我是Android开发的新手,所以这可能非常简单。但是,我找不到任何对我有用的东西。
我通过以下代码成功地将多个framelayout添加到线性布局中:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
LinearLayout fragmentContainer=(LinearLayout) findViewById(R.id.fragment_container);
fragmentContainer.setOrientation(LinearLayout.VERTICAL);
//if (findViewById(R.id.fragment_container) != null) {
for(int i=1;i<10;i++){
//create a new TextFrag object
TextFrag textFragment=new TextFrag();
//pass arguments to the textFrag Object with the Fragment Number
Bundle args=new Bundle();
args.putInt("FragNumber", i);
textFragment.setArguments(args);
//Create a new Frame Layout for Each Fragment. This is useful if you want to switch fragments at runtime
//Dont know exact details yet
FrameLayout fragmentFrame=new FrameLayout(this);
//set a unique id for the FrameLayout
fragmentFrame.setId(i);
//Define the Frame Layout Params
FrameLayout.LayoutParams params=new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
//Add the Fragment to the Frame Layout
getSupportFragmentManager().beginTransaction().add(fragmentFrame.getId(),textFragment).commit();
//Add the Frame Layout to the Linear Layout
fragmentContainer.addView(fragmentFrame);
}
}
所以在稍后的程序中,我想引用这些framelayouts,我想,因为我知道ID,我可以使用getViewById。
这似乎不起作用。我通过添加一个名为testFrame的冗余FrameLayout对象,稍微修改了上面的代码,如下所示:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
LinearLayout fragmentContainer=(LinearLayout) findViewById(R.id.fragment_container);
fragmentContainer.setOrientation(LinearLayout.VERTICAL);
//if (findViewById(R.id.fragment_container) != null) {
for(int i=1;i<10;i++){
//create a new TextFrag object
TextFrag textFragment=new TextFrag();
//pass arguments to the textFrag Object with the Fragment Number
Bundle args=new Bundle();
args.putInt("FragNumber", i);
textFragment.setArguments(args);
//Create a new Frame Layout for Each Fragment. This is useful if you want to switch fragments at runtime
//Dont know exact details yet
FrameLayout fragmentFrame=new FrameLayout(this);
//set a unique id for the FrameLayout
fragmentFrame.setId(i);
//Define the Frame Layout Params
FrameLayout.LayoutParams params=new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
//CHANGED CODE STARTS HERE
int theId=i;
FrameLayout testFrame=(FrameLayout) findViewById(theId);
if(testFrame!=null){
//Add the Fragment to the Frame Layout
getSupportFragmentManager().beginTransaction().add(testFrame.getId(),textFragment).commit();
//Add the Frame Layout to the Linear Layout
fragmentContainer.addView(testFrame);
}
//CHANGED CODE ENDS HERE
}
}
基本上,它不再显示任何framelayout,因为testFrame对象现在为null。关于我做错什么的任何想法?
答案 0 :(得分:0)
感谢Luksprog的回答。简单地创建元素并为其分配id是不够的。它需要添加到R文件中引用的现有视图中。在我的例子中,现有的视图是R.id.fragment_container