在活动之间传递“偏好变量”，在原始活动中设置值
问题描述：
我试图让用户以文本形式输入其模块的蓝牙地址。在活动之间传递“偏好变量”，在原始活动中设置值
按菜单在活动1（MainActivity.java）调出一个选项菜单。选择设置切换到活动2（SetPreferences.java）。在文本框中输入MAC地址并按应用恢复活动1，地址值不变。
任何帮助将不胜感激的家伙！
开始代码：
MainActivity.java：
package com.showstopperled.defiance;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.util.Random;
import java.util.UUID;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.content.SharedPreferences;
import android.graphics.Color;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import com.showstopperled.defiance.ColorPickerDialog.OnColorChangedListener;
public class MainActivity extends Activity implements OnColorChangedListener {
public static final String PREFS_NAME = "DefiancePrefsFile";
static String Packet = null;
private BluetoothAdapter mBluetoothAdapter = null;
private BluetoothSocket btSocket = null;
private static OutputStream outStream = null;
SeekBar seekbarUnicorns, seekbarChan, seekbarRed, seekbarGreen,
seekbarBlue, seekbarBand, seekbarSens;
TextView valueUnicorns, valueChan, valueRed, valueGreen, valueBlue,
valueBand, valueSens, valueSave;
static int Channel = 0;
static int Rset = 255;
static int Gset = 0;
static int Bset = 0;
static int Mode = 0;
static int Band = 0;
static int Sens = 24;
static int Save = 0;
static int Unicorns = 0;
String audB = "63Hz";
private static final UUID MY_UUID = UUID
.fromString("00001101-0000-1000-8000-00805F9B34FB");
// hardcoded MAC address
static String address = null;
private BufferedReader buf;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
valueChan = (TextView) findViewById(R.id.textViewChan);
seekbarChan = (SeekBar) findViewById(R.id.seekBarChan);
valueRed = (TextView) findViewById(R.id.textViewRed);
seekbarRed = (SeekBar) findViewById(R.id.seekBarRed);
valueGreen = (TextView) findViewById(R.id.textViewGreen);
seekbarGreen = (SeekBar) findViewById(R.id.seekBarGreen);
valueBlue = (TextView) findViewById(R.id.textViewBlue);
seekbarBlue = (SeekBar) findViewById(R.id.seekBarBlue);
valueBand = (TextView) findViewById(R.id.textViewBand);
seekbarBand = (SeekBar) findViewById(R.id.seekBarBand);
valueSens = (TextView) findViewById(R.id.textViewSens);
seekbarSens = (SeekBar) findViewById(R.id.seekBarSens);
valueUnicorns = (TextView) findViewById(R.id.textViewUnicorns);
seekbarUnicorns = (SeekBar) findViewById(R.id.seekBarUnicorns);
Spinner s = (Spinner) findViewById(R.id.spinnerMode);
s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
public void onItemSelected(AdapterView<?> adapter, View v, int i,
long lng) {
Mode = i;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onNothingSelected(AdapterView<?> arg0) {
// do something else
}
});
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
Toast.makeText(this, "Bluetooth is not available.",
Toast.LENGTH_LONG).show();
finish();
return;
}
if (!mBluetoothAdapter.isEnabled()) {
Toast.makeText(this,
"Please enable your BT and re-run this program.",
Toast.LENGTH_LONG).show();
finish();
return;
}
int sbar_chan_position = settings.getInt("seekbar_chan_pref", 0);
seekbarChan.setProgress(sbar_chan_position);
valueChan.setText("Channel: " + sbar_chan_position);
Channel = sbar_chan_position;
int sbar_red_position = settings.getInt("seekbar_red_pref", 0);
seekbarRed.setProgress(sbar_red_position);
valueRed.setText("Red: " + sbar_red_position);
Rset = sbar_red_position;
int sbar_green_position = settings.getInt("seekbar_green_pref", 0);
seekbarGreen.setProgress(sbar_green_position);
valueGreen.setText("Green: " + sbar_green_position);
Gset = sbar_green_position;
int sbar_blue_position = settings.getInt("seekbar_blue_pref", 0);
seekbarBlue.setProgress(sbar_blue_position);
valueBlue.setText("Blue: " + sbar_blue_position);
Bset = sbar_blue_position;
int sbar_band_position = settings.getInt("seekbar_band_pref", 0);
seekbarBand.setProgress(sbar_band_position);
valueBand.setText("Band: " + sbar_band_position);
Band = sbar_band_position;
int sbar_sens_position = settings.getInt("seekbar_sens_pref", 0);
seekbarSens.setProgress(sbar_sens_position);
valueSens.setText("Sensitivity: " + sbar_sens_position);
Sens = sbar_sens_position;
int sbar_unicorns_position = settings
.getInt("seekbar_unicorns_pref", 0);
seekbarUnicorns.setProgress(sbar_unicorns_position);
valueUnicorns.setText("Unicorns!: " + sbar_unicorns_position);
Unicorns = sbar_unicorns_position;
seekbarChan.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
valueChan.setText("Channel: " + (progress + 1));
Channel = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
seekbarRed.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
valueRed.setText("Red: " + progress);
Rset = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
seekbarGreen.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
valueGreen.setText("Green: " + progress);
Gset = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
seekbarBlue.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
valueBlue.setText("Blue: " + progress);
Bset = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
seekbarBand.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
switch (progress) {
case 0:
audB = "63Hz";
break;
case 1:
audB = "160Hz";
break;
case 2:
audB = "400Hz";
break;
case 3:
audB = "1kHz";
break;
case 4:
audB = "2.5kHz";
break;
case 5:
audB = "6.25kHz";
break;
case 6:
audB = "16kHz";
break;
}
valueBand.setText("Band: " + audB);
Band = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
seekbarSens.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
valueSens.setText("Sensitivity: " + (progress + 1));
Sens = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns,
Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
seekbarUnicorns
.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
public void onProgressChanged(SeekBar seekBar,
int progress, boolean fromUser) {
valueUnicorns.setText("Unicorns!: " + progress);
Unicorns = progress;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens,
Unicorns, Save);
}
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});
}
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
menu.add(0, 0, 0, "Settings");
menu.add(0, 1, 0, "About");
menu.add(0, 2, 0, "Help");
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
super.onOptionsItemSelected(item);
switch (item.getItemId()) {
case 0:
Intent intent = new Intent();
intent.setClass(MainActivity.this, SetPreferences.class);
startActivityForResult(intent, 0);
address = intent.getExtras().getString("address");
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putString("address", address);
editor.commit();
return true;
case 1:
// launch ABOUT here
break;
case 2:
// Launch here
break;
default:
// Launch SETTINGS here
break;
}
return false;
}
public boolean onPrepareOptionsMenu(Menu menu) {
return super.onPrepareOptionsMenu(menu);
}
public void colorChanged(int color) {
int sbar_red_position = Color.red(color);
int sbar_green_position = Color.green(color);
int sbar_blue_position = Color.blue(color);
seekbarRed.setProgress(sbar_red_position);
valueRed.setText("Red: " + sbar_red_position);
Rset = sbar_red_position;
seekbarGreen.setProgress(sbar_green_position);
valueGreen.setText("Green: " + sbar_green_position);
Gset = sbar_green_position;
seekbarBlue.setProgress(sbar_blue_position);
valueBlue.setText("Blue: " + sbar_blue_position);
Bset = sbar_blue_position;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
}
@Override
public void onStart() {
super.onStart();
}
@Override
public void onResume() {
super.onResume();
try {
File f = new File(Environment.getExternalStorageDirectory()
+ "/Defiance.txt");
FileInputStream fileIS = new FileInputStream(f);
buf = new BufferedReader(new InputStreamReader(fileIS));
String readString = new String();
// just reading each line and pass it on the debugger
while ((readString = buf.readLine()) != null) {
address = readString;
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
// When this returns, it will 'know' about the server,
// via it's MAC address.
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
try {
btSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
}
mBluetoothAdapter.cancelDiscovery();
try {
btSocket.connect();
} catch (IOException e) {
try {
btSocket.close();
} catch (IOException e2) {
}
}
// Create a data stream so we can talk to server.
try {
outStream = btSocket.getOutputStream();
} catch (IOException e) {
}
}
public void onClickSave1(View v) throws IOException {
Save = 100;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickSave2(View v) throws IOException {
Save = 200;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickSave3(View v) throws IOException {
Save = 300;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickSave4(View v) throws IOException {
Save = 400;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickSave5(View v) throws IOException {
Save = 500;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickLoad1(View v) throws IOException {
Save = 10;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickLoad2(View v) throws IOException {
Save = 20;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickLoad3(View v) throws IOException {
Save = 30;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickLoad4(View v) throws IOException {
Save = 40;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickLoad5(View v) throws IOException {
Save = 50;
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
Save = 0;
}
public void onClickApply(View v) throws IOException {
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
}
@Override
public void onPause() {
super.onPause();
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putInt("seekbar_red_pref", Rset);
editor.putInt("seekbar_green_pref", Gset);
editor.putInt("seekbar_blue_pref", Bset);
editor.putString("address", address);
editor.commit();
if (outStream != null) {
try {
outStream.flush();
} catch (IOException e) {
}
}
try {
btSocket.close();
} catch (IOException e2) {
}
}
@Override
public void onStop() {
super.onStop();
}
@Override
public void onDestroy() {
super.onDestroy();
// Stop the Bluetooth chat services
}
public void onClickColorPicker(View v) {
new ColorPickerDialog(this, this, Color.rgb(Rset, Gset, Bset)).show();
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
}
public void onClickRandomColor(View v) {
Random rnd = new Random();
int min = 0, max = 255;
int randomRed = rnd.nextInt(max - min + 1) + min;
int randomGreen = rnd.nextInt(max - min + 1) + min;
int randomBlue = rnd.nextInt(max - min + 1) + min;
Rset = randomRed;
Gset = randomGreen;
Bset = randomBlue;
new ColorPickerDialog(this, this, Color.rgb(Rset, Gset, Bset)).show();
packet(Channel, Rset, Gset, Bset, Mode, Band, Sens, Unicorns, Save);
}
public static void packet(int Channel, int Rset, int Gset, int Bset,
int Mode, int Band, int Sens, int Unicorns, int Save) {
int Rfin;
int Gfin;
int Bfin;
int Sfin;
int Ufin;
Rfin = Rset * 16;
Rfin = 4095 - Rfin;
Gfin = Gset * 16;
Gfin = 4095 - Gfin;
Bfin = Bset * 16;
Bfin = 4095 - Bfin;
Sfin = Sens * 32;
Ufin = Unicorns * 10;
Ufin = 1000 - Ufin;
Packet = "<HMG:" + Channel + ":" + Rfin + ":" + Gfin + ":" + Bfin + ":"
+ Mode + ":" + Band + ":" + Sfin + ":" + Ufin + ":" + Save
+ ">";
byte[] msgBuffer;
msgBuffer = Packet.getBytes();
try {
outStream.write(msgBuffer);
} catch (IOException e) {
}
}
}
SetPreferences.java：
package com.showstopperled.defiance;
import java.io.IOException;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class SetPreferences extends Activity {
EditText editMac;
TextView valueMac;
String address;
public static final String PREFS_NAME = "DefiancePrefsFile";
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.set_preferences);
EditText MacAddress = (EditText) findViewById(R.id.editMac);
MacAddress = (EditText) findViewById(R.id.editMac);
address = MacAddress.getText().toString();
valueMac = (TextView) findViewById(R.id.textViewMac);
}
public void onClickMac(View v) throws IOException {
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putString("address", address);
editor.commit();
address = settings.getString("address", address);
valueMac.setText("Mac Address: " + address);
Intent i = new Intent(this, MainActivity.class);
i.putExtra("address", address);
startActivity(i);
}
}
答
看起来你正在做一个startActivityForResult，然后后得到的意图的价值。
这将无法正常工作，有以下原因：
startActivityForResult实际上不会触发，直到你调用它的方法（或者更具体地说，该事件在UI运行的线程的Looper ）返回。
要得到一个活动的结果，你应该使用onActivityResult。这个意图将会有你想要的价值。
你在做什么说的是活套开始在方法返回时，那么你得到一个额外的出你自己的意图，然后返回并让活动开始活动。当它返回时，你不检查它的结果。
更改 startActivityForResult（0，intent）;到 onActivityResult（0，1，intent）; 导致立即强制关闭，你想日志？ – dmattox10 2013-03-01 23:02:54
不，不，你正在派发结果就好了，这是接收中断。 覆盖您活动的onActivityResult方法。阅读我链接到的javadoc。 – 2013-03-02 07:41:01