判断资源存在与否如判断一个drawable的图片存在及通过id加载图片

留下来以后备用！

int i= getResources().getIdentifier("icon", "drawable", getPackageName()) ;
 if(i>0)
 {Log.i("aa","aa");}
 else
 {Log.i("vbv","aa");}或者
int resID = getResources().getIdentifier("org.loveandroid.androidtest:drawable/gallery_photo_1",null,null);
 
int resID = getResources
 (
 ).
 getIdentifier
 (
 "org.anddev.android.testproject:drawable/bug", 
 null, 
 null
 ); 
 
// or 
 
int resID = getResources
 (
 ).
 getIdentifier
 (
 "bug", 
 "drawable", 
 "org.anddev.android.testproject"
 );

第一个参数其实

full_package:type/filename_without_ending是这种格式 然后其他的可以为null

Java代码 ​​

int idFlag = getResources().getIdentifier(   
      getPackageName() + ":drawable/flag",    
      null, null);   
// 或是   
int idFlag = getResources().getIdentifier(   
      "flag", "drawable", getPackageName());

Java代码 ​​

var Drawable[] dw = new Drawable[10];   
  
for (int i = 1; i <= 10; i++) {   
  int id = getResources().getIdentifier(   
                    "flag" + i,    
                    "drawable", getPackageName());   
  dw[i-1] = getResources().getDrawable(id);   
}

Java代码 ​​ ​​​ ​​​

private void    
  _DumpAllResourceIDs(Class<?> classType)    
    throws IllegalArgumentException {   
  Field[] fIDs = classType.getFields();   
           
  try {   
    for (int i = 0; i < fIDs.length; i++) {   
      Field fld = fIDs[i];   
      int nID = fld.getInt(null);   
      Log.d("dbg",   
        classType.getSimpleName() + " " +    
        i + ": " +    
        fld.getName() + "=" +   
        nID);   
    }   
  } catch (Exception e) {   
    throw new IllegalArgumentException();   
  }   
}

Java代码 ​​ ​​​ ​​​

import java.lang.reflect.Field;   
...   
  _DumpAllResourceIDs(R.layout.class);   
  _DumpAllResourceIDs(R.drawable.class);

Java代码 ​​ ​​​ ​​​ ​​

1. R$layout 0: main=2130903040
2. R$layout 1: small_spinner_dropdown_item=2130903041
3. R$drawable 0: icon=2130837504