how to integrate a facebook api

I have created an app and I have integrated it with Facebook.

The problem is there is a class file named Example in Facebook package and it is associated with the xml file named fb but the data are not retrieved from the fb.xml it shows errors as

setContentView(R.layout.fb);
            mLoginButton = (LoginButton) findViewById(R.id.login);
            mText = (TextView) Example.this.findViewById(R.id.txt);
//          mRequestButton = (Button) findViewById(R.id.requestButton);
            mPostButton = (Button) findViewById(R.开发者_Python百科id.postButton);
            mDeleteButton = (Button) findViewById(R.id.deletePostButton);

Any idea how to solve the issue?

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Try checking if the buttons equals null. If so, they could not be found in the xml. That means that your xml contain errors. What is the error log?