Intent

Intent分为显示和隐式intent；

显示intent：commponent+extra

隐式intent：Action+Data(uri、mimetype)+category

下面是隐式intent代码示例

button.Click+=delegate{

Intent intent=new Intent();

intent.SetAction(Intent.ActionDial);

//拨电话，前提需要设置应用程序Call权限

Android.Net.Uri uriTel=Android.Net.Uri.Parse("tel:110");

intent.SetData(uriTel);

/*

//启动一个应用

intent.SetAction(Intent.ActionMain);

//启动浏览器

intent.AddCategory(Intent.CategoryAppBrowser);

//回到桌面

intent.AddCategory(Intent.CateogroyHome);;

*/

StartAcitivity(intent);

}

自定义可以通过隐式intent启动的在activity

[IntentFilter(new string[]{"com.itlead.action1"},

                          Categories=new string[]{"com.itlead.category1",intent.CategoryDefault})]

//Intent启动

intent.AddAction("com.itlead.action1"});

intent.AddCategory(“com.itlead.category1");

还可以访问其他应用的action，只要知道相应的action

Android.Net.Uri fileUri=Android.Net.Uri.Parse("file:///mnt/sdcard/ttt.mp3");

//设定Mimetype

intent.SetAction(Intent.ActionView);

intent.SetDataAndType(fileUri,"audio/mpeg");

读取SDCard权限

Mount_UNMOUNT_FILESYSTEMS

WRITE_EXTERNAL_STORAGE

intent.SetAction(Android.Provider.MediaStore.ActionImageCapture);

Java.IO.File sdPath=Android.OS.Environment.ExternalStorageDirectory;

Java.IO.File imagefile=new Java.IO.File(sdPath.AbsolutePath,"1.jpeg");

  imguri=Android.Net.Uri.FromFile(imagefile);

intent.PutExtra(Android.Provider.MediaStore.ExtraOutput,imguri);

StartActivityForResult(intent,2);

Android.Net.Uri imguri;

protected override void OnActivityResult(int requestCode,[GeneratedEnum] Result resoult)

{

   if(requestCode==2 && result==Result.Ok)

  {

            ImageView iv=FindViewById<ImageView>(Resource.Id.imageView1);

                  iv.SetImageURI(imguri);

  }

base.OnactivityResult(requestCode,result,data);

}