我使用悬浮窗权限在我的应用程序中显示某些信息。在API 23-25上运行时，它可以正常工作（根据Unable to add window android.view.ViewRoot$W@44da9bc0 -- permission denied for this window type的要求进行请求和授权等操作)。 （非常感谢ceph3us！）
但是，在API 26上尝试同样的操作时出现错误，基本上是在调用时出现“窗口类型2002的权限被拒绝”。
windowManager.addView(frameLayout, params);
谷歌改变了覆盖层的工作方式吗？有什么想法，如何在Android 8（奥利奥）API 26中将我的文本作为覆盖层叠加到屏幕上？ 谢谢您的建议！
这是错误日志：
08-24 16:41:56.730 2615-2615/net.zwittscha.testoverlay E/AndroidRuntime: FATAL EXCEPTION: main
Process: net.zwittscha.testoverlay, PID: 2615
java.lang.RuntimeException: Unable to start activity ComponentInfo{net.zwittscha.testoverlay/net.zwittscha.testoverlay.MainActivity}:
android.view.WindowManager$BadTokenException: Unable to add window android.view.ViewRootImpl$W@6fa0089 --
permission denied for window type 2002
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: android.view.WindowManager$BadTokenException:
Unable to add window android.view.ViewRootImpl$W@6fa0089 --
permission denied for window type 2002
at android.view.ViewRootImpl.setView(ViewRootImpl.java:789)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:356)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:92)
at net.zwittscha.testoverlay.MainActivity.createOnTopView(MainActivity.java:46)
at net.zwittscha.testoverlay.MainActivity.checkDrawOverlayPermission(MainActivity.java:66)
at net.zwittscha.testoverlay.MainActivity.onCreate(MainActivity.java:28)
at android.app.Activity.performCreate(Activity.java:6975)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
在我的 Manifest 文件中，我有：
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
<uses-permission android:name="android.permission.ACTION_MANAGE_OVERLAY_PERMISSION"/>
这是我的 MainActivity:
public class MainActivity extends AppCompatActivity {
DrawView dv;
FrameLayout frameLayout;
WindowManager windowManager;
LayoutInflater layoutInflater;
/** code to post/handler request for permission */
public final static int REQUEST_CODE = 1234;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
checkDrawOverlayPermission();
}
public void createOnTopView() {
WindowManager.LayoutParams params = new WindowManager.LayoutParams(
WindowManager.LayoutParams.WRAP_CONTENT,
WindowManager.LayoutParams.WRAP_CONTENT,
WindowManager.LayoutParams.TYPE_PHONE,
WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE,
PixelFormat.TRANSLUCENT);
params.gravity = Gravity.CENTER;
if (frameLayout == null) frameLayout = new FrameLayout(getApplicationContext());
if (dv == null) dv = new DrawView(getApplicationContext());
windowManager = (WindowManager)
getApplicationContext().getSystemService(Context.WINDOW_SERVICE);
windowManager.addView(frameLayout, params);
windowManager.addView(dv, params);
layoutInflater = (LayoutInflater)
getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// Here is the place where you can inject whatever layout you want.
layoutInflater.inflate(R.layout.activity_main, frameLayout);
}
public void checkDrawOverlayPermission() {
/* check if we already have permission to draw over other apps */
if (android.os.Build.VERSION.SDK_INT > 22) {
if (!Settings.canDrawOverlays(this)) {
/* if not construct intent to request permission */
Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
Uri.parse("package:" + getPackageName()));
/* request permission via start activity for result */
startActivityForResult(intent, REQUEST_CODE);
}
else {
createOnTopView();
}
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
/* check if received result code
is equal our requested code for draw permission */
if (requestCode == REQUEST_CODE && android.os.Build.VERSION.SDK_INT > 22) {
/* if so check once again if we have permission */
if (Settings.canDrawOverlays(this)) {
createOnTopView();
}
}
}
}
这是DrawView:
public class DrawView extends View {
int w;
int h;
int r;
float screenFactor;
TextPaint startTextPaint;
public DrawView(Context activity) {
super(activity);
}
@Override
protected void onSizeChanged(int width, int height, int oldw, int oldh) {
w = width;
h = height;
r = w / 2;
screenFactor = (r / 160f);
if (startTextPaint == null) startTextPaint = new TextPaint();
startTextPaint.setTextSize(100);
startTextPaint.setTextAlign(Paint.Align.CENTER);
startTextPaint.setTypeface(Typeface.create("Roboto Condensed", Typeface.BOLD));
super.onSizeChanged(w, h, oldw, oldh);
}
@Override
protected void onDraw(Canvas canvas) {
startTextPaint.setARGB(255,255,0,0);
canvas.drawText("Test", w / 2, h / 2, startTextPaint);
}
}