From f87d585e131d98c92f3856e0e76b510886b8619f Mon Sep 17 00:00:00 2001 From: jgzuke Date: Sun, 10 Apr 2016 18:18:44 -0700 Subject: [PATCH] add back android --- mobile/android/Android_Studio_Setup.md | 18 + mobile/android/Android_Studio_Tips.md | 9 + mobile/android/Beautify_App.md | 36 ++ mobile/android/Caching_Data.md | 4 + mobile/android/Found_Caches_Page.md | 320 ++++++++++++++ mobile/android/Geocaching_App.md | 172 ++++++++ mobile/android/Geocaching_App_Extentions.md | 4 + mobile/android/Java_Introduction.md | 452 ++++++++++++++++++++ mobile/android/Map_Page.md | 332 ++++++++++++++ mobile/android/Putting_it_Together.md | 102 +++++ mobile/android/README.md | 25 ++ mobile/android/Settings_Page.md | 124 ++++++ mobile/android/Using_Libraries.md | 28 ++ mobile/android/Vocabulary.md | 63 +++ 14 files changed, 1689 insertions(+) create mode 100644 mobile/android/Android_Studio_Setup.md create mode 100644 mobile/android/Android_Studio_Tips.md create mode 100644 mobile/android/Beautify_App.md create mode 100644 mobile/android/Caching_Data.md create mode 100644 mobile/android/Found_Caches_Page.md create mode 100644 mobile/android/Geocaching_App.md create mode 100644 mobile/android/Geocaching_App_Extentions.md create mode 100644 mobile/android/Java_Introduction.md create mode 100644 mobile/android/Map_Page.md create mode 100644 mobile/android/Putting_it_Together.md create mode 100644 mobile/android/README.md create mode 100644 mobile/android/Settings_Page.md create mode 100644 mobile/android/Using_Libraries.md create mode 100644 mobile/android/Vocabulary.md diff --git a/mobile/android/Android_Studio_Setup.md b/mobile/android/Android_Studio_Setup.md new file mode 100644 index 0000000..c65ca84 --- /dev/null +++ b/mobile/android/Android_Studio_Setup.md @@ -0,0 +1,18 @@ +## Setup Android Studio +###Download/Install Android Studio +To build our Android app we'll be using an IDE called Android Studio. An IDE is a programming environment that allows you to edit files, compile and run your code, and has other features built into it like debugging. Lets start by [Downloading Android Studio](http://developer.android.com/training/basics/firstapp/index.html) To get it to work you'll also need to install [Java](TODO:link). + +###Download SDK tools +TODO: SDK stuff here or after? test fresh install studio on windows. + +###Setting up a New Project +Once Android studio is set up we'll need to start a [New Project](http://developer.android.com/training/basics/firstapp/creating-project.html). Open Android studio and select 'Start a new Android Studio Project', use a Minimum SDK of API 16 (Jelly Bean), and when prompted to choose starting Activity, choose 'Empty Activity' +Minimum SDK is the minimum version of the Android Operating System required to run your app. We chose 16 because most phones run that or newer, and it allows us to use new Android features. +The starting Activity is the code that Android Studio will generate to start your project. Well explain what Activity and Fragment are in a bit. +Android studio should now generate your starting project, once it finishes indexing (loading bar at the bottom of the screen) it will drop you into the screen pictured below (TODO: Get screenshot from windows AS). + +### Running project on Device/Emulator +To make sure it worked correctly, click the green 'Run' arrow at the top of the screen. This will compile the starting code and prompt you for a device to run it on. If you are using the emulator for testing, check Launch Emulator at the bottom and click OK, this will start a virtual device and run the app on it (may take while to start). If you are using a real device, plug in your phone and accept the prompt on the device, then it should appear under 'Choose a running device'. Select it and click OK to run the app on your phone. Your app should open with a white screen that says 'Hello World'. (TODO: add picture) + +### Problems? +Thats what mentors are here for, feel free to ask for help with any problems you have, if you feel up to the challenge you can also try searching your problem on [StackOverflow](http://stackoverflow.com/) or just Google. diff --git a/mobile/android/Android_Studio_Tips.md b/mobile/android/Android_Studio_Tips.md new file mode 100644 index 0000000..ca96542 --- /dev/null +++ b/mobile/android/Android_Studio_Tips.md @@ -0,0 +1,9 @@ +## Android Studio Tips +### Android studio view (structure project preview) +- Project (left): Shows files in android structure +- Structure (right): Shows functions and inner classes of files +- Android (bottom right): Shows logs from device +- Run (bottom left): Options for running project +- Terminal (bottom left): Command line + +### [Android studio shortcuts](https://teamtreehouse.com/library/android-tools/getting-started-with-android-studio/helpful-keyboard-shortcuts) \ No newline at end of file diff --git a/mobile/android/Beautify_App.md b/mobile/android/Beautify_App.md new file mode 100644 index 0000000..7ec5b4b --- /dev/null +++ b/mobile/android/Beautify_App.md @@ -0,0 +1,36 @@ +# Beautify app +## Colors +### Defining colors in colors.xml +- Colors + +### Using Colors in Layouts +- Change text color + +### Using Colors in Java +- Change Map properties if possible? + +## Themes +### Create Dark/Light Theme +- Create new colors +- Define theme + +### Using Theme +- Use theme attributes in styles + +### Add Theme to Settings +- If made settings + +## Defining Styles +### Defining Styles +- Text Style2 +- CardStyle +- Button Style + +### Using styles + +## Portrait/Landscape Layouts +### Dimensions +- Use Dimens for different sizes + +### Alternate Layouts +- Use Alternate layout for found screen diff --git a/mobile/android/Caching_Data.md b/mobile/android/Caching_Data.md new file mode 100644 index 0000000..d50fd3c --- /dev/null +++ b/mobile/android/Caching_Data.md @@ -0,0 +1,4 @@ +# Cacheing Data +- Store json to use off network +- Take in onError Callbacks +- Check connectivity \ No newline at end of file diff --git a/mobile/android/Found_Caches_Page.md b/mobile/android/Found_Caches_Page.md new file mode 100644 index 0000000..0a66a4f --- /dev/null +++ b/mobile/android/Found_Caches_Page.md @@ -0,0 +1,320 @@ +# Found Caches Page +## RecyclerView +### Add the RecyclerView to Layout +Lets start with building the found caches page, basically this page is a list of the name and difficulty of caches you have found. We will build this list with what is called a `RecyclerView`, lets add one to our found caches layout underneath our Button. +``` xml + +``` + +### Getting the Support Design Library +To use `RecyclerView` you need to grab some code that doesnt come packaged with android, we will do this through `gradle`. In the project tab on the left there is a section called 'Gradle Scripts', open up `build.gradle (Module: app)`. `Gradle` is Android's build system that you can also use to automate some build related tasks. Basically it takes our Java code and XML and packages them into an APK that you can run on your phone, we wont be working with it much today besides using it to fetch code like we are now. In the `dependencies` section add `compile 'com.android.support:design:23.2.0'`, this will allow us to use elements from the support design library (version 23.2.0) by including it when we build our app. + +### What is RecyclerView +`RecyclerView`s are a bit tricky to work with, lets take a look at what they are before we dive in. To work a `RecyclerView` needs an `Adapter`, `LayoutManager`, `ViewHolder`, a list of data to display, and a layout to show it in. It will show this data as a list of `Views` + +**Adapter:** When a `RecyclerView` is displayed it asks its `Adapter` to create `View`s from the data it has until it fills the screen completely. As the user scrolls the `Adapter` 'recycles' the `View`s that go off screen to make new ones by changing the data in the `View`'s `ViewHolder`, and gives the `View` back to the `RecyclerView` to show. + +**ViewHolder:** The `ViewHolder`s are attached to each `View` and when given an entry from the data list 'bind' the data to their `View`, meaning it sets the information in the `View` based on the data it received. + +**Data List:** The `RecyclerView` needs a data entry for every element is displays in its list, this data will be used to show the proper `Views` through the `ViewHolder`s. + +**Layout:** The `RecyclerView` needs a layout to inflate for the items it will display. For our first example we will use a `TextView`, later we will made our own layout. + +**LayoutManager:** The `LayoutManager` tells the `RecyclerView` how to lay out or display its list of items. + +### LayoutManager +Back in FoundCachesFragment, get a reference to the `RecyclerView` the same way as we did the `Button` or `TextView`. Lets start by setting our `LayoutManager` like so `yourRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));`, you wont have to worry about what this is doing but basically LinearLayoutManager means the data will display in a straight vertical list. + +### ViewHolder +Our RecyclerView will be really simple for now, we'll show a List of `TextView`s which means our `ViewHolder` will be pretty simple. Classes inside files, or 'inner' classes are defined the same place a method would go. +``` java +private class CacheHolder extends RecyclerView.ViewHolder { + + // We will modify the text in this TextView when we get bound to data + private final TextView nameTextView; + + // itemView is the View this ViewHolder controls + public CacheHolder(TextView itemView) { + super(itemView); + nameTextView = itemView; + } + + // This is called when a View is recycled and given new data, or first created + // cacheName will be from our data list + public void bindCache(String cacheName) { + nameTextView.setText(cacheName); + } +} +``` +Our `ViewHolder` will be created with a `View` that it will then modify when it is Bound to some data. In this case the data is just the name of the cache, later on we will bind a data object to this view that will have all the information we want to display about it. + +### Adapter +Our adapter is responsible for inflating or recycling `View`s for the `RecyclerView` to display, as well as keeping track of the data definind the list. This class is a bit longer but still fairly simple. +``` java +private class CacheAdapter extends RecyclerView.Adapter { + + // This is our list of data + private List itemNames; + + // Our adapter is created with this data list to display + public CacheAdapter(List itemNames) { + this.itemNames = itemNames; + } + + // Called when a new view needs to be created, creates a View and ViewHolder + @Override + public CacheHolder onCreateViewHolder(ViewGroup parent, int pos) { + TextView view = new TextView(getContext()); + return new CacheHolder(view); + } + + // Binds a given ViewHolder to data at the same position in the list + @Override + public void onBindViewHolder(CacheHolder holder, int pos) { + String name = itemNames.get(pos); + holder.bindCache(name); + } + + // If we have no value for itemNames we cant create any items, + // otherwise we can create as many as we have data point + @Override + public int getItemCount() { + if (itemNames == null) { + return 0; + } + return itemNames.size(); + } +} +``` + +### Data List +The last thing we have to do to make our `RecyclerView` work is give it data, and set the `Adapter`. Becuase our adapter just has a list of names, lets make an `ArrayList` of names and add some. +``` java +ArrayList itemNames = new ArrayList<>(); +itemNames.add("Cache 1"); +// Add more elements to data list +``` +Then all have have to do to put everything together is create and set your `Adapter`. +``` java +yourRecyclerView.setAdapter(new CacheAdapter(itemNames)); +``` +You should now have a working recycler view, make sure it compiles and runs correctly, you should see your names that you put in `itemNames` underneath your `Button` + +## Getting Data +### JSON +Now that we have our `RecyclerView` its time to get some real data to put in it, eventually were going to be getting this data from our server online, but for now were going to read the data from a file locally in resources. The format were going to store our data in is called JSON, basically it's a way to write our data that is easy for us to read, as well as for a computer to use. +``` json +{ + "Cache 1": { + "name": "Cache 1", + "difficulty": 3, + "found": 1456883400000 + }, + "Cache 2": { + "name": "Cache 2", + "difficulty": 3, + "found": 1456531200000 + }, + "Cache 3": { + "name": "Cache 3", + "difficulty": 3, + "found": 1456531200000 + } +} +``` +This is what the JSON file looks like for our found caches, lets go through whats happening here. In JSON, everything is stored by some 'key' like in a `Map`. Our first element has the key `Cache 1` and the value +``` json +"name": "Cache 1", +"difficulty": 3, +"found": 1456883400000 +``` +Each of these values still maps a key, for example `difficulty` to a value `3`. We will be using the cache names as their keys. + +## Create JSON Resource +Now that we know a bit about JSON lets start using it, create a new 'Android Resource Directory' in `res` called `raw` with resource type `raw`, then inside `raw` (you might have to refresh the menu to see it) create a file called `caches_found.json`. Copy the response from before into this file. +``` json +{ + "Cache 1": { + "name": "Cache 1", + "difficulty": 3, + "found": 1456883400000 + }, + "Cache 2": { + "name": "Cache 2", + "difficulty": 3, + "found": 1456531200000 + }, + "Cache 3": { + "name": "Cache 3", + "difficulty": 3, + "found": 1456531200000 + } +} +``` + +## Reading from Resources +Since we dont want to make our `FoundCachesFragment` too large we'll write our code to load this JSON file ielsewhere create a new Java Class in your java folder with `MainActivity` and `FoundCachesFragment` called `DataUtilities`. This is where we will write all our code related to reading, and later fetching and sending data. Lets write a method called `getFoundCaches` inside this class that takes in a `Context` like so `public static void getFoundCaches(Context context) {`. This method is `static` meaning that it can be called without an instance of the class like so `DataUtilities.getResponseText(context)`. When reading from raw resources we use something called an `InputStream` to read the file, The next block of code seems scary and I wont go into how it works, but it reads the json file `caches_found` we wrote earlier into a `String` called `json`. +``` java +try { + InputStream is = context.getResources().openRawResource(R.raw.caches_found); + int size = is.available(); + byte[] buffer = new byte[size]; + is.read(buffer); + is.close(); + String json = new String(buffer, "UTF-8"); +} catch (IOException ex) { + ex.printStackTrace(); +} +``` +The `try` and `catch` are keyword we use if something might go wrong. We try to run the code in the first block and if something goes wrong trying to read the file the system will 'throw' and `IOException` object that would normally crash the app. If this happens within the first block we instead 'catch' the exception, give up on what we were trying to do and run some other code instead. In this example we print out the exceptions 'stack trace' which is a log of what went wrong to cause the exception to get thrown. + +## Serializing JSON Objects +Now we have a String of our JSON file, which is really hard to use as is. What were going to do now is convert this String to a more useable object, a `Map` of cache names to `FoundCache` objects, which will have `name`, `difficulty` and `found` as variables. What were going to use to do this is a tools called Gson, which will take our String and automatically convert it to an object we define. Lets start by creating our 'model' object that mirrors how our JSON data is set up. Create a new Java class called `FoundCache` that looks like we just described. +``` java +public class FoundCache { + public String name; + public int difficulty; + public long found; +} +``` +When using Gson the variable names we use here have to match the keys in the JSON file. + +To use Gson we have to include it with `gradle`, add `compile 'com.google.code.gson:gson:2.3'` to the gradle file the same place we did before. Now if we go back to `DataUtilities` we can add +``` java +Gson gson = new Gson(); +// This responseType is what we will convert our json into, a 'Map' +Type responseType = new TypeToken>() {}.getType(); +Map foundCacheMap = gson.fromJson(json, responseType); +``` +underneath `String json = new String(buffer, "UTF-8");`, notice the method `fromJson` takes `responseType` as a parameter which tells gson what type of object it is creating. We now have a method that reads our JSON file and gets an object with the information we need to fill our `RecyclerView`. + +## Callbacks +Now that we have a way to get this data let's send it to our `FoundCachesFragment`. The easiest way to do this would be to return the object from the function, but this causes problems later on when we get the information from online. When we call a method our phone waits till it finishes before moving on to do anything else, this causes issues if it takes a while for the method to finish as it would freeze your phone until it was done. We can get around this by running our code on a seperate 'thread' which we'll explain later, but that means we cant return from this method. + +What we do instead is define a 'callback', an object that defines a function to run when something happens like our OnClickListener running code when our `Button` got clicked. To create a callback we define an `interface` with one method `onResults(Map results)` which we will call when we finish serializing the JSON file. +``` java +public interface FoundCachesReceiver { + void onResults(Map results); +} +``` +Add this to DataUtilities above the method `getFoundCaches`. When we call `getFoundCaches` we want to get a callback to send back the data with so add `FoundCachesReceiver receiver` as a parameter to the `getFoundCaches` method and add `receiver.onResults(foundCacheMap);` after serializing our JSON file. Now our method takes in a callback, and fires its function when it has the data ready. + +## Using DataUtilities +In our `FoundCachesFragment` we can now get the list of found caches easily by calling +``` java +DataUtilities.getFoundCaches(getContext(), new DataUtilities.FoundCachesReceiver() { + @Override + public void onResults(Map results) { + // Do something with the results + } +}); +``` + +## Display Cache names in RecyclerView +Since we want this list to get displayed in the `RecyclerView` let's modify it a bit to take in `FoundCache` values instead of `String`s. First change the `CacheAdapter` constructor to take in a `List` of `FoundCache`s, also change the type of the `items` variable. The last thing we have to do to in the `Adapter` is change `String item = items.get(pos);` to `FoundCache item = items.get(pos).name;` in `onBindViewHolder`. Next in `CacheHolder` modify `bindCache` to take in a `FoundCache cache` and display `cache.name`. The last thing we have to do is supply the right data. Let's replace +``` java +ArrayList itemNames = new ArrayList<>(); +itemNames.add("Cache 1"); +itemNames.add("Cache 2"); +itemNames.add("Cache 3"); +cachesRecycerViewAdapter = new CacheAdapter(itemNames); +cachesRecycerView.setAdapter(cachesRecycerViewAdapter); +``` +with the DataUtilities call from before, and where we have `// Do something with the results` we can create an adapter from our fetched data +``` java +// This takes our Map and makes a List of the values +List caches = new ArrayList(results.values()); +cachesRecycerViewAdapter = new CacheAdapter(caches); +cachesRecycerView.setAdapter(cachesRecycerViewAdapter); +``` +Try running the app and make sure it works, for now it should display the names of the caches (`Cache 1`, `Cache 2`, `Cache 3`) + +## Cache info Layout +Let's continue by showing the rest of the data in our list. To do this we'll first need something to display the data in, create a layout called `found_cache_list_item` or something similar under res/layouts (Note that you can't use capital letters or spaces in resource names). Because creating layouts can be time consuming I've created this one for you to copy into your new file. +``` xml + + + + + + + + + + + + +``` +Theres a few things here you haven't seen before, lets list them quick. +- `CardView`: a special layout that shows its contents in 'cards', if you want to see what this looks like switch to the design view. +- `layout_margin`: similar to padding, but pushes other elements away from it rather than making itself bigger to fit its contents with space inside. Defined in `dp` or Density-independent Pixels which are a size unit that scales with pixel density on the screen (`dp` stays the same physical size). +- `textSize`: fairly self explanatory, this sets the text size in `sp` which is similar to `dp` but takes users font size into consideration. +- `layout_marginEnd` and `layout_toEndOf`: not all phones are layed out right to left, if it isn't then `End` refers to the end of the layout which would be right for us. `layout_marginStart` or `layout_toStartOf` would be the opposite. + +To use `CardView` we need to add `compile 'com.android.support:cardview-v7:23.2.0'` to our gradle file to fetch the code we need the same way we did `gson` and the design library. + +## Using the Cache info Layout +Now that we have our layout let's put it to use, go back to our `CacheAdapter` and where we have `TextView view = new TextView(getContext());` we will inflate our new layout instead `View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.found_cache_list_item, parent, false);`. + +We should also modify our `CacheHolder` to give it two extra variables `difficultyTextView;` and `findTimeTextView;` both of which are `TextView`s, these will come from the layout we just defined. In the constructor change `TextView itemView` to `View itemView` and set `nameTextView = (TextView) itemView.findViewById(R.id.cache_name);`, doing the same for the other two variables using `R.id.cache_difficulty` and `R.id.cache_find_time` as the element Ids. Now we have all the data we need to display, in `bindCache` add +``` java +difficultyTextView.setText(Integer.toString(cache.difficulty)); +findTimeTextView.setText(Long.toString(cache.found)); +``` + +## Formatting and FormattingUtilities +If we run our app now it shows a list of all our data but not in a format that we can read, Lets creat another class called `FormattingUtilities` where we'll put any methods we use to format data to be readable. First lets add two methods to format difficulties and find times, each will take in the data we have and output a `String` that we can display. +``` java +public static String getDifficultyString(int difficulty, Context context) { + return ""; +} + +public static String getTimeAgoString(long timestamp, Context context) { + return ""; +} +``` +Notice that these methods are both `static` meaning that this class doesn't need to be instantiated to use these methods. Both methods also take in a `Context` which will be used to get `String`s from resources. + +Let's add two new entries in `strings.xml` that will be used in our cards with values `Found %s` and `Difficulty %d of 5`, you can pick names for them that make sense. Remember from before that `%d` is a number placeholder, `%s` is a placeholder but for a `String`. + +Back in FormattingUtilities `getDifficultString` will work the same way as our button click counter did before, simply return `context.getString(R.string.difficulty_out_of_five, difficulty)` and it will fill in the placeholder with our difficulty. For `getTimeAgoString` we're going to use something bulid into Android called called DateUtils to format our time nicely. `DateUtils.getRelativeTimeSpanString(context, timestamp).toString();` returns a `String` which formats our time nicely eg. "42 minutes ago". Inject this value into our other `String` the same way we did the number placeholder by using `getString` and passing the result of `getRelativeTimeSpanString`. + +If we go back to our `CacheHolder` we can replace our `Integer.toString` and `Long.toString` with `FormattingUtilities.getDifficultyString(cache.difficulty, getContext())` and `getTimeAgoString(cache.found, getContext())`. + +Try running the app, you should see our list of caches display with all the data from our `caches_found.json`. + +## Cleaning up +We're finished work on the 'Found' page for now, if you feel like it go through and take out the stuff we added at the start, `helloWorldTextView` + `clickMeButton` in our `FoundCachesFragment` fragment and `my_text_view` + `my_button` in the `fragment_found_caches` layout. diff --git a/mobile/android/Geocaching_App.md b/mobile/android/Geocaching_App.md new file mode 100644 index 0000000..ca1011d --- /dev/null +++ b/mobile/android/Geocaching_App.md @@ -0,0 +1,172 @@ +# Building the GeoCaching App +## What are we making +Now that we have an app compiling and running, lets start customizing it to make our Geocaching app. In our app we will have three screens shown below, a list of caches the user has found, a map showing caches at their locations, and a settings page. +TODO: add pics + +## Whats here now +If you open up the project tab on the left you will be able to view all the files in the project, for the most part we will be worried about files in java folder which will be your code, and files in the res (resources) folder which will define how your views are laid out and a few other things like colors, images, and text. To start we will look at the Fragment and Activity that we start with, and the xml layouts that go with them. + +### MainActivity.java +Activities in Android are entry points into the app that let you show something on the screen, and interact with the system. If you open up MainActivity under the java/yourApplicationName folder you will see the following. +``` java +package com.example.jzukewich.geocaching; + +import android.support.v7.app.AppCompatActivity; +import android.os.Bundle; + +public class MainActivity extends AppCompatActivity { + + @Override + protected void onCreate(Bundle savedInstanceState) { + super.onCreate(savedInstanceState); + setContentView(R.layout.activity_main); + } +} +``` +The first line, `package com...` is where our file is located in the project, we wont worry about this. Our imports are Android built in classes that we need, like when we used `import java.util.Arraylist;` before. In `onCreate`, which you might notice Overrides the method from `MainActivity`'s parent class `AppCompatActivity`, we call `AppCompatActivity`s onCreate and the method `setContentView` that sets the screen to show `R.layout.activity_main`, our activity's view. `R` means resources, so we can find this file in `res/layout/activity_main`, lets go take a look. + +### activity_main.xml +Welcome to XML, this is how we usually define our Views in Android. XML allows us to set values like width, height, text, and a bunch more depending what kind of View we are describing. In this case, our Activity's View is very simple, all it is displaying is one line of text, which says "Hello World!". +``` xml + + + + +``` +` + +