如何将数据从 MainActivity 传递到多个活动

Question

My project looks something like this:

1. MainActivity
2. SelectActivity
3. MapActivity

I have data on my MainActivity that i need to send to MapActivity, the problem is that i can not go straight to MapActivity without have selected an item from my SelectActivity.

I was doing the following:

    Intent intent = new Intent(MainActivity.this, MapSelectActivity.class);
    Bundle b = new Bundle();
    b.putDouble("Lon",longitude);
    b.putDouble("Lat",latitude);
    intent.putExtras(b);
    startActivity(intent);

But the app just started crashing due to the thing i mention earlier that i can not go into the activity without have been selected something from the SelectActivity.

Anythought on how can I make this?. I hope i've made myself clear. Thank you in advace for your help.

Answer 1

As you navigate from MainActivity to SelectActivity and then from SelectActivity to MapActivity

And you want to send data from MainActivity to MapActivity , then you can send this data in two stages:

• Stage 1: from MainActivity to SelectActivity
• Stage 2: from SelectActivity to MapActivity

In MainActivity:

Intent intent = new Intent(MainActivity.this, SelectActivity.class);
Bundle b = new Bundle();
b.putDouble("Lon",longitude);
b.putDouble("Lat",latitude);
intent.putExtras(b);
startActivity(intent);

In SelectActivity:

// get the bundle sent from MainActivity to SelectActivity
Bundle b = getIntent().getExtras();
Intent intent = new Intent(SelectActivity.this, MapActivity.class);

// add more data to bundle from the SelectActivity
// b.addXX();

intent.putExtras(b);
startActivity(intent);

In MapActivity:

// get the bundle sent from SelectActivity to MapActivity
Bundle b = getIntent().getExtras();
b.getDouble("Lon");
b.getDouble("Lat");