Make the text box size flexible

Make the text box size flexible

To create a layout that's responsive to different screen sizes, you'll now make the text box stretch to fill all remaining horizontal space (after accounting for the button and margins).

Figure 8. Click to change the width and remove the right margin

Figure 9. The text box stretches to fill the remaining space
  1. Create a constraint from the right side of the button to the right side of the parent layout. This now defines the total width that the two views have available (which you can now fill with the text box).
  2. Add a constraint from the right side of the text box to the left side of the button. It might look like that's already there, but you're actually adding a bidirectional constraint between the two views. So both views are constrained to each other. This is called a chain (as indicated by the chain betwen the views), and it enables some extra layout options.
  3. Open the Properties window for the text box and then click the width indicator until set to Match Constraints, as indicated by callout 1 in figure 8. "Match constraints" means that the width is now determined by the horizontal constraints and margins. Therefore, the text box stretches to fill the horizontal space.
  4. However, the two views are separated by 32dp instead of 16dp, because both views have margins. So while still viewing the text box properties, change the right margin to 0, as indicated by callout 2 in figure 8.
Now the layout is done and should appear as shown in figure 9.
If it seems your layout did not turn out as expected, click below to see what your the XML should look like and compare it to what you see in the Text tab.

Run the app

If your app is already installed on the device from the previous lesson, simply click Apply Changes  in the toolbar to update the app with the new layout. Or click Run  to install and run the app.
The button still does nothing. To start another activity when the button is tapped, continue to the next lesson

Comments

Post a Comment

Popular posts from this blog

Change the UI strings

Image
Change the UI strings Click  Show Design   in the toolbar to preview the UI. Notice that the text input is pre-filled with "Name" and the button is labeled "Button." So now you'll change these strings. Open the  Project  window and then select  res > values > strings.xml . This is a string resources file where you should specify all your UI strings. Doing so allows you to manage all UI strings in a single location, which makes it easier to find, update, and localize (compared to hard-coding strings in your layout or app code). Click  Open editor  at the top of the editor window. This opens the Translations Editor, which provides a simple interface for adding and editing your default strings, and helps keep all your translated strings organized. Figure 7.  The dialog to add a new string Click  Add Key   to create a new string as the "hint text" for the text box. Enter "edit_message" for the key name. Enter "Enter a
Read more

Add Text box & Button

Image
Add a text box Figure 5.  The text box is constrained to the top and left of the parent layout First, you need to remove what's already in the layout. So click  TextView  in the  Component Tree  window, and then press Delete. From the  Palette  window on the left, click  Text  in the left pane, and then drag  Plain Text  into the design editor and drop it near the top of the layout. This is an  EditText  widget that accepts plain text input. Click the view in the design editor. You can now see the resizing handles on each corner (squares), and the constraint anchors on each side (circles). For better control, you might want to zoom in on the editor to 75% or higher using the buttons in the toolbar. Click-and-hold the anchor on the top side, and then drag it up until it snaps to the top of the layout and release. That's a constraint—it specifies the view should be 16dp from the top of the layout (because you set the default margins to 16dp). Similarly, create a c
Read more