Presentation solution with autosize support.

SecondaryDisplayHelper.java

import android.content.Context;
import android.content.Intent;
import android.media.MediaRouter;
import android.os.Build;
import android.provider.Settings;
import android.util.DisplayMetrics;
import android.view.ContextThemeWrapper;
import android.view.Display;
import android.view.View;
import android.view.WindowManager;
import android.widget.Toast;

import androidx.annotation.MainThread;
import androidx.annotation.StyleRes;

import me.jessyan.autosize.AutoSizeCompat;

/**
 * Created by <a href="mailto:xzx8023@outlook.com">Vixb</a> on 2022/8/7.
 */
public class SecondaryDisplayHelper {
    private WindowManager windowManager;
    private View view;
    private boolean isAdd;

    public SecondaryDisplayHelper(Context context, @StyleRes int themeResId, float designWidthInDp, ViewCreator viewCreator) {
        MediaRouter router = (MediaRouter) context.getSystemService(Context.MEDIA_ROUTER_SERVICE);
        MediaRouter.RouteInfo routeInfo = router.getSelectedRoute(MediaRouter.ROUTE_TYPE_LIVE_AUDIO
                | MediaRouter.ROUTE_TYPE_LIVE_VIDEO
                | MediaRouter.ROUTE_TYPE_USER);
        if (routeInfo != null) {
            Display display = routeInfo.getPresentationDisplay();
            if (display != null) {
                Context secondaryContext = new ContextThemeWrapper(context.createDisplayContext(display), themeResId);
                AutoSizeCompat.autoConvertDensityBaseOnWidth(
                        secondaryContext.getResources(),
                        designWidthInDp * screenSize(context) / screenSize(secondaryContext)
                );
                windowManager = (WindowManager) secondaryContext.getSystemService(Context.WINDOW_SERVICE);
                view = viewCreator.callback(secondaryContext);
            }
        }
    }

    @MainThread
    void show() {
        if (windowManager != null && view != null && !isAdd) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                Context context = view.getContext();
                if (!Settings.canDrawOverlays(context)) {
                    context.startActivity(new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION));
                    Toast.makeText(context, "请允许该应用显示在其他应用的上层", Toast.LENGTH_SHORT).show();
                } else {
                    windowManager.addView(view, new WindowManager.LayoutParams(getWindowType()));
                    isAdd = true;
                }
            } else {
                windowManager.addView(view, new WindowManager.LayoutParams(getWindowType()));
                isAdd = true;
            }
        }
    }

    @MainThread
    void dismiss() {
        if (windowManager != null && view != null && isAdd) {
            isAdd = false;
            windowManager.removeView(view);
        }
    }

    interface ViewCreator {
        View callback(Context context);
    }

    private float screenSize(Context context) {
        DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();
        return (float) Math.sqrt(displayMetrics.widthPixels * displayMetrics.widthPixels
                + displayMetrics.heightPixels * displayMetrics.heightPixels);
    }

    private int getWindowType() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            return WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
        } else {
            return WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
        }
    }
}

SecondaryDisplayHelper.kt

import android.content.Context
import android.content.Intent
import android.media.MediaRouter
import android.os.Build
import android.provider.Settings
import android.view.ContextThemeWrapper
import android.view.View
import android.view.WindowManager
import android.widget.Toast
import androidx.annotation.MainThread
import androidx.annotation.StyleRes
import me.jessyan.autosize.AutoSizeCompat
import kotlin.math.pow
import kotlin.math.sqrt

/**
 * Created by [Vixb](mailto:xzx8023@outlook.com) on 2022/8/7
 */
class SecondaryDisplayHelper(
    ctx: Context,
    @StyleRes themeResId: Int,
    designWidthInDp: Float,
    block: Context.() -> View
) {
    private lateinit var windowManager: WindowManager
    private lateinit var view: View
    private var isAdd = false

    init {
        ctx.apply {
            (getSystemService(Context.MEDIA_ROUTER_SERVICE) as MediaRouter).getSelectedRoute(
                MediaRouter.ROUTE_TYPE_LIVE_AUDIO
                        or MediaRouter.ROUTE_TYPE_LIVE_VIDEO
                        or MediaRouter.ROUTE_TYPE_USER
            )?.presentationDisplay?.run {
                ContextThemeWrapper(
                    createDisplayContext(this),
                    themeResId
                ).also { secondaryContext ->
                    AutoSizeCompat.autoConvertDensityBaseOnWidth(
                        secondaryContext.resources,
                        designWidthInDp * screenSize() / secondaryContext.screenSize()
                    )
                    this@SecondaryDisplayHelper.windowManager =
                        secondaryContext.getSystemService(Context.WINDOW_SERVICE) as WindowManager
                    this@SecondaryDisplayHelper.view = block(secondaryContext)
                }
            }
        }
    }

    @MainThread
    fun show() {
        if (::windowManager.isInitialized && ::view.isInitialized && !isAdd) {
            isAdd = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
                if (!Settings.canDrawOverlays(view.context)) {
                    view.context.startActivity(Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION))
                    Toast.makeText(view.context, "请允许该应用显示在其他应用的上层", Toast.LENGTH_SHORT).show()
                    return
                } else {
                    windowManager.addView(view, WindowManager.LayoutParams(getWindowType()))
                    true
                }
            else {
                windowManager.addView(view, WindowManager.LayoutParams(getWindowType()))
                true
            }
        }
    }

    @MainThread
    fun dismiss() {
        if (::windowManager.isInitialized && ::view.isInitialized && isAdd) {
            isAdd = false
            windowManager.removeView(view)
        }
    }

    private fun getWindowType() =
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY
        } else {
            WindowManager.LayoutParams.TYPE_SYSTEM_ALERT
        }

    private fun Context.screenSize() = resources.displayMetrics.run {
        sqrt(
            widthPixels.toFloat().pow(2) +
                    heightPixels.toFloat().pow(2)
        )
    }
}

老师 这个有没有使用示例