从服务显示警报对话框时获取异常 - 无法添加窗口 - 令牌null不适用于应用程序

Question

从Service显示Alert Dialog时获取Exception.

以下是我的Service类中的代码:我正在尝试显示AlertDialog.

但我收到错误:无法添加窗口 - 令牌null不适用于应用程序

我还将我的日志快照附加到此问题.

 if(!mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)&& !mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)){

                Log.d("TrackingService","H: Exception after this");

                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setMessage("Your GPS seems to be disabled, do you want to enable it?")
                .setCancelable(false)
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    public void onClick(final DialogInterface dialog, final int id) {
                        startActivity(new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS));
                    }
                })
                .setNegativeButton("No", new DialogInterface.OnClickListener() {
                    public void onClick(final DialogInterface dialog,  final int id) {
                        dialog.cancel();
                    }
                });
                AlertDialog alert = builder.create();
                alert.show();
            }

Answer 1

我有这个问题,但现在solved,如果你想真正从服务运行alertDialog,你应该配置对话框,系统警报,并记得在AndroidManifest.xml中添加权限:

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

/这是示例代码:

AlertDialog.Builder builder = new AlertDialog.Builder(ctx);
builder.setTitle("Test dialog");
builder.setIcon(R.drawable.icon);
builder.setMessage("Content");
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {
        //Do something
        dialog.dismiss();
   }
});
builder.setNegativeButton("Close", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {
        dialog.dismiss();
    }
});
AlertDialog alert = builder.create();
alert.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
alert.show();