我对 Java 编程还比较陌生，我想打开一个带有多个不同 Activity 按钮的 fragment 。但是，我总是在以下位置收到错误(...已在...中定义):
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
此外，在其他变体中它不起作用，并且出现更多错误。
这是我的 fragment 的完整代码:
public DashboardFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_dashboard, container, false);
ImageButton button = (ImageButton) rootView.findViewById(R.id.stundenplanbtn);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Stundenplan.class);
startActivity(intent);
}
});
return rootView;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_dashboard, container, false);
ImageButton button2 = (ImageButton) rootView.findViewById(R.id.vertretungsbtn);
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Vertretungsplan.class);
startActivity(intent);
}
});
return rootView;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_dashboard, container, false);
ImageButton button2 = (ImageButton) rootView.findViewById(R.id.essenbtn);
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Essen.class);
startActivity(intent);
}
});
return rootView;
}
}
最佳答案
你真正想要的是这样的:
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_dashboard, container, false);
ImageButton button = (ImageButton) rootView.findViewById(R.id.stundenplanbtn);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Stundenplan.class);
startActivity(intent);
}
});
ImageButton button2 = (ImageButton) rootView.findViewById(R.id.vertretungsbtn);
button2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Vertretungsplan.class);
startActivity(intent);
}
});
return rootView;
}
此外，在 Android 特定上下文中，您实际上并不需要进行所有 ImageButton 转换等，因为您没有使用 ImageButton 类的任何特定方法，而且它扩展您可以简单使用的View类:
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_dashboard, container, false);
rootView.findViewById(R.id.stundenplanbtn).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Stundenplan.class);
startActivity(intent);
}
});
rootView.findViewById(R.id.vertretungsbtn).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Vertretungsplan.class);
startActivity(intent);
}
});
return rootView;
}
请注意，这里唯一的事情不是创建按钮变量/引用，因此这只是一个小小的改进。但如果你现在感到困惑，请忽略并使用第一个。
关于java - 在具有多个按钮的 fragment 中启动 Activity ，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/44637355/