在我的Android应用程序中,我有下面一段查找联系人ID的代码,我刚刚将目标从1.5更改为2.2,但minsdk为3(1.5),因此我可以在2.2中使用ContactsContract Uri,在1.5中使用People Uri。
  
  
   但是,在1.5设备上运行时,该代码会导致以下错误:
  
  07-27 15:02:53.382: WARN/dalvikvm(12656): VFY: unable to resolve static field 25 (CONTENT_URI) in Landroid/provider/ContactsContract$Contacts;
  
  
  
  
   我已经看到了如何使用反射来使用多个/不同版本的方法的示例,但是在我想使用ContactsContract Uri的mycase中如何使用它呢?
  
  
   这是我的密码:
  
  
  findViewById(R.id.contactimage).setOnClickListener(new OnClickListener() {
                public void onClick(View v) {
                    String sdk = android.os.Build.VERSION.SDK;
                    Uri contactUri;
                    Log.d("CDA", "Contact ID Button pressed = " + contactId);
                    if(sdk.equals("8")){
                        contactUri = ContentUris.withAppendedId
                        (ContactsContract.Contacts.CONTENT_URI, contactId);
                        Intent intent = new Intent(Intent.ACTION_VIEW, contactUri);
                        startActivity(intent);
                    }
                    else{
                    contactUri = ContentUris.withAppendedId
                    (People.CONTENT_URI, contactId);
                    Intent intent = new Intent(Intent.ACTION_VIEW, contactUri);
                    startActivity(intent);
                    }
                    dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_DOWN,KeyEvent.FLAG_SOFT_KEYBOARD));
                    dispatchKeyEvent(new KeyEvent(KeyEvent.ACTION_UP, KeyEvent.KEYCODE_BACK));
                }
        });
  
  
   编辑:
  
  
   下面是一个如何完成的示例:
  
  private static Uri CONTENT_URI=null;
private static String NAME_URI=null;
private static String ID_URI=null;
private static String NUMBER_URI = null;
private static Uri PHONE_LOOKUP = null;
static int sdk;
 static {
     sdk=new Integer(Build.VERSION.SDK).intValue();
     if (sdk>=5) {
     try {
     Class clazz=Class.forName("android.provider.ContactsContract$CommonDataKinds$Phone");
     Class clazz_phonelookup=Class.forName("android.provider.ContactsContract$PhoneLookup");
     NAME_URI=(String)clazz.getField("DISPLAY_NAME").get(clazz);
     ID_URI=(String)clazz.getField("_ID").get(clazz);
     NUMBER_URI=(String)clazz.getField("NUMBER").get(clazz);
     PHONE_LOOKUP =(Uri)clazz_phonelookup.getField("CONTENT_FILTER_URI").get(clazz);
     }
     catch (Throwable t) {
     Log.e("reflection", "Exception when determining CONTENT_URI", t);
     }
     }
     else {
     CONTENT_URI=Contacts.People.CONTENT_URI;
     NAME_URI=People.NAME;
     ID_URI=People._ID;
     NUMBER_URI=People.NUMBER;
     PHONE_LOOKUP = null;
     }
     }