我是Andriod的新手并且很难在我的GLSurfaceView上添加控件(视图)。我希望将其添加到角落。 (比如说右下角) 最初我想添加Joystick之类的小部件,但起初我想添加“Left”,“Right”,“Top”,“Down”按钮。 我创建了一个布局XML文件,如下所示:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<View
android:id="@+id/viewControls"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/relativeLayout1"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
<RelativeLayout
android:id="@+id/relativeLayout1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="140dp" >
</RelativeLayout>
<Button
android:id="@+id/buttonR"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="@+id/relativeLayout1"
android:text="R" />
<Button
android:id="@+id/buttonL"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="L" />
</RelativeLayout>
在我的活动中,我尝试了如下:
public class MyOpenGL2Activity extends Activity {
private GLSurfaceView mGLview;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
mGLview=new MyOpenGL2SurfaceView(this);
FrameLayout flayout=new FrameLayout(this);
flayout.addView(mGLview);
View controller=findViewById(R.id.viewControls);
flayout.addView(controller);
setContentView(flayout);
}
...
但应用程序崩溃说
05-05 14:40:08.015:W / dalvikvm(2258):threadid = 1:线程退出 未捕获的异常(组= 0x40a841f8)05-05 14:40:08.023: E / AndroidRuntime(2258):致命异常:主05-05 14:40:08.023: E / AndroidRuntime(2258):java.lang.RuntimeException:无法启动 活动ComponentInfo {ausoft.opengl / ausoft.opengl.MyOpenGL2Activity}: java.lang.NullPointerException 05-05 14:40:08.023: E / AndroidRuntime(2258):at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1955) 05-05 14:40:08.023:E / AndroidRuntime(2258):at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1980) 05-05 14:40:08.023:E / AndroidRuntime(2258):at android.app.ActivityThread.access $ 600(ActivityThread.java:122)05-05 14:40:08.023:E / AndroidRuntime(2258):at android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1146) 05-05 14:40:08.023:E / AndroidRuntime(2258):at android.os.Handler.dispatchMessage(Handler.java:99)05-05 14:40:08.023:E / AndroidRuntime(2258):at android.os.Looper.loop(Looper.java:137)05-05 14:40:08.023: E / AndroidRuntime(2258):at android.app.ActivityThread.main(ActivityThread.java:4340)05-05 14:40:08.023:E / AndroidRuntime(2258):at java.lang.reflect.Method.invokeNative(Native Method)05-05 14:40:08.023:E / AndroidRuntime(2258):at java.lang.reflect.Method.invoke(Method.java:511)05-05 14:40:08.023: E / AndroidRuntime(2258):at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:784) 05-05 14:40:08.023:E / AndroidRuntime(2258):at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)05-05 14:40:08.023:E / AndroidRuntime(2258):at dalvik.system.NativeStart.main(Native Method)05-05 14:40:08.023: E / AndroidRuntime(2258):引起:java.lang.NullPointerException 05-05 14:40:08.023:E / AndroidRuntime(2258):at android.view.ViewGroup.addView(ViewGroup.java:3165)05-05 14:40:08.023:E / AndroidRuntime(2258):at android.view.ViewGroup.addView(ViewGroup.java:3152)05-05 14:40:08.023:E / AndroidRuntime(2258):at ausoft.opengl.MyOpenGL2Activity.onCreate(MyOpenGL2Activity.java:35) 05-05 14:40:08.023:E / AndroidRuntime(2258):at android.app.Activity.performCreate(Activity.java:4465)05-05 14:40:08.023:E / AndroidRuntime(2258):at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 05-05 14:40:08.023:E / AndroidRuntime(2258):at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1919) 05-05 14:40:08.023:E / AndroidRuntime(2258):... 11更多
任何提示?
答案 0 :(得分:2)
您正在尝试findViewById(R.id.viewControls);
,但之前没有致电setContentView()
...视图viewControls
在哪里?
如果需要,可以像这样创建视图
View controller = new View(this.getApplicationContext());
或其他......