我定义了一种方法来创建线性布局并将其添加到父布局。但它没有用。我想我犯了错误。
mqd_t mq;
struct mq_attr attr;
mq = mq_open("/randomMq", (O_RDONLY | O_CREAT), 0666, &attr);
printf("%d\n",mq);
答案 0 :(得分:1)
要向ConstraintLayout添加视图,必须使用ConstraintSet添加约束。
在为约束布局添加动态视图时,它与其他布局略有不同。您需要指定约束,如下所示: -
ConstraintLayout main = (ConstraintLayout) findViewById(R.id.mainLayout);
ConstraintSet set = new ConstraintSet();
LinearLayout linearLayout = new LinearLayout(MainActivity.this);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
linearLayout.setLayoutParams(params);
linearLayout.setOrientation(LinearLayout.HORIZONTAL);
linearLayout.setBackgroundColor(Color.RED);
main.addView(linearLayout,0);
set.clone(main);
set.connect(linearLayout.getId(), ConstraintSet.TOP, main.getId(), ConstraintSet.TOP, 60);
set.applyTo(main);