在Service中弹出Toast和Dialog

Posted 2022-12-03 Cloud_Castle

众所周知，Toast必须在UI主线程上才能正常显示，而在Service中是无法获得Acivity的Context的，在service中想显示出Toast只需将show的消息发送给主线程Looper就可以了

Handler handler = new Handler(Looper.getMainLooper());  
            handler.post(new Runnable()   
                public void run()   
                    Toast.makeText(getApplicationContext(), "存Service is runing!",  
                            Toast.LENGTH_SHORT).show();  
                  
            );  

此时便可显示Toast

Dialog的用法与此类似，但是要多加个权限

在manifest中添加此权限以弹出dialog

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

Builder builder = new AlertDialog.Builder(getApplicationContext())  
                    .setIcon(android.R.drawable.ic_dialog_info)  
                    .setTitle("service中弹出Dialog了")  
                    .setMessage("是否关闭dialog？")  
                    .setPositiveButton("确定",  
                            new DialogInterface.OnClickListener()   
                                public void onClick(DialogInterface dialog,  
                                        int whichButton)   
                                      
                                  
                            )  
                    .setNegativeButton("取消",  
                            new DialogInterface.OnClickListener()   
                                public void onClick(DialogInterface dialog,  
                                        int whichButton)   
  
                                  
                            );  
            final AlertDialog dialog = builder.create();  
            dialog.getWindow().setType(  
                    (WindowManager.LayoutParams.TYPE_SYSTEM_ALERT));  
            Handler handler = new Handler(Looper.getMainLooper());  
            handler.post(new Runnable()   
                public void run()   
                    dialog.show();  
                  
            );  

来自：http://blog.csdn.net/nmzkchina/article/details/15506373