Question

我无法从Gdx图书馆进入Android的外部储藏室

简化代码 :

import android.app.Activity;
import android.os.Bundle;
import com.badlogic.gdx.Gdx;

public class Mp3AndFftTest extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Gdx.files.isExternalStorageAvailable();
    }
}

造成这种情况的原因:

ERROR   AndroidRuntime  FATAL EXCEPTION: main
ERROR   AndroidRuntime  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cmbryan.android/com.cmbryan.android.Mp3AndFftTest}: java.lang.NullPointerException
ERROR   AndroidRuntime      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
ERROR   AndroidRuntime      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
ERROR   AndroidRuntime      at android.app.ActivityThread.access$1500(ActivityThread.java:117)
ERROR   AndroidRuntime      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
ERROR   AndroidRuntime      at android.os.Handler.dispatchMessage(Handler.java:99)
ERROR   AndroidRuntime      at android.os.Looper.loop(Looper.java:123)
ERROR   AndroidRuntime      at android.app.ActivityThread.main(ActivityThread.java:3683)
ERROR   AndroidRuntime      at java.lang.reflect.Method.invokeNative(Native Method)
ERROR   AndroidRuntime      at java.lang.reflect.Method.invoke(Method.java:507)
ERROR   AndroidRuntime      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
ERROR   AndroidRuntime      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
ERROR   AndroidRuntime      at dalvik.system.NativeStart.main(Native Method)
ERROR   AndroidRuntime  Caused by: java.lang.NullPointerException
ERROR   AndroidRuntime      at com.cmbryan.android.Mp3AndFftTest.onCreate(Mp3AndFftTest.java:17)
ERROR   AndroidRuntime      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
ERROR   AndroidRuntime      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
ERROR   AndroidRuntime      ... 11 more

我在安多尔特清单中有正确的权限, 并且测试了模拟器和一个真正的设备。我错过了什么? 是因为我在使用蚊帐吗?

Answer 1

第17行是:

Gdx.files.isExternalStorageAvailable();

? Gdx. files 是无效的。这是因为您没有运行 GDX 初始化代码, 在 Gdx 中设置全局快捷键。您需要创建一个 ApplicationListener 并将其传递到 AndroidApplication. 初始化(.) 。



这里的例子如下:
                
                    时间：2012-05-21 19:27:14
                
                
            
   
      

   
   	问题回答
   
      
   	
也许不是理想的解决办法,但你也可以使用

com.badlogic.gdx.backends.lwjgl.LwjglFiles


class directly.
This is the class for creating the Gdx.files object.
    
       
            
                
                    时间：2012-08-27 21:23:58
                
                
            
   
   
       

   
   

  
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Answer 2

也许不是理想的解决办法,但你也可以使用

com.badlogic.gdx.backends.lwjgl.LwjglFiles

class directly. This is the class for creating the Gdx.files object.

友情链接