如何在活动之间传递二维整数数组？

Question

I am trying to pass a 2d array of ints to nextactivity. i tried to use bundle.putSerializable(like sending a string array) but i got null pointer exception. Any ideas??

here is my code. (tosend)

Intent myIntent=new Intent(context,activityvogel.class);
                    Bundle mBundle = new Bundle();
                    mBundle.putSerializable("cost",cost);
                    myIntent.putExtras(mBundle);
                    startActivity(myIntent);}

(toreceive)

Bundle extras = getIntent().getExtras();
        final int cost[][]= (int[][]) extras.getSerializable("cost");

Answer 1

Convert int 2D array to String 2D array and send it just like you did

To convert: you would have to do so manually with a two-layer for() loop:

String[][] converted = new String[cost.length][];
for(int index = 0; index < cost.length; index++) {
    converted[index] = new String[cost[index].length];
    for(int subIndex = 0; subIndex < cost[index].length; subIndex++){
        converted[index][subIndex] = Integer.toString(cost[index][subIndex]);
    }
}

To send:

mBundle .putSerializable("cost", converted);

To get:

String[][] converted = (String[][]) mBundle.getSerializable("cost");

And then again convert it into int 2D array.

String[][] extends Object, while int and int[][] do not

Answer 2

Hope this work for get data:

String[][] strCost = null;
Object[] objCost = (Object[]) getIntent().getExtras().getSerializable("cost");
if (objCost != null){
    strCost = new String[objCost.length][];
    for(int i = 0; i < objCost.length; i++){
        strCost[i] = (String[]) objCost[i];
    }
}

Then turn back into int ...