完成任务后如何显示Toast？

Question

I use this code to delete a file

File dir = new File(Environment.getExternalStorageDirectory() + "/myapp/" + "/Media/");
if (dir.isDirectory()) {
    String[] children = dir.list();
    for (int i = 0; i < children.length; i++) {
        new File(dir, children[i]).delete();

    }

    Toast.makeText(appActivity.this, "done", Toast.LENGTH_SHORT).show();

}

I want to show Toast "done" after deleting the file from folder and other Toast "No file" if there is o file in the folder.

How can I do that?

Answer 1

What you need is an if else statement, for more help on if else statements read the Android Developers documentation https://developer.android.com/reference/java/util/concurrent/locks/Condition.html

Try this;

  File dir = new File(Environment.getExternalStorageDirectory() + "/myapp/" + "/Media/");
if (dir.isDirectory()) {
String[] children = dir.list();
for (int i = 0; i < children.length; i++) {
    new File(dir, children[i]).delete();

}

Toast.makeText(appActivity.this, "done", Toast.LENGTH_SHORT).show();

else {
Toast.makeText(appActivity.this, "no file!", Toast.LENGTH_SHORT).show();
}

}

Answer 2

well i think this should work

File dir = new File(Environment.getExternalStorageDirectory() + "/myapp/" + "/Media/");
if (dir.isDirectory()) {
    String[] children = dir.list();
//if there are files to delete inside the folder
    if(children.length>0){
        Toast.makeText(appActivity.this, "done", Toast.LENGTH_SHORT).show();
    }
//if there are no files inside the folder
    else{
        Toast.makeText(appActivity.this, "No files to delete", Toast.LENGTH_SHORT).show(); 
    }
    for (int i = 0; i < children.length; i++) {
        new File(dir, children[i]).delete();

    }



}
else{
    Toast.makeText(appActivity.this, "No Such directory exists", Toast.LENGTH_SHORT).show();
}

Hope this helps