尝试使用 Wowza 在空对象引用 Android Studio 上调用虚拟方法

Question

我正在尝试使用 wowza 开始广播。我正在使用一个示例应用程序，当我编译时可以完美运行。

但是，当我尝试在自己的项目中使用它时，当我尝试启动广播时出现此错误：

E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.caper.teststream, PID: 26004
java.lang.NullPointerException: Attempt to invoke virtual method 'void com.wowza.gocoder.sdk.api.broadcast.WOWZBroadcastConfig.setStreamName(java.lang.String)' on a null object reference
at com.caper.teststream.WowzaCamera.start(WowzaCamera.java:80)
at com.caper.teststream.BroadcastActivity.onClick(BroadcastActivity.java:59)
at android.view.View.performClick(View.java:6891)
at android.widget.TextView.performClick(TextView.java:12651)
at android.view.View$PerformClick.run(View.java:26083)
at android.os.Handler.handleCallback(Handler.java:789)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6938)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

相机也不会显示在预览中

这是我的代码

public class BroadcastActivity extends AppCompatActivity
implements  View.OnClickListener {
WOWZCameraView mWowzaPreview;
WowzaCamera mWowza = null;
boolean mIsBroadcastStarted = false;
private boolean mPermissionsGranted = true;
private static int mPermissionCount = 0;
private String[] mRequiredPermissions = new String[]{
Manifest.permission.CAMERA,
Manifest.permission.RECORD_AUDIO,
Manifest.permission.READ_EXTERNAL_STORAGE
};
private static final int PERMISSIONS_REQUEST_WOWZA = 367;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_broadcast);
// Don't turn off screen while in this activity
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
mWowzaPreview =  findViewById(R.id.camera_preview);
Button broadcastBtn = findViewById(R.id.broadcast_button);
broadcastBtn.setOnClickListener(this);

}

@Override
public void onClick(View view) {
Button btn = (Button)view;
if(!mIsBroadcastStarted)
{
// Name of stream is assigned here
mWowza.start("myStream2");
mIsBroadcastStarted = true;
btn.setText("STOP");
} else {
mWowza.stop();
btn.setText("START");
mIsBroadcastStarted = false;
}

}
@Override
protected void onResume() {
super.onResume();
//Check appropriate permissions
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
mPermissionsGranted = hasPermissions(this, mRequiredPermissions);
if (!mPermissionsGranted)
ActivityCompat.requestPermissions(this, mRequiredPermissions, PERMISSIONS_REQUEST_WOWZA);
else {
initializeWowzaCamera();
}
} else {
mPermissionsGranted = true;
initializeWowzaCamera();
}
}
private boolean isInit = false;
private void initializeWowzaCamera(){
if (!isInit) {
mWowza = new WowzaCamera(BroadcastActivity.this, mWowzaPreview);
isInit = true;
}
if (mWowza != null) {
mWowza.onResume();
mWowzaPreview.onResume();
}
}
private static boolean hasPermissions(Context context, String[] permissions) {
for (String permission : permissions)
if (context.checkCallingOrSelfPermission(permission) != PackageManager.PERMISSION_GRANTED)
return false;
return true;
}

@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case PERMISSIONS_REQUEST_WOWZA: {
// If request is cancelled, the result arrays are empty.
// Check the result of each permission granted
mPermissionCount++;
for (int grantResult : grantResults) {
if (grantResult == PackageManager.PERMISSION_DENIED) {
mPermissionsGranted = false;
}
}
if (mPermissionsGranted && mPermissionCount == 3) {
initializeWowzaCamera();
}

if (!mPermissionsGranted && mPermissionCount == 3) {
mPermissionCount = 0;
finish();
}
return;
}
}
}

@Override
protected void onPause() {
if(mWowza!=null)
mWowza.onPause();
super.onPause();
}

@Override
protected void onDestroy() {
mWowza.stop();
super.onDestroy();
}
}

请帮忙

Answer 1

我认为您在检查是否已授予权限时没有调用 initializeWowzaCamera((。你的意思是？

if (mPermissionsGranted && grantResults.length == 3) {
initializeWowzaCamera();
}