我根本没有找到在活动之间共享实时数据的解决方案。我的第一个活动接收实时对象（双精度型，随机数）。我想把这个数字传递给第二个活动。一切正常，只有第二个 Activity 只显示一次数据。我必须通过返回第一个活动来刷新活动，然后第二个活动才会显示最新数据。我实现了一个单格顿模式：
public class FirstActivity extends Activity{
public double xAxis;
public double yAxis;
public static FirstView instance;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.device_view);
handler = new Handler() {
@Override
public void handleMessage(Message msg) {
int data1 = msg.arg1;
xAxis = (double) data1;
dataX.setText(String.valueOf(xAxis));
int data2 = msg.arg2;
yAxis = (double) data2;
dataY.setText(String.valueOf(yAxis));
}
};
secondview.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent nextScreen = new Intent(getApplicationContext(),
SecondActivity.class);
startActivity(nextScreen);
}
});
}
public static void initInstance(){
if(instance == null)
{
instance = new FirstActivity();
}
}
public static FirstActivity getInstance(){
return instance;
}
}
第二视图类
public class SecondActivity extends Activity{
private double valueX;
private double valueY;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.linegraph);
valueX = FirstActivity.getInstance().xAxis;
valueY = FirstActivity.getInstance().yAxis;
}
}
应用类
package com.bluetoothcomm;
import android.app.Application;
public class MyApplication extends Application {
@Override
public void onCreate(){
super.onCreate();
initSingeltons();
}
public void initSingeltons(){
FirstActivity.initInstance();
}
}