Android 线性布局不显示以编程方式添加的项目

我试图以编程方式向线性布局添加文本视图和按钮

按钮正在显示，但文本视图没有显示

这是我的密码：

        LinearLayout main = (LinearLayout) findViewById(R.id.mainlayout);
        LinearLayout first = new LinearLayout(this);

        LayoutParams fparams = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, 5.0f);
        LayoutParams tvparams = new LayoutParams(0, LayoutParams.WRAP_CONTENT);
        LayoutParams btparams = new LayoutParams(0, LayoutParams.WRAP_CONTENT);

        first.setLayoutParams(fparams);
        first.setOrientation(LinearLayout.HORIZONTAL);

        TextView tv = new TextView(this);
        tvparams.weight = 3.0f;
        tv.setLayoutParams(tvparams);

        Button bt = new Button(this);
        btparams.weight = 2.0f;
        bt.setLayoutParams(btparams);

        first.addView(bt);
        first.addView(tv);      
        main.addView(first);

---

好的，尝试以编程方式设置

        LinearLayout myLayout = (LinearLayout)findViewById(R.id.parent);
 LayoutParams fparams = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, 5.0f);
        LayoutParams tvparams = new LayoutParams(0, LayoutParams.WRAP_CONTENT,3.0f);
        LayoutParams btparams = new LayoutParams(0, LayoutParams.WRAP_CONTENT,2.0f);
        LinearLayout first = new LinearLayout(this);
        first.setLayoutParams(fparams);
        first.setOrientation(LinearLayout.HORIZONTAL);

        TextView tv = new TextView(this);
        tv.setText("asdsad");
        tv.setLayoutParams(tvparams);

        Button bt = new Button(this);
        bt.setLayoutParams(btparams);

        first.addView(bt);
        first.addView(tv);      
        myLayout.addView(first);

---

希望它能帮助我正确地工作。

尝试在

TextView

上设置一些文本。使用它的

setText（）

方法

谢谢你的回答。另一个答案更切题。