安卓多屏异显_vendor.display.builtin_presentation=1

有些定制化的安卓板，有时候往往不止一个显示屏，从安卓4.2开始就有多屏的概念。

1.获取当前系统所有屏幕信息：

        val displayManager = getSystemService(Context.DISPLAY_SERVICE) as DisplayManager
        val displays: Array<Display> = displayManager.displays
        //获取屏幕个数
        val screenCount: Int = displays.size
        Log.e("TAG", "screenCount======${screenCount}")
        //循环获取所有屏幕信息
        for (display in displays) {
            val displayId = display.displayId
            val displayName = display.name
            val displayWidth = display.width
            val displayHeight = display.height
            Log.e("TAG", "displayId======${displayId}")
            Log.e("TAG", "displayName======${displayName}")
            Log.e("TAG", "displayWidth======${displayWidth}")
            Log.e("TAG", "displayHeight======${displayHeight}")
        }

 2.关于多屏，需要引进一个叫做 Presentation的东西， Presentation 是扩展自 dialog.相当于一个升级版的弹窗，其实还是在同一个activity里面完成的，两个屏幕里面的内容，可以通过同一个activity进行控制和相关数据变动展示。在副屏上显示不同内容。它的显示内容是依附在主屏的Activity上的，如果Activity被销毁Presentation也不会再显示，多屏也是支持的，接下来看我怎么操作多屏。

比如我有三个屏：分别为一个主屏以及两个副屏，先创建两个Presentation

package com.example.test;
 
import android.app.Presentation;
import android.content.Context;
import android.os.Build;
import android.os.Bundle;
import android.view.Display;
 
import androidx.annotation.RequiresApi;
 
@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR1)
public class BuiltInPresentation extends Presentation {
 
 
    public BuiltInPresentation(Context outerContext, Display display) {
        super(outerContext, display);
    }
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
 
        // 设置内置屏幕的布局和内容
        setContentView(R.layout.disactivity);
    }
}

package com.example.test;
 
import android.app.Presentation;
import android.content.Context;
import android.media.MediaPlayer;
import android.os.Build;
import android.os.Bundle;
import android.view.Display;
import android.widget.VideoView;
 
import androidx.annotation.RequiresApi;
 
@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR1)
public class BuiltInPresentation2 extends Presentation {
 
    public BuiltInPresentation2(Context outerContext, Display display) {
        super(outerContext, display);
    }
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
 
        // 设置内置屏幕的布局和内容
        setContentView(R.layout.disactivity2);
    }
}

 3.我们继续看主Activity

package com.example.test
 
import android.annotation.SuppressLint
import android.content.Context
import android.hardware.display.DisplayManager
import android.os.Build
import android.os.Bundle
import android.util.Log
import android.view.Display
import android.widget.SeekBar
import androidx.annotation.RequiresApi
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.activity_main.*
import java.util.*
 
 
class MainActivity : AppCompatActivity() {
 
    private var builtInPresentation: BuiltInPresentation? = null
    private var builtInPresentation2: BuiltInPresentation2? = null
 
    @RequiresApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
 
        setContentView(R.layout.activity_main)
 
        val displayManager =
            getSystemService(Context.DISPLAY_SERVICE) as DisplayManager
        val displays: Array<Display> = displayManager.displays
        for (display in displays) {
            val displayId = display.displayId
            val displayName = display.name
            val displayWidth = display.width
            val displayHeight = display.height
            Log.e("TAG", "displayId======${displayId}")
            Log.e("TAG", "displayName======${displayName}")
            Log.e("TAG", "displayWidth======${displayWidth}")
            Log.e("TAG", "displayHeight======${displayHeight}")
            val screenCount: Int = displays.size
            Log.e("TAG", "screenCount======${screenCount}")
        }
 
 
        
        builtInPresentation = BuiltInPresentation(this, displays[1])
        builtInPresentation!!.show()
 
 
 
        builtInPresentation2 = BuiltInPresentation2(this, displays[2])
        builtInPresentation2!!.show()
    }
 
    override fun onDestroy() {
        super.onDestroy()
        // 在Activity销毁时，确保隐藏和释放Presentation
        if (builtInPresentation != null) {
            builtInPresentation!!.dismiss()
            builtInPresentation = null
        }
 
        if (builtInPresentation2 != null) {
            builtInPresentation2!!.dismiss()
            builtInPresentation2 = null
        }
    }
}

 到这里，你们大概应该都看懂了，我直接在主activity里面调用两个Presentation类，传入不同的屏信息，设置不同的屏内容。这里需要注意你的主屏是第几个，否则有可能不生效！一般的主屏都是displays[0],就是主activity显示的界面。