原因

<!-- 在应用程序的AndroidManifest.xml文件中添加权限 -->
 <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

在某些机型上居然后出现permission denied for window type 2038错误：

E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.lanmao.jpsg.android, PID: 27024
android.view.WindowManager$BadTokenException: Unable to add window android.view.ViewRootImpl$W @ff8b1a 
    -- permission denied for window type 2038
    at android.view.ViewRootImpl.setView(ViewRootImpl.java:1090)
    at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:381)
    at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:93)
    at com.quicksdk.apiadapter.undefined.a.y.b(ToolBar.java:58)
    at com.quicksdk.apiadapter.undefined.UserAdapter$6.onClick(UserAdapter.java:138)
    at com.quicksdk.apiadapter.undefined.a.r$a$1.onClick(LoginDialog.java:88)
    at android.view.View.performClick(View.java:7339)
    at android.widget.TextView.performClick(TextView.java:14226)
    at android.view.View.performClickInternal(View.java:7305)
    at android.view.View.access$3200(View.java:846)
    at android.view.View$PerformClick.run(View.java:27787)
    at android.os.Handler.handleCallback(Handler.java:873)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:214)
    at android.app.ActivityThread.main(ActivityThread.java:7081)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:494)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:965) ```

Build.VERSION.SDK_INT

Build.VERSION.SDK_INT 软件app安装在哪个手机上，该手机的操作系统版本号 比如8.1对应的SDK_INT是27

The SDK version of the software currently running on this hardware device.
This value never changes while a device is booted, but it may increase when
the hardware manufacturer provides an OTA update.

Android API与Android版本对应关系

SDK_INT

解决方案

主要代码

    private static final int FloatRequestCode = 1002;
    public void onCreate() {
        super.onCreate();
        Activity context =  getContext();
        com.quicksdk.Sdk.getInstance().onCreate(context);
        if(!checkFloatPermission(context)){
            requestFloatPermission(context, FloatRequestCode);
        }
      }

    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        final Activity context = getContext();
        com.quicksdk.Sdk.getInstance().onActivityResult(context,
                requestCode, resultCode, data);
        if(requestCode == FloatRequestCode) {
            Handler handler = new Handler();
            handler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    if(!checkFloatPermission(context)){
                        requestFloatPermission(context,FloatRequestCode);
                    }
                }
            },1000);
        }
    }
    /***
     * 检查悬浮窗开启权限
     * @param context
     * @return
     */
    public boolean checkFloatPermission(Context context) {
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT)
            return true;
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
            try {
                Class cls = Class.forName("android.content.Context");
                Field declaredField = cls.getDeclaredField("APP_OPS_SERVICE");
                declaredField.setAccessible(true);
                Object obj = declaredField.get(cls);
                if (!(obj instanceof String)) {
                    return false;
                }
                String str2 = (String) obj;
                obj = cls.getMethod("getSystemService", String.class).invoke(context, str2);
                cls = Class.forName("android.app.AppOpsManager");
                Field declaredField2 = cls.getDeclaredField("MODE_ALLOWED");
                declaredField2.setAccessible(true);
                Method checkOp = cls.getMethod("checkOp", Integer.TYPE, Integer.TYPE, String.class);
                int result = (Integer) checkOp.invoke(obj, 24, Binder.getCallingUid(), context.getPackageName());
                return result == declaredField2.getInt(cls);
            } catch (Exception e) {
                return false;
            }
        } else {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                AppOpsManager appOpsMgr = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
                if (appOpsMgr == null)
                    return false;
                int mode = appOpsMgr.checkOpNoThrow("android:system_alert_window", android.os.Process.myUid(), context
                        .getPackageName());
                return Settings.canDrawOverlays(context) || mode == AppOpsManager.MODE_ALLOWED || mode == AppOpsManager.MODE_IGNORED;
            } else {
                return Settings.canDrawOverlays(context);
            }
        }
    }

    /**
     * 悬浮窗开启权限
     * @param context
     * @param requestCode
     */
    public void requestFloatPermission(Activity context, int requestCode){
        Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION);
        intent.setData(Uri.parse("package:" + context.getPackageName()));
        context.startActivityForResult(intent, requestCode);
    }

参考

• Android中代码动态判断是否开启悬浮窗权限和申请悬浮窗权限
• Android悬浮窗权限“android.permission.SYSTEM_ALERT_WINDOW”判断是否开启问题
• Android M 小米手机 Settings.canDrawOverlays（悬浮窗权限：SYSTEM_ALERT_WINDOW）一直返回false的问题
• Android 悬浮窗及权限
• FloatWindow 安卓任意界面悬浮窗