Drawable folder designer5/17/2023 Double click and change the text to "Find restaurants". We’ll place it at the bottom center of the layout. Next, let’s drag and drop a Button view from the Palette menu into our layout. Using dps helps our apps to look consistent across devices. Because Android devices have a variety of different screen resolutions, using pixels would result in views that would appear very small on the higher density devices and much larger on lower density devices. dp stands for density independent pixel and it is the unit of measurement we will use when specifying the size of our views in Android. Īs you can see, the layout_marginTop property was automatically set to a value of 35dp when we repositioned the TextView. To switch to the text view, select the text tab at the bottom of the Palette. Let’s take a look at the resulting XML by switching to the text view. We’ll change it to the name of our app, "MyRestaurants", and then reposition it so that it is centered horizontally. To change the text, double click the TextView. As we covered previously, a view is anything on the screen that we can see and/or interact with such as TextViews, Buttons, ImageViews, and so on. Each of these elements is what we will refer to in Android as a view. Let’s now change the existing "Hello World!" text and add a button. Altering the activity_main LayoutĪfter switching to the Text editor of our newly-created Relative Layout, we should see something like this:Īt any point, we can also toggle back to the Design tab to preview what our layout XML looks like. Make sure to go back and revisit the Creating Relative Layouts lesson if any of this feels unclear. Select the Text tab to toggle into the XML editor. Near the bottom-left of the screen you should see two tabs reading Design and Text (see image below). To edit our layout's XML directly, we'll need to navigate out of the visual editor and into the XML editor. However, Android Studio will likely default to the visual editor we saw our Constraint Layout in earlier. The remaining two fields can remain the same. In the Root element field of this same pop-up, make sure to replace LinearLayout with RelativeLayout. In the File name field we'll insert the exact same name as the file we just deleted: activity_main.xml. Then, we'll create a new layout file by right-clicking on the res/layout directory and selecting New > Layout resource file.Ī New Resource File pop-up with several fields should appear. (Since we're going to immediately create a new layout to replace the one we're deleting, this is okay.) A second pop-up will alert you that this layout is being used in other parts of the app. So, we'll need to revert this default Constraint layout back into its Relative cousin.ĭo you recall how to do this? We'll follow the same steps introduced in the previous lesson:įirst, we'll delete this automatically-created activity_main.xml file from the res/layout directory by right-clicking on its file and selecting Delete. However, as we discussed in the last lesson, we're going to practice working with Relative layouts first before exploring Constraint layouts on Wednesday night. This is a Constraint layout, in a special visual Constraint layout editor. If we open activity_main.xml, we can see a sort of visual editor depicting a layout similar to the one we saw when launching our emulator. As the filename specifies, layouts in Android are written in eXtensible Markup Language (XML) - that means no more CSS for us! Reverting to Relative Layout The activity_main.xml file is where we are going to style what the user sees and interacts with when they are viewing the welcome page of our app. We will learn about all of these resources over time. This folder will house all of our images, layout files, launcher icon, and string, color, and style values. The res folder contains all of the static resources that comprise our app. While in the Android project view, navigate to res/layout/activity_main.xml. Now that we successfully have our app up and running in the emulator, let’s get to work! First we are going to make a basic welcome page with a button that will eventually link to a page with a list of restaurants.
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