Xiaomi smartphones today are equipped with displays with an aspect ratio that differs significantly from the classic formats of the past. Screens with cutouts, drop-shaped notch and even embedded cameras dictate new standards for displaying content. However, despite technological progress, many users face a situation where the interface of the phone book or incoming call does not occupy the entire available area of the matrix.
This can be uncomfortable, especially if you're used to seeing a large caller avatar or important call control buttons at maximum size.The problem is often not the hardware, but the software constraints or settings of the MIUI and HyperOS shell itself.The system can automatically restrict applications that are not optimized for the current display resolution.
In this article, we will look at all possible ways to force full-screen calls to be turned on, and we will touch on both standard interface settings and hidden engineering menus that allow you to fine-tune the behavior of the system when incoming connections.
Causes of black fields when calling
Before you start taking action, you need to understand the nature of the problem. Often users of Redmi and Poco notice that after updating the operating system or changing the theme of the design, the usual call interface is transformed. UI adaptability is a key term describing the ability of an application to adapt to different screen sizes. If the caller application believes that it is not optimized for your specific resolution, it can start in window mode or with black fields on the sides.
Third-party themes downloaded from MIUI Themes store may contain graphic elements that do not stretch to the full screen, but have a fixed resolution, in which case the system call will be displayed within the framework set by the author of the theme, ignoring the physical boundaries of your display.
Also, consider the specifics of individual calling apps, and if you use third-party solutions like Truecaller or enterprise clients, they may have their own zoom settings that prioritize system-based ones.
⚠️ Note: Using modified system files to change the call interface can cause the phone to run unstable.Before making profound changes, back up your data.
In some cases, black fields are not a bug, but a design feature that the manufacturer has implemented to preserve the proportions of the interface on different models, but more often than not, this is a rectifying limitation that can be circumvented through the developer menu or special codes.
Basic setup of full-screen mode
The first and safest step is to check the standard display settings. In the MIUI and HyperOS shells, there is a global parameter that regulates the behavior of applications on screens with cutouts. To access it, go to the Settings menu, then select the Screen (or additionally depending on the OS version).
In the list that opens, you'll see all the apps installed. Find your calling app (usually called "Phone" or has a Google/MIUI logo) on the list and select "Full Screen" or "Hide the Notch" option, which will force the application interface to stretch across the entire matrix area, ignoring the reserved areas.
☑️ Checking screen settings
If you don't find a standard call in the app list, try switching to displaying all the apps, not just the ones that use the cutout. Sometimes the system hides apps that it thinks are already working correctly, but the visual bug is still present.
When you change your settings, be sure to restart your device, and reboot is necessary to ensure that the system services responsible for rendering the interface apply new zoom parameters. Without restarting, the changes may only take effect after the next incoming call or not apply at all.
Configure through the engineering menu and codes
For more advanced users, you can access hidden settings through the engineering menu, which is a powerful tool that allows you to control modem and interface settings at a low level. To enter the menu, open the Phone app and type the combination ##6484##. This command activates the CIT hardware testing mode.
However, the way you set up the call display is more often a different route, depending on your device's processor (Snapdragon or MediaTek). Try entering the code ##4636#. If the menu opens, go to Phone Information, where you can find parameters related to network type and preferences, which indirectly affects the call interface in some firmware.
A more specific code for resetting interface settings is ##8558##. It opens Portable Test Mode. Here you can try to find the option to reset UI settings or switch interface versions, if any are available for your model. Be careful: changing unknown parameters in the engineering menu can lead to resetting network settings.
⚠️ Attention: The engineering menu is for the professionals, do not change the values of the parameters, the purpose of which you are not 100% sure, so as not to disrupt the operation of the radio module.
There is also code ##3646633## (relevant to MediaTek processors) that opens a deep engineering menu, and you can find the Hardware Testing -> Display section, which sometimes has resolution and orientation settings, but this is rare for custom scripts.
Application compatibility modes
Newer versions of Android, which run Xiaomi 13, 14, 15 and older models, have a compatibility mode mechanism that allows you to force applications to run in a certain format.
Go to Settings -> About the phone. Find the line "Version." MIUI» or "Version" OS» And press it fast. 7-10 once in a row, until the notification "You became a developer" appears. After that, go back to the main settings menu, go to Additional -> For developers.
In the developer menu, scroll down to the Apps section. Find App Compatibility Modes. In the list, find the Phone or Contacts app. Activate the switch for that application. The system will suggest restarting it or the device.
This method is especially effective if the problem occurred after the Android update from version 11 to 12, 13 or 14.Old interface components may conflict with the new rules of rendering, and compatibility mode eliminates this conflict, forcing the system to apply old, proven zoom rules.
| Method of decision | Difficulty | Risk of error | Efficiency |
|---|---|---|---|
| Screen settings (Netching) | Low. | Absent. | Tall. |
| Replacement of the topic with standard | Low. | Absent. | Medium |
| Developer mode | Medium | Low. | Tall. |
| Engineering menu | Tall. | Medium. | Depends on the model. |
As you can see from the table, the safest and most effective method is to work with standard cutout settings, and the engineering menu should be used only in extreme cases when other methods have not worked.
The Impact of Themes and Third-Party Launchers
Often, theme is the cause of incorrect display. Even if you did not change the topic consciously, the system update could “fly” to a default, but with residual files from the previous one, or vice versa, apply a theme with a bug. To rule out this factor, go to the Topic app.
In your user profile, select the "Themes" section and apply the standard "Classic" or "Default" theme. Once you apply the theme, the system will redraw all interfaces, including the lock screen and the call screen. If the problem was in the theme graphic, it will disappear instantly.
What if the standard theme doesn’t help?
Third-party launchers, such as Nova Launcher or Microsoft Launcher, usually do not affect the incoming call screen, as this is a system window. However, if you use modified versions of root launchers, they can intercept system calls, in which case try temporarily disabling the launcher and returning to the standard Poco Launcher or MIUI Launcher desktop.
It’s also worth checking whether the “Enlarged Font” or “Enlarged Interface” mode is enabled in special features, which can distort the layout of the call screen, shifting buttons and creating the illusion of a partial screen.
Alternative Calling Applications
If Xiaomi or Google’s Phone system app stubbornly doesn’t want to be displayed on the full screen, it makes sense to consider alternatives: Google Play has a lot of quality calls that fully support modern full-screen display standards.
One of the best options is Truecaller. This app not only defines numbers, but also has flexible theme and interface settings. In Truecaller's settings, you can select "Full Screen Mode" and customize the look of the call card. Once you install and assign the application to the default call, it will replace the standard interface.
Another popular option is Simple Dialer (from the Simple Mobile Tools suite), an open-source application that is minimalist and fully adaptable to any screen, including foldable smartphones and devices with unusual proportions.
⚠️ Warning: When installing a third-party call, be sure to provide it with all the necessary permissions (contacts, call log, microphone), otherwise it will not be able to function correctly.
To install an alternative app, download it, launch it, and follow the instructions on the screen. Android will prompt you to choose the new default app for making calls. Confirm the choice, and the new interface will replace the old one.
Resetting and radical measures
When software failures accumulate, you may need to reset your phone app settings, which will not delete your contacts (as they are stored in your Google account or on your phone). SIM-map), but will return the call settings to factory state -> Annexes -> All applications.
Find the phone list (maybe two from Google and MIUI, reset the one you're using). Click Clear -> Clear everything (or Reset settings) and then check if the screen problem has been resolved.
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Before resetting your settings, make sure your contacts are synced with your Google account. Open the Contacts app, go to the settings and click Sync Now.
If nothing works, the last option is a full reset of the device (Hard Reset), which is an extreme measure that will delete all data. Before you do this, make sure to make a full backup to the cloud service or computer. After resetting and clean installation without restoring the old settings through the Mi Cloud (to avoid returning the bug), the problem should disappear.
In rare cases, the problem can be hardware, such as a defect in the display plume or controller that incorrectly determines the resolution of the matrix. If full-screen mode does not work anywhere (either in games, videos, or calls), you should contact an authorized service center.