I need to create a simple array of some images. So that later on I can traverse through the array easily using a loop and access all the images one by one.
Just tell me the declaration part of storing the images into an array.
I will be having 5 images named as 1.png to 5.png which I need to access.
Will it be a string array or integer array ?
Array of ImageIcon:
ImageIcon[] images = new ImageIcon[5];
images[0] = new ImageIcon("path/to/image");
....
Your question is confusing. You clearly know what an array is and how to use it, but you don't know what type to use? Why, whichever type you want to use, of course. You could use String, or whatever class you usually use to represent an image.
Related
I'm trying filter my Mapbox layer (mapboxgl) to return just places that start with say 'North', 'South, 'East' or 'West'.
My places are in geojson data as a property.
I'm using map.setFilter with an expression to filter the geojson.
Example:
map.setFilter('markers', ["all",filter1,filter2]);
Where filter2 is a simple check on if the place is 'open' or 'closed' and filter1 is my main filter expression explained below.
The main issue is that the name of the place needs to START with one of these values.
So far I can do this IF the strings to check are all the same length by grabbing the length of the strings and then filtering by that substring of the name.
But this doesn't work (obviously) when I have words that are not the same length.
This is pretty simple in most other languages, but my brain cant figure out this in mapbox's expression filters for some reason!
Here's what I have so far (please excuse the poor code quality here, I'm not a professional coder!!):
//the array data to check for a match
filterArray = ['North','South','East','West'];
//checks first values length - not ideal!
var lengthToCheck = filterArray[0].length;
//apply it to the filter to only return ones starting with X
filter1 = ['in', ['slice',['to-string', ['get', 'name']],0,lengthToCheck], ['literal', filterArray]];
I have to slice the name of the place as it might be for example 'Northampton', which wont be found within the array value[0] being 'North'.
This is equally as bad code for the 'East' values as the name slice is going to be 5 characters, so it will be trying something like 'Eastb' (Eastbourne) within the array value 'East' which just wont work.
It would be good if I could some how flip this round so the filter can check the values in the array within the Name, but I can't figure this out!
Is there a way to do that or is there a magic expression feature I'm missing that would solve this problem?
I'm also going to have the same problem with a 'Contains' type check of an array of values too, but I'll cross that bridge once I figure this part out!
Any help appreciated (before I go putting in some convoluted workaround!).
If you have a statically allocated array, the Visual Studio debugger can easily display all of the array elements. However, if you have an array allocated dynamically and pointed to by a pointer, it will only display the first element of the array when you click the + to expand it. Is there an easy way to tell the debugger, show me this data as an array of type Foo and size X?
Yes, simple.
say you have
char *a = new char[10];
writing in the debugger:
a,10
would show you the content as if it were an array.
There are two methods to view data in an array m4x4:
float m4x4[16]={
1.f,0.f,0.f,0.f,
0.f,2.f,0.f,0.f,
0.f,0.f,3.f,0.f,
0.f,0.f,0.f,4.f
};
One way is with a Watch window (Debug/Windows/Watch). Add watch =
m4x4,16
This displays data in a list:
Another way is with a Memory window (Debug/Windows/Memory). Specify a memory start address =
m4x4
This displays data in a table, which is better for two and three dimensional matrices:
Right-click on the Memory window to determine how the binary data is visualized. Choices are limited to integers, floats and some text encodings.
In a watch window, add a comma after the name of the array, and the amount of items you want to be displayed.
a revisit:
let's assume you have a below pointer:
double ** a; // assume 5*10
then you can write below in Visual Studio debug watch:
(double(*)[10]) a[0],5
which will cast it into an array like below, and you can view all contents in one go.
double[5][10] a;
For,
int **a; //row x col
add this to watch
(int(**)[col])a,row
Yet another way to do this is specified here in MSDN.
In short, you can display a character array as several types of string. If you've got an array declared as:
char *a = new char[10];
You could print it as a unicode string in the watch window with the following:
a,su
See the tables on the MSDN page for all of the different conversions possible since there are quite a few. Many different string variants, variants to print individual items in the array, etc.
You can find a list of many things you can do with variables in the watch window in this gem in the docs:
https://msdn.microsoft.com/en-us/library/75w45ekt.aspx
For a variable a, there are the things already mentioned in other answers like
a,10
a,su
but there's a whole lot of other specifiers for format and size, like:
a,en (shows an enum value by name instead of the number)
a,mb (to show 1 line of 'memory' view right there in the watch window)
For MFC arrays (CArray, CStringArray, ...)
following the next link in its Tip #4
http://www.codeproject.com/Articles/469416/10-More-Visual-Studio-Debugging-Tips-for-Native-De
For example for "CArray pArray", add in the Watch windows
pArray.m_pData,5
to see the first 5 elements .
If pArray is a two dimensional CArray you can look at any of the elements of the second dimension using the next syntax:
pArray.m_pData[x].m_pData,y
I haven't found a way to use this with a multidimensional array. But you can at least (if you know the index of your desired entry) add a watch to a specific value. Simply use the index-operator.
For an Array named current, which has an Array named Attribs inside, which has an Array named Attrib inside, it should look like this if you like to have to position 26:
((*((*current).Attribs)).Attrib)[26]
You can also use an offset
((*((*current).Attribs)).Attrib)+25
will show ne "next" 25 elements.
(I'm using VS2008, this shows only 25 elements maximum).
I used to have a series of independent arrays (e.g. name(), id(), description() ). I used to be able to check whether a value existed in a specific array by doing name.include?("Mark")
Now that I moved to a MUCH MORE elegant way to manage different these independent arrays (here for background: How do I convert an Array with a JSON string into a JSON object (ruby)) I am trying to figure out how I do the same.
In short I put all the independent arrays in a single structure so that I can reference the content as object().name, object().id, object().description.
However I am missing now how I can check whether the object array has a value "Mark" in its name structure.
I have tried object.name.include?("Mark") but it doesn't quite like it.
I have also tried to use has_value?but that doesn't seem to be working either (likely because it used to be an hash before I imported it into the structure but right now is no longer a hash - see here: How do I convert an Array with a JSON string into a JSON object (ruby))
Thoughts? How can I check whether object.name contains a certain string?
Thanks.
If you want to find all customers called Mark you can write the following:
customers_named_mark = array_of_customers.select{|c| c.name == 'Mark' }
This will return a potentially empty array.
If you want to find the first customer named Mark, write
customer_named_mark = array_of_customers.detect{|c| c.name == 'Mark' }
This will return the first matching item or nil.
I need to retrieve 25 images from resources and put them into 25 picturebox randomly without any repetition happening. The process should be done automatically when the page loaded from the very beginning. I had named the picture as 1-25 and i suppose this could help the process.
Do we have any way to complete this process. Sorry for my poor language expression. Please help me, thanks.
One way (could be not the best in performance):
You need to generate the random numbers and store it in a list.
If the generated number is already present in the list, you get another one... at the end... you will have all the numbers
This one is better:
Dim rand As New Random()
Dim new_list As New List(Of Image)
Do While Pictures.Count > 0
' Move a random Image to the new list.
Dim i As Integer = rand.Next(0, Pictures.Count)
new_list.Add(Pictures(i))
Pictures.RemoveAt(i)
Loop
"Pictures" is a collection of images.
This code was taken from here: http://www.vb-helper.com/howto_net_random_picture_forms.html
I'm using Jammit to package assets up for a Rails application and I have a few asset files that I'd like to be included in each of a few groups. For example, I'd like Sammy and its plugins to be in both my mobile and screen JS packages.
I've tried this:
sammy: &SAMMY
- public/javascripts/vendor/sammy.js
- public/javascripts/vendor/sammy*.js
mobile:
<<: *SAMMY
- public/javascripts/something_else.js
and this:
mobile:
- *SAMMY
but both put the Sammy JS files in a nested Array, which Jammit can't understand. Is there a syntax for including the elements of an Array directly in another Array?
NB: I realize that in this case there are only two elements in the SAMMY Array, so it wouldn't be too bad to give each an alias and reference both in each package. That's fine for this case, but quickly gets unmaintainable when there are five or ten elements that have a specific load order.
Closest solution I know of is this one:
sammy:
- &SAMMY1
public/javascripts/vendor/sammy.js
- &SAMMY2
public/javascripts/vendor/sammy*.js
mobile:
- *SAMMY1
- *SAMMY2
- public/javascripts/something_else.js
Alternatively, as already suggested, flatten the nested lists in a code snippet.
Note: according to yaml-online-parser, your first suggestion is not a valid use of << (used to merge keys from two dictionaries. The anchor then has to point to another dictionary I believe.
If you want mobile to be equal to sammy, you can just do:
mobile: *SAMMY
However if you want mobile to contain other elements in addition to those in sammy, there's no way to do that in YAML to the best of my knowledge.
Your example is valid YAML (a convenient place to check is YPaste), but it's not defined what the merge does. Per the spec, a merge key can have a value:
A mapping, in which case it's merged into the parent mapping.
A sequence of mappings, in which case each is merged, one-by-one, into the parent mapping.
There's no way of merging sequences on YAML level.
You can, however, do this in code. Using the YAML from your second idea:
mobile:
- *SAMMY
you'll get nested sequences - so flatten them! Assuming you have a mapping of such nested sequences:
data = YAML::load(File.open('test.yaml'))
data.each_pair { |key, value| value.flatten! }
(Of course, if you have a more complicated YAML file, and you don't want every sequence flattened (or they're not all sequences), you'll have to do some filtering.)
This solution is for Symfony/PHP only (considerations for other languages, see below)
Note about array keys from the PHP array manual page:
Strings containing valid decimal ints, unless the number is preceded by a + sign, will be cast to the int type. E.g. the key "8" will actually be stored under 8. [...]
This means that if you actually index your anchor array with integer keys, you can simply add new keys by continuing the initial list. So your solution would look like this:
sammy: &SAMMY
1: public/javascripts/vendor/sammy.js
2: public/javascripts/vendor/sammy*.js
mobile:
<<: *SAMMY
3: public/javascripts/something_else.js
You can even overwrite keys and still add new ones:
laptop:
<<: *SAMMY
1: public/javascripts/sammy_laptop.js
3: public/javascripts/something_else.js
In both cases the end result is a perfectly valid indexed array, just like before.
Other programming languages
Depending on your YAML implementation and how you iterate over your array, this could conceivably also be used in other programming languages. Though with a caveat.
For instance, in JS you can access numerical string keys by their integer value as well:
const sammy = {"1": "public/javascripts/vendor/sammy.js"}
sammy["1"]; // "public/javascripts/vendor/sammy.js"
sammy[1]; // "public/javascripts/vendor/sammy.js"
But you'd need to keep in mind, that your initial array is now an object, and that you would need to iterate over it accordingly, e.g.:
Object.keys(sammy).forEach(key => console.log(sammy[key]))
As it has been suggested, when you need to flatten a list, at least in ruby, it is trivial to add a "!flatten" type specifier to mobile and implement a class that extends Array, adds the yaml_tag and flattens the coder seq on init_with.