If it is not a battery problem, it can be determined that it is a system problem. You can press and hold the power button+volume down button to enter the recovery mode when the machine is turned off, and select Erase Date/Restore Factory Settings to clear the data and restore the factory settings.
1. In the final analysis, the memory occupation of Android phone is too high, which leads to the occupation of other applications when making calls, leading to the problem of black screen. We can solve this problem by cleaning up the memory. You can quickly clean up the memory through the one-click cleaning function of protection software such as 360 Mobile Guardian and Tencent Mobile Manager.
2. Brush machine: Systems that can brush machines, such as Android 4.0, have more performance in touch delay. Therefore, it is suggested that all Android phones should be brushed above 4. 1, which was unimaginable in the past with 4.0 or even 2.3 systems. You can brush some pure rom systems to reduce the occupation of memory by software.
3. Close: This setting has been set since android 4.0. Android 4.0 has two settings about this setting, including window animation scaling and transition animation scaling, which are set in "Sender Options" in "System Settings". Of course, you can close other files that may consume a lot of memory.
4. Uninstalling system programs: Now more and more official systems come with many annoying programs that cannot be uninstalled. These softwares often start by themselves, which has a great influence on the system fluency. However, to delete these self-contained software, you need to obtain root permission. After getting root permission, you can use Tencent Mobile Manager and 360 Mobile Guardian to uninstall the system program and reserve more memory space.
5. Delete the startup item: closing the startup item and the software background item can effectively improve the fluency of the mobile phone and solve the phenomenon of mobile phone jamming. We can use third-party programs, such as Rio Tinto Toolbox, 360 Mobile Guardian, 360 Optimization Master and other software to prohibit boot startup items and background self-startup items.
6. Sometimes, Android phones have distance sensing. When the phone is in a call, the screen close to the ear will turn off, which is a normal reaction. You can also change the mobile phone dialing program, or reuse the third-party dialing software such as Android dialing software and qq address book.