How to get the size of the file array in android?

Question

I use this codes to get all Folders:

 File MyDir[] = getExternalCacheDirs();

And then I use these code to show the path:

Toast.makeText(getApplicationContext(), MyDir[0].getPath(), Toast.LENGTH_LONG).show();
Toast.makeText(getApplicationContext(), MyDir[1].getPath(), Toast.LENGTH_LONG).show();

However, I wonder how to get the length of the file list, so I can use the for-loop to show all path

Like:

for (j = 0; j <= <size_of_the_list>; j += 1) { 
 Toast.makeText(getApplicationContext(),MyDir[j].getPath(),Toast.LENGTH_LONG).show();
}

ΦXocę 웃 Пepeúpa ツ · Accepted Answer · 2015-11-25T09:49:38.527

1

MyDir is an array, why dont you do:

// MyDir.length


for (j = 0; j < MyDir.length; j ++) { 
    Toast.makeText(getApplicationContext(), MyDir[j].getPath(),       Toast.LENGTH_LONG).show();
}

?

edited Nov 25 '15 at 09:49

answered Nov 25 '15 at 09:35

ΦXocę 웃 Пepeúpa ツ

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but file array is same as others array? – Question-er XDD Nov 25 '15 at 09:40
["you can use the built-in length property to determine the size of **any** array"](https://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html) – Andy Turner Nov 25 '15 at 09:41
oh fixed, I added length() instead of length, haha thz – Question-er XDD Nov 25 '15 at 09:49

score 1 · Answer 2 · edited May 23 '17 at 12:24

1

You are searching for the length property

for (j=0; j< MyDir.length; j++) { 

}

Here is a more detail thread about it

edited May 23 '17 at 12:24

Community

1
1

answered Nov 25 '15 at 09:36

ThomasThiebaud

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score 1 · Answer 3 · answered Nov 25 '15 at 09:38

It here:

public static long folderSize(File directory) {
    long length = 0;
    for (File file : directory.listFiles()) {
        if (file.isFile())
            length += file.length();
        else
            length += folderSize(file);
    }
    return length;
}

score 1 · Answer 4 · answered Nov 25 '15 at 09:40

If you are unfamiliar with arrays, I would suggest that you check out the Arrays part of the nuts and bolts tutorial.

You are looking for the length property of the array:

for (j = 0; j < array.length; j += 1) { }

Note that you should be using < rather than <=, because there are array.length elements in the array, not array.length + 1. The last element of the array is array[array.length - 1] (assuming it is not empty).

score 1 · Answer 5 · answered Nov 25 '15 at 09:41

1

To answer your question, you can get the size of the array by calling .length on it.

array.length

You should also look at this to learn more about arrays. http://docs.oracle.com/javase/tutorial/java/nutsandbolts/arrays.html

answered Nov 25 '15 at 09:41

Shiladittya Chakraborty

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How to get the size of the file array in android?

5 Answers5