Trees are generally used for managing data but which particular type of trees are used?
A typical memory representation of a file directory tree looks something like this:
class Directory
string Name
List<Directory> Directories
List<string> Files
Briefly, a Directory contains two types of child nodes: files and directories. You can represent the files as strings, or if you want more information you can create a File class of some kind. A Directory, of course, is a recursive data structure.
To traverse the thing, you write something like this:
TraverseDirectory(Directory d)
output d.Name
for each file in d.Files
output file // it's a string
for each Directory subdir in d.Directories
TraverseDirectory(subdir)
Convert to your favorite language, modify as desired.
Related
I have some image files which will be dynamically loaded in my app. I know I can put images in the "/res/drawable" directory, but can there be somewhere else I can put files and loaded them by file name at runtime?
The image files contain characters that are now allowed in resource names. I did not name them, so ideally, I need to keep the names. For example, suppose I have "Cat #1.png" and "Cat #2.png", and I would like to load the image into an ImageView by that name at runtime, like so:
MyImageView1.setImageBitmap(createBitmapFromContentDirectory("Cat Pictures/Cat #2.png"))
MyImageView2.setImageBitmap(createBitmapFromContentDirectory("Dog Pictures/Dog #1.png"))
Is that possible, or should I change all image names into conforming names (e.g., cat_number1.png and cat_number2.png) and put them into the drawable directory?
You can put them in assets & load them from there,
Otherwise you can also put them in raw folder.
you can refer to Where do I I Place assets folder for assets.assets doesn't create Resource Id, so you can access them directly. Have a look at this
difference between assets & raw.
I am using Assets files as help files in my app and have well over a dozen. I am porting the app to multiple languages. Where do the alternative language asset files go?
I am already using the "res/values" directories for language files (values, values-es, etc) for use within the app. I thought the "Assets" directory was for help files and items like that.
I am trying to NOT muddy my values folders with the many help files that I am including and was using "activity.getAssets().open( file )" to read the files.
Also, some of these "Asset" files are different language pictures.
Can you put the files in /res instead of /assets? This has built in support for multiple languages, there is an easy to follow guide here.
Basically, if your original text is in /res/values/strings.xml, for example, you would put your translations in /res/values-{ISO LANGUAGE CODE}/strings.xml
For example, your French translation would be in /res/values-fr/strings.xml.
Android will pick the appropriate translation file according to the locale of the user's phone.
There are some good explanations of the other differences between /res and /assets here.
For the voice recognition in my app (using Vosk) I have defined the specific asset folder as resource string.
I.e. values\strings.xml contains:
<resources>
<string name="language_directory">vosk-model-small-en-us-0.15</string>
...
and values-de-rDE\strings.xml contains:
<resources>
<string name="language_directory">vosk-model-small-de-0.15</string>
...
So I can access the asset directory via
val assets = Assets(activity)
val assetDir = assets.syncAssets()
val modelDir = activity.getString(R.string.language_directory)
recognitionListener.model = Model("$assetDir/$modelDir")
This way the correct directory is always chosen based in the active locale.
In my case, those are located at models\src\main\assets\sync\<language_directory>
Make folder in assets:
1. htmlpagesNL
2. htmlpagesUS
Copy file from htmlpagesNL and paste to htmlpagesUS and Translate
Use url inside Nl string file:
file:///android_asset/htmlpagesNL for NL translation
Use url inside Us string file:
file:///android_asset/htmlpagesUS for US translation
Support different languages
Support different languages and cultures
I have text files in the raw folder that I would like to use in my app. I am using ListFragments and depending on what item is selected I want to load that files text in a new layout.
I can properly load the text fine but I would like to be able to scan the file previously so that I can have the first line of the file be the title that is displayed in the ListView. I have a method that determines the number of files in the raw folder and adds the names to the ArrayList.
Here is my method:
private void listRaw() {
Field[] fields = R.raw.class.getFields();
for (int count = 0; count < fields.length; count++) {
myArrayList.add(fields[count].getName());
}
}
The problem i am having is setting up a scanner. I do not know how to tell the scanner to scan this specific file. I tried making a new File object and used the Scanner(File) but I do not think I am declaring the file name properly nor if this is even the best way to get this done. Normally if you know the file name you can just simply do:
Scanner fileReader = new Scanner("filename");
but in this loop I never actually have the file name set.
I have text files in the raw folder that I would like to use in my app
I am assuming that "the raw folder" means the res/raw/ resource directory in your project.
I do not know how to tell the scanner to scan this specific file
That is because there is no file. The file exists on your development machine. The representation of the raw resource at runtime is just that: a raw resource. Under the covers, it's effectively an entry in a ZIP file.
You need to get the R.raw value for a raw resource, then use getResources().openRawResource() to get an InputStream that you can pass to a Scanner.
Unless you have different editions of these raw resources for different configurations (e.g., language), you might find it easier to work with the assets/ directory and AssetManager for packaging text files with your app.
I am really lost here, i am trying to find my way around xml parsing, reading and writing.
I have this app where at one point i can input data such as a Date and a time for instance - click save, and once it saved it will write into an existing XML file, for later reading, and add it at the end in a format like this:
<Units>
<item>
<date>27-5-12</date>
<time>15:30</time>
</item>
<item>
... and so on ...
</Units>
i managed to read an xml file, but i am really having trouble in opening a premade - existing file for reading or writing.
currently i tried this code:
InputStream raw = this.getAssets().open("mydata.xml");
Reader is = new BufferedReader(new InputStreamReader(raw, "UTF8"));
which returns file not found exception.
could anyone direct me on what i should look for?
Thanks.
As written, your source XML file is located in your APK's assets directory - everything in your APK is read-only, so you won't be able to write to that file. (Also, you should probably put that XML data into the res/xml directory instead of the assets directory, unless you have a compelling reason to do otherwise.)
If the XML file isn't very long/complex, you could read the assets file into a structure, then add your new data to that structure, and write a new XML file into your app's data directory with the updated data. This approach has the advantage that you can have multiple source files feeding into one main file per app.
A more flexible and open-ended option would be to set up a database table. When the app is first installed, you load/update the table with data from the assets file. As your app keeps adding timestamped data, you just add new rows to the table. This approach also has the advantage that you can easily update the source data or the database structure with each app update - it's harder to compare old vs new data if it's stored internally in XML format.
I didn't see the assets folder in my project, i placed my xml file there and it works now :)
I have 2 different functionality to be implemented as part of a single application.
They have different screen flows and BL to be implemented but a single apk,so it is transparent to the end user.
I have 100 screens for each of the flow,so can I have custom folder names in the resources directory for easy maintenance and loose coupling.
eg: res
-layout
-layout_savings
-layout_checking
-drawable
-drawable_savings
-drawable_cheking
currently we have only the following structure
res
-layout
-layout-land
-drawable
-values
Will there be any problem while generating the R.java file.
Any help would be appreciated.
for what you need , i suggest you to use the assets directory instead of res. in assets dir you can sort your files anyway you like (dir name/filename) . You access them with AssetManager.
this require a little change in code but i think this is the only way if you want to sort your file like that , res folder doesn't allow custom directory names.
(Or of course you can store files in the sdcard)