Getting to Know Web GIS. Pinde Fu
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(such as place-names and postal codes) into coordinates. If your data contains addresses for a single country, select its name from the Country list. If the addresses refer to multiple countries or to a country that is not on the Country list, select World. If ArcGIS Online didn’t pick up the correct location fields, you can click the wrong fields to make corrections.
1 When prompted to review addresses, click Yes.The feature layer will be added to the map viewer for you to review the geocoding results. You can click each of the matched addresses in the matched table at the bottom of the map and review its placement on the map. You can also click each of the unmatched addresses in the unmatched table, fix it by choosing a suggested address, or Edit the address information and choose a suggested address, or directly add a point to the map.In the tutorial data, all cities are matched to their correct locations.
2 Click Done Reviewing.You have created a hosted feature layer using geocoding.
3 Click the Save button to save your web map.
4 In the Save Map window, enter the appropriate title and tags, and then click Save Map.
You have created a hosted feature layer using geocoding. You can go to the layer details page to share the layer with everyone or other audience you select. In this tutorial, you will share the layer together with your web map later.
2.2 Configure layer style
In this section, you will explore smart mapping and configure your layer to display the population change rates in the 50 cities in your layer.
1 With the map viewer open, in the Contents pane, point to Top 50 US Cities Population, and then click the Change Style button .
2 In the Choose an attribute to show text box, choose Estimate2016 as the field to show in the Change Style pane.Note that smart mapping automatically selects Counts and Amounts (Size) as the default style for this numeric field. This style uses an orderable sequence of different sizes to represent your numerical data or ranked categories. You can symbolize points, lines, and areas using this approach. The proportional symbols make the map intuitive. On this map, can you easily tell the top three most populated cities in the US?Next, you will style the layer based on the ratio of two fields. You can do so using Arcade or selecting two fields. Here, you will select two fields.
3 Click Options in the Counts and Amounts (Size) style to further configure the layer style.
4 Set Divided By to Census2010.The map now displays the ratio of population 2016 to 2010, which is a good indicator of population growth over the years. Bigger circles indicate bigger increases, and smaller circles indicate smaller increases and even decreases. A value of 1.0 means there was no population change; numbers greater than 1.0 indicate population growth; and numbers less than 1.0 indicate population decline. This ratio is a good approach to reveal how things change over time without having to create multiple maps. This approach works for any numerical data from two time periods.You may also change the Min and Max symbol sizes and adjust the two handles on the histogram slider to exaggerate the cities with the most and the least population growth. Smart mapping easily emphasizes certain ranges of the data and uncovers subtle details.Smart mapping also uses continuous sizes and colors automatically, but it does not remove any of the traditional methods to break features into a set of classes and show them with a limited number of sizes and colors. Next, you will manually break the cities into classes and assign symbols for these classes.
5 Scroll down in the Change Style pane and select the box next to Classify Data. Select manual breaks with 4 classes and Round classes to 0.01 (in other words, round the class break values to 2 decimal points).
6 Starting from the bottom, set the class break values to 1, 1.1, and 1.15. You can set the values by clicking the existing break values and typing in the new values as illustrated or by dragging the handles on the histogram slider in Change Style.Note the Symbols and Legend icons in the figure. Clicking the Symbols icon allows you to set a symbol for all the classes. Clicking the Legend icon allows you to set an individual symbol and label for each class.All the classes are using the same symbol with gradual sizes. Next, you will set each class to use a different symbol.
7 Click Legend.This step allows you to edit the symbol for each individual class.
8 Click the biggest circle, in other words, the one next to > 1.15 to 1.2.A window appears showing the available point symbols.
9 After clicking the list to choose Arrows, click the solid red up arrow, set its size to 36, and click OK.The map viewer provides a collection of symbols for business, damage, disasters, infrastructure, recreation, people places, points of interest, health, transportation, and other categories, as shown in the list of options. You can browse through these categories and get a sense of the variety of available symbols. To browse, you can click the symbol list to access the options.
10 Similarly, make the following changes:For the > 1.1 to 1.15 class, change the symbol to a brown upper arrow in the Arrows group, set its size to 24, and click OK.For the > 1.0 to 1.1 class, change the symbol to a purple upper arrow in the Arrows group, set its size to 16, and click OK.
In addition to the collections of symbols, the map viewer allows you to use your own images as symbols. You will do so in the next steps.
1 Click the symbol for the 0.94 to 1 class, click Use an Image, specify https://i.imgur.com/OS8tZpq.gif (or the short equivalent http://bit.ly/2F0fQVq) as the URL, click the Plus icon, set its size to 16, and then click OK.The last class lost population from 2010 to 2016, so the class was symbolized using a solid down arrow.
2 Click OK, and then click Done to exit the Change Style pane.
3 In the Contents pane, point to the Top 50 US Cities layer, click the More Options button , and click Save Layer.This step saves the style to the layer item itself. When you add this layer to any web maps, the layer will carry the style you defined in this section as the default style.Next, you will change the basemap to a neutral background.
4 Click the Basemap button on the map viewer toolbar, and click Light Gray Canvas.This basemap provides a neutral background with minimal colors, labels, and features. This background allows your operational data layer to stand out clearly.
5 Save your web map.
You have configured the style of your operational layer. With this map, you can quickly and easily see which cities had population increases or decreases.
2.3 Configure a layer pop-up using ArcGIS Arcade
In this section, you will decide what information to show and how you will show the information in the cities’ pop-ups.
1 With your web map open in the map viewer, click one of the 50 cities to see the default pop-up.If a pop-up window does not appear, it may be disabled for this layer. You can enable the pop-up by pointing to the layer, clicking the More Options button and clicking Enable Pop-up.This default pop-up is useful, but you can enhance the window to communicate information in more intuitive and engaging ways.
2 In the Contents pane, point to the Top 50 US Cities layer, click the More Options button , and click Configure Pop-up.The Configure Pop-up pane appears, in which you can configure the pop-up’s title, contents, and media sections. Next, you will configure the title, which can be static text, a set of attribute field values, or a combination of the two.
3 Click the Plus button under Pop-up Title to select the City field. Type a comma and a space, and click the Plus button again to select the State field.Next, you will configure the pop-up contents, which can include a list of attribute fields or a custom description based on attribute