: D/Atlas(13924): Validating map...
04-26 17:07:51.500: I/Adreno-EGL(13924): <qeglDrvAPI_eglInitialize:379>: QUALCOMM Build: 01/15/15, ab0075f, Id3510ff6dc
04-26 17:07:51.501: I/OpenGLRenderer(13924): Initialized EGL, version 1.4
04-26 17:07:51.521: D/OpenGLRenderer(13924): Enabling debug mode 0
04-26 17:08:45.253: W/BluetoothAdapter(15820): getBluetoothService() called with no BluetoothManagerCallback
04-26 17:08:51.273: D/AndroidRuntime(15820): Shutting down VM
04-26 17:08:51.273: D/AndroidRuntime(15820): --------- beginning of crash
04-26 17:08:51.275: E/AndroidRuntime(15820): FATAL EXCEPTION: main
04-26 17:08:51.275: E/AndroidRuntime(15820): Process: com.example.alpha_version, PID: 15820
04-26 17:08:51.275: E/AndroidRuntime(15820): java.lang.NumberFormatException: Invalid int: "0.00"
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.Integer.invalidInt(Integer.java:138)
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.Integer.parse(Integer.java:410)
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.Integer.parseInt(Integer.java:367)
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.Integer.parseInt(Integer.java:334)
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.Integer.valueOf(Integer.java:525)
04-26 17:08:51.275: E/AndroidRuntime(15820): at com.example.alpha_version.Main$1.handleMessage(Main.java:95)
04-26 17:08:51.275: E/AndroidRuntime(15820): at android.os.Handler.dispatchMessage(Handler.java:102)
04-26 17:08:51.275: E/AndroidRuntime(15820): at android.os.Looper.loop(Looper.java:135)
04-26 17:08:51.275: E/AndroidRuntime(15820): at android.app.ActivityThread.main(ActivityThread.java:5254)
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.reflect.Method.invoke(Native Method)
04-26 17:08:51.275: E/AndroidRuntime(15820): at java.lang.reflect.Method.invoke(Method.java:372)
04-26 17:08:51.275: E/AndroidRuntime(15820): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
04-26 17:08:51.275: E/AndroidRuntime(15820): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
04-26 17:08:57.542: I/Process(15820): Sending signal. PID: 15820 SIG: 9
04-26 17:08:57.942: D/OpenGLRenderer(15987): Use EGL_SWAP_BEHAVIOR_PRESERVED: true
04-26 17:08:57.948: D/Atlas(15987): Validating map...
04-26 17:08:58.010: I/Adreno-EGL(15987): <qeglDrvAPI_eglInitialize:379>: QUALCOMM Build: 01/15/15, ab0075f, Id3510ff6dc
04-26 17:08:58.012: I/OpenGLRenderer(15987): Initialized EGL, version 1.4
04-26 17:08:58.066: D/OpenGLRenderer(15987): Enabling debug mode 0
答案 0 :(得分：0)
您的c我想这是您status = Integer.valueOf(sensor3);中的第95行。此语句抛出异常，因为Main.java的值为sensor3，显然不是int
答案 1 :(得分：0)
status = Integer.valueOf(sensor3);
我还删除了一些您不需要的String.valueOf。
bluetoothIn = new Handler() {
public void handleMessage(android.os.Message msg) {
if (msg.what == handlerState) { //if message is what we want
String readMessage = (String) msg.obj; // msg.arg1 = bytes from connect thread
recDataString.append(readMessage); //keep appending to string until ~
int endOfLineIndex = recDataString.indexOf("~"); // determine the end-of-line
if (endOfLineIndex > 0) { // make sure there data before ~
String dataInPrint = recDataString.substring(0, endOfLineIndex); // extract string
txtString.setText("Data Received = " + dataInPrint);
int dataLength = dataInPrint.length();
txtStringLength.setText("String Length = " + String.valueOf(dataLength)); // <-- removed String.valueOf
if (recDataString.charAt(0) == '#') {
//datapro=String.valueOf(recDataString);
//Message msg = Message.obtain();
//msg.obj=datapro;
//msg.setTarget(Handler2);
//msg.sendToTarget();
sensor0 = recDataString.substring(1, 5); //get sensor value from string between indices 1-5
sensor1 = recDataString.substring(6, 10);
sensor2 = recDataString.substring(11, 15);
sensor3 = recDataString.substring(16, 20);
RPM = (Double.valueOf(sensor2) * 1000);
V = ((RPM / ratio[box]) / FD) * (0.118);
// status = Integer.valueOf(sensor3); // <-- you do not need this
sensorView0.setText(" Battery Voltage = " + sensor0 + "V"); //update the textviews with sensor values
sensorView1.setText(" Velocity = " + V); // <-- removed String.valueOf
sensorView2.setText("RPM=" + RPM); // <-- removed String.valueOf
sensorView3.setText("Status " + status); // <-- removed String.valueOf
}
recDataString.delete(0, recDataString.length()); //clear all string data
// strIncom =" ";
dataInPrint = " ";
}
}
}
};