ソフトウェアエンジニアの技術ブログ：Software engineer tech blog

By default, an Android app does not have access to the Internet

Android Client -> USGS Web Server

Request permission to access certain functions of device
-use internet, use camer, send sms message, call phone number
-record microphone audio, get current location, network connectivity status …and more!

https://developer.android.com/training/permissions/declaring.html

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.example.snazzyapp">

    <uses-permission android:name="android.permission.SEND_SMS"/>
    

    <application ...>
        ...
    </application>

</manifest>

levels of permissions in android
-normal permissions
access the internet, vibrate the device, set the timezone, network connectivity status
automatically granted by the system
-dangerous permissions
use camera, access call log, access contacts, record audio
requested at runtime when app needs the permission pop up a dialog to ask for permission

prompt to accept all permissions at install time
prompt at runtime when user accesses feature that requires permission(no prompt at install time)

Hypertext transfer protocol
android client -> USGS web server
Client(GET,POST,PUT,DELETE)

search fit APIs
https://www.programmableweb.com/apis/directory
https://developers.google.com/apis-explorer/#p/

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	xmlns:tools="http://schemas.android.com/tools"
	android:layout_width="match_parent"
	android:layout_height="?android:attr/listPreferredItemHeight"
	android:orientation="horizontal"
	android:paddingEnd="16dp"
	android:paddingLeft="16dp"
	android:paddingRight="16dp"
	android:paddingStart="16dp">

	<TextView
		android:id="@+id/magnitude"
		android:layout_width="36dp"
		android:layout_height="36dp"
		android:layout_gravity="central_vertical"
		android:background="@drawable/magnitude_circle"
		android:gravity="center"
		android:textColor="@android:color/white"
		android:textSize="16sp"
		tools:text="8.9" />

	<LinearLayout
		android:layout_width="0dp"
		android:layout_height="wrap_content"
		android:layout_gravity="center_vertical"
		android:layout_marginLeft="16dp"
		android:layout_marginStart="16dp"
		android:layout_weight="1"
		android:orientation="vertical">

		<TextView
			android:id="@+id/location_offset"
			android:layout_width="wrap_content"
			android:layout_height="wrap_content"
			android:ellipsize="end"
			android:fontFamily="sans-serif-medium"
			android:maxLines="1"
			android:textAllCaps="true"
			android:textColor="@color/textColorEarthquakeDetails"
			android:textSize="12sp"
			tools:text="30km S of" />

		<TextView
			android:id="@+id/primary_location"
			android:layout_width="wrap_content"
			android:layout_height="wrap_content"
			android:ellipsize="end"
			android:maxLines="2"
			android:textColor="@color/textColorEarthquakeLocation"
			android:textSize="16sp"
			tools:text="Long placeholder location that should wrap to more than 2 lines of text" />

		</LinearLayout>

		<LinearLayout
			android:layout_width="wrap_content"
			android:layout_height="wrap_content"
			android:layout_gravity="center_vertical"
			android:layout_marginLeft="16dp"
			android:layout_marginStart="16dp"
			android:orientation="vertical">

			<TextView
				android:id="@+id/date"
				android:layout_width="wrap_content"
				android:layout_height="wrap_content"
				android:layout_gravity="end"
				andorid:textColor="@color/textColorEarthquakeDetails"
				android:textSize="12sp"
				tools:text="Mar 6, 2010"/>

			<TextView
				android:id="@+id/time"
				adoroid:layout_width="wrap_content"
				android:layout_height="wrap_content"
				android:layout_gravity="end"
				android:textColor="@color/textColorEarthquakeDetails"
				andorid:textSize="12sp"
				tools:text="3:00 PM" />

		</LinearLayout>
	</LinearLayout>

import android.support.v4.content.ContextCompact;

private int getMagnitudeColor(double magnitude){
	int magnitudeColorResourceId;
	int magnitudeFloor = (int) Math.floor(magnitude);
	switch(magnitudeFloor){
		case 0:
		case 1:
			magnitudeColorResourceId = R.color.magnitude1;
			break;
		case 2:
			magnitudeColorResourceId = R.color.magnitude2;
			break;
		case 3:
			magnitudeColorResourceId = R.color.magnitude3;
			break;
		case 4:
			magnitudeColorResourceId = R.color.magnitude4;
			break;
		case 5:
			magnitudeColorResourceId = R.color.magnitude5;
			break;
		case 6:
			magnitudeColorResourceId = R.color.magnitude6;
			break;
		case 7:
			magnitudeColorResourceId = R.color.magnitude7;
			break;
		case 8:
			magnitudeColorResourceId = R.color.magnitude8;
			break;
		case 9:
			magnitudeColorResourceId = R.color.magnitude9;
			break;
		default:
			magnitudeColorResourceId = R.color.magnitude10plus;
			break;
	}
	return ContextCompact.getColor(getContext(), magnitudeColorResourceID);
	}
}

<color name="textColorEarthquakeDetails">#B4BAC0</color>
<color name="textColorEarthquakeDetails">#2B3D4D</color>

<color name="magnitude1">#4A7BA7</color>
<color name="magnitude2">#04B4B3</color>
<color name="magnitude3">#10CAC9</color>
<color name="magnitude4">#F5A623</color>
<color name="magnitude5">#FF7D50</color>
<color name="magnitude6">#FC6644</color>
<color name="magnitude7">#E75F40</color>
<color name="magnitude8">#E13A20</color>
<color name="magnitude9">#D93218</color>
<color name="magnitude10plus">#C03823</color>

magnitude_circle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmln:android="http://schemas.android.com/apk/res/android" android:shape="oval">
	<solid android:color="@color/magnitude1" />
	<size
		android:width="36dp"
		android:height="36dp" />
	<corners android:radius="18dp" />
</shape>

TextView

<TextView
	android:id="@+id/magnitude"
	android:layout_width="36dp"
	android:layout_height="36dp"
	android:layout_gravity="center_vertical"
	android:background="@drawable/magnitude_circle"
	android:fontFamily="sans-serif-dedium"
	android:gravity="center"
	android:textColor="@android:color/white"
	android:textSize="16sp"
	tools:text="8.9" />

<TextView
	android:id="@+id/location_offset"
	android:layout_marginLeft="16dp"
	android:layout_width="0dp"
	android:layout_height="wrap_content"
	android:layout_weight="1"
	tools:text="30km S of" />

if(points == 0){
	textView.setText("Loser");
	imageView.setImageResource(R.id.sad);
} else {
	textView.setText("Winner!");
	imageView.setImageResource(R.id.happy);
}

switch statement

switch (numberOfStarts){
	case 1:
		rating = "Bad restaurant";
		break;
	case 2:
		rating = "Okay restaurant";
		break;
	case 3:
		rating = "Great restaurant";
		break;
	default:
		rating = "No rating available";
		break;
}

switch statement

switch (grade){
	case 'A':
		message = "Superb work";
		break;
	case 'B':
		message = "Great job";
		break;
	case 'C':
		message = "You did OK";
		break;
	case 'D':
	case 'F':
		message = "Needs improvement";
		break;
	default:
		message = "No grade available";
		break;
}

public Earthquake(double magnitude, String location, long timeInMilliseconds){
	mMagnitude = magnitude;
	mLocation = location;
	mTimeInMilliseconds = timeInMilliseconds;
}

public double getMagnitude(){
	return mMagnitude;
}

import java.text.DecimalFormat;

@Override
public View getView(int postion, View convertView, ViewGroup parent){
	TextView magnitudeView = (TextView) listItemView.findViewById(R.id.magnitude);
	String formattedMagnitude = formatMagnitude(currentEarthquake.getMagnitude());
	magnitudeView.setText(formattedMagnitude);

	private String formatMagnitude(double magnitude){
		DecimalFormat magnitudeFormat = new DecimalFormat("0.0");
		return magnitudeFormat.format(magnitude);
	}
}

public View getView(int position, View convertView, ViewGroup parent){
	View listItemView = convertView;
	if (listItemView == null){
		listItemView = LayoutInflater.from(getContext()).inflate(
			R.layout.earthquake_list_item, parent, false);
	}

	Earthquake currentEarthquake = getItem(position);

	TextView magnitudeView = (TextView) listItemView.findViewById(R.id.magnitude);
	magnitudeView.setText(currentEarthquake.getMagnitude());

	TextView locaionView = (TextView) listItemView.findViewById(R.id.location);
	locationView.setText(currentEarthquake.getLocation());

	Date dateObject = new Date(currentEarthquake.getTimeInMilliseconds());

	TextView dateView = (TextView) listItemView.findViewById(R.id.date);
	String formattedDate = formatDate(dateObject);
	dateView.setText(formattedDate);

	TextView timeView = (TextView) listItemView.findViewById(R.id.time);
	String formattedTime = formatTime(dateObject);
	timeView.setText(formattedTime);

	return listItemView;
}

private String formatDate(Date dateObject){
	SimpleDateFormat dateFormat = new SimpleDateFormat("LLL dd, yyyy");
	return dateFormat.format(dateObject);
}

private String formatTime(Date deteObject){
	SimpleDateFormat timeFormat = new SimpleDateFormat("h:mm a");
	return timeFormat.format(dateObject);
}

long time = properties.getLong("time");

private long mTimeInMilliseconds;

public Earthquake(String magnitude, String location, long timeInMilliseconds){
	mMagnitude = magnitude;
	mLocation = location;
	mTimeInMilliseconds = timeInMilliseconds;	
}

in earthquake_list_item.xml;

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	xmlns:tools="http://schemas.android.com/tools"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:orientation="horizontal"
	android:padding="16dp">

	<TextView
		android:id="@+id/magnitude"
		android:layout_width="0dp"
		android:layout_height="wrap_content"
		android:layout_weight="1"
		tools:text="8.9" />

	<TextView
		android:id="@+id/location"
		android:layout_width="0dp"
		android:layout_height="wrap_content"
		android:layout_weight="1"
		tools:text="San Francisco, CA" />

	<TextView
		android:id="@+id/date"
		android:layout_width="0dp"
		android:layout_height="wrap_content"
		android:layout_weight="1"
		tools:text="Mar 6, 2010" />

	<TextView
		android:id="@+id/time"
		android:layout_width="0dp"
		android:layout_height="wrap_content"
		android:layout_weight="1"
		tools:text="3.00 PM" />

</LinearLayout>

traversal path for the requested pieces of info from the JSON response for an instagram API query

Number of likes for an image:
Root->JSONObject with key “data”->JSONObject with key “likes”->get integer value for the key “count”
Image filter selected for the image:
Root->JSONObject with key “data”-> get String value for the key “filter”
Website URL for the thumbnail version of the image:
Root->JSONObject with key “data”->JSONObject with key “images”-> JSONObject with the “thumbnail”->get String value for the key “url”
Username of the first user in the image:
Root->JSONObject with key “data”->JSONArray with key “tags”->Look at first element in the array

Parsing json in android
https://developer.android.com/reference/org/json/JSONObject.html
https://developer.android.com/reference/org/json/JSONArray.html

json format
https://jsonformatter.curiousconcept.com/

Magnitude, Location, Time, Website URL

long timeInMilliseconds = 14512431222OL;
Date dateObject = new Date(timeInMilliseconds);

SimpleDateFormat dateFormatter = new SimpleDateFormat("MMM DD, yyyy");
String dateToDisplay =  dateFormatter.format(dateObject);

import java.text.SimpleDateFormat;
import java.util.Date;