小编Wal*_*rld的帖子

好的.所以我在Main中开始我的活动,抓住FragmentManager并实例化一个需要返回View的Fragment.好.所以我扩展了一个LinearLayout以便有一些东西可以返回.我的活动和片段很高兴,但我不是.

我在父ViewGroup中创建的三个LinearLayouts(下面的代码).我通过计算儿童并通过设置背景颜色来相互对比来验证这一点.父级也会根据我对子项的高度来改变大小(当我没有在父级上声明任何LayoutParams时).

public class Mainmenu extends LinearLayout {
private ArrayList<LinearLayout> panes = new ArrayList<LinearLayout>();
private Context context;
private final int
    LEFT = 0, CENTER = 1, RIGHT = 2;

public Mainmenu(Context c) {
    super(c);
    context = c;
    setBackgroundColor(Color.WHITE);
    setOrientation(HORIZONTAL);
    setLayoutParams(
            new LinearLayout.LayoutParams(
                    LinearLayout.LayoutParams.FILL_PARENT,
                    LinearLayout.LayoutParams.FILL_PARENT));


    for(int i=0;i<=RIGHT;i++){                                      //Create the (3) Panes
        LinearLayout ll = new LinearLayout(context);
        ll.setLayoutParams(
                new LinearLayout.LayoutParams(300,
                        LinearLayout.LayoutParams.FILL_PARENT));
        switch(i){
        case LEFT | RIGHT:
            ll.setBackgroundColor(Color.DKGRAY);
        default:
            ll.setBackgroundColor(Color.BLACK);
        }
        ll.setOrientation(LinearLayout.VERTICAL);
        ll.setVisibility(VISIBLE);
        ll.setWillNotDraw(false);
        panes.add(i, ll);
        addView(ll);
    }

    LinearLayout.LayoutParams buttons =
        new LinearLayout.LayoutParams(100, …