Question

我一直在寻找这个问题的答案。我是Android的新手，并尝试通过java而不是xml以编程方式将项目添加到相对布局。我已经创建了一个测试类来尝试它，但项目保持堆叠而不是正确格式化。我现在只想在另一个下面使用一个TextView（最终我将使用参数的左侧和右侧，但我开始很简单。我缺少什么？

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ScrollView sv = new ScrollView(this);
    RelativeLayout ll = new RelativeLayout(this);
    ll.setId(99);
    sv.addView(ll);
    TextView tv = new TextView(this);
    tv.setText("txt1");
    tv.setId(1);
    TextView tv2 = new TextView(this);
    tv2.setText("txt2");
    tv2.setId(2);
    RelativeLayout.LayoutParams lay = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
    lay.addRule(RelativeLayout.ALIGN_PARENT_TOP);
    ll.addView(tv, lay);
    RelativeLayout.LayoutParams p = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
    p.addRule(RelativeLayout.ALIGN_BOTTOM, tv.getId());
    ll.addView(tv2, p);  this.setContentView(sv);};

Answer 1

    p.addRule(RelativeLayout.ALIGN_BOTTOM, tv.getId());

此行表示tv2的底部与tv的底部对齐 - 换句话说，它们将相互覆盖。您想要的属性大概是RelativeLayout.BELOW。但是，我强烈建议您使用xml。

Answer 2

使用：

p.addRule(RelativeLayout.BELOW, tv.getId());

Answer 3

你遗漏了各种各样的东西，首先ScrollView没有措施，用LayoutParams.FILL_PARENT或WRAP_CONTENT设置它，第二个; TextView1放错了所以TextView2，用lay.addRule设置TextView1位置（RelativeLayout.ALIGN_PARENT_TOP，RelativeLayout.TRUE）;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ScrollView sv = new ScrollView(this);
    RelativeLayout ll = new RelativeLayout(this);
    ll.setId(99);

    sv.addView(ll, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));

    TextView tv = new TextView(this);
    tv.setText("txt1");
    tv.setId(1);

    TextView tv2 = new TextView(this);
    tv2.setText("txt2");
    tv2.setId(2);
    RelativeLayout.LayoutParams lay = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
    lay.addRule(RelativeLayout.ALIGN_PARENT_TOP, RelativeLayout.TRUE);
    ll.addView(tv, lay);
    RelativeLayout.LayoutParams p = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
    p.addRule(RelativeLayout.ALIGN_BOTTOM, tv.getId());
    ll.addView(tv2, p);  
this.setContentView(sv);};

以编程方式将项添加到相对布局

3 个答案: