如何在另一个视图下添加动态按钮？

Question

在android中,我有一段代码:

// RelativeLayout with id is "root": main.xml
<EditText 
    android:id="@+id/pref_edit_text"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:hint="Text to share in preference"
/>
// This is the button I want to add to main.xml
 <Button 
    android:id="@+id/save_button"
    android:layout_below="@id/pref_edit_text"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Save"
/>

在我的活动,随着RelativeLayout.LayoutParam我可以添加button的位置left, right, top, bottom的root观点,但我不能添加below其他视图或等...!所以,任何人都可以给一个建议添加view内容涉及与其他view的RelativeLayout动态？

Answer 1

干得好.这将完成您要做的事情:

public class ExampleActivity extends Activity {
private RelativeLayout rl;
private EditText editText;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_example);

    rl = (RelativeLayout) findViewById(R.id.main_rl);
    editText = (EditText) findViewById(R.id.pref_edit_text);

    Button button = new Button(this);
    button.setText("Save");

    // create the layout params that will be used to define how your
    // button will be displayed
    RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
            LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

    // add the rule that places your button below your EditText object
    params.addRule(RelativeLayout.BELOW, editText.getId());

    // set the layoutParams on the button
    button.setLayoutParams(params);

    // add button to your RelativeLayout
    rl.addView(button);
}
}