我试图实现以下编程方式(而不是通过XML声明):

<RelativeLayout...>
   <TextView ...
      android:id="@+id/label1" />
   <TextView ...
      android:id="@+id/label2"
      android:layout_below: "@id/label1" />
</RelativeLayout>

换句话说,我如何使第二个TextView出现在第一个下面,但我想在代码中这样做:

RelativeLayout layout = new RelativeLayout(this);
TextView label1 = new TextView(this);
TextView label2 = new TextView(this);
...
layout.addView(label1);
layout.addView(label2);
setContentView(layout);

更新:

谢谢,TreeUK。我理解大致的方向,但还是不行——B和A重叠。我做错了什么?

RelativeLayout layout = new RelativeLayout(this);
TextView tv1 = new TextView(this);
tv1.setText("A");

TextView tv2 = new TextView(this);
tv2.setText("B");
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(
        RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.FILL_PARENT);
lp.addRule(RelativeLayout.RIGHT_OF, tv1.getId());

layout.addView(tv1);        
layout.addView(tv2, lp);

当前回答

如果你真的想手动布局,我建议不要使用标准布局。这是一个kotlin的例子:

class ProgrammaticalLayout @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0) : ViewGroup(context, attrs, defStyleAttr) { 
    private val firstTextView = TextView(context).apply {
        test = "First Text"
    }

    private val secondTextView = TextView(context).apply {
        text = "Second Text"
    }

    init {
        addView(firstTextView)
        addView(secondTextView)
    }

    override fun onLayout(changed: Boolean, left: Int, top: Int, right: Int, bottom: Int) {
        // center the views verticaly and horizontaly
        val firstTextLeft = (measuredWidth - firstTextView.measuredWidth) / 2
        val firstTextTop = (measuredHeight - (firstTextView.measuredHeight + secondTextView.measuredHeight)) / 2
        firstTextView.layout(firstTextLeft,firstTextTop, firstTextLeft + firstTextView.measuredWidth,firstTextTop + firstTextView.measuredHeight)

        val secondTextLeft = (measuredWidth - secondTextView.measuredWidth) / 2
        val secondTextTop = firstTextView.bottom
        secondTextView.layout(secondTextLeft,secondTextTop, secondTextLeft + secondTextView.measuredWidth,secondTextTop + secondTextView.measuredHeight)
    }

    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) { 
        // just assume we`re getting measured exactly by the parent
        val measuredWidth = MeasureSpec.getSize(widthMeasureSpec)
        val measuredHeight = MeasureSpec.getSize(heightMeasureSpec)

        firstTextView.measures(MeasureSpec.makeMeasureSpec(meeasuredWidth, MeasureSpec.AT_MOST), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED))
        secondTextView.measures(MeasureSpec.makeMeasureSpec(meeasuredWidth, MeasureSpec.AT_MOST), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED))

        setMeasuredDimension(measuredWidth, measuredHeight)
    }
}

这可能会让你知道它是如何工作的

其他回答

长话短说: 使用相对布局可以在布局中放置元素。

创建一个新的RelativeLayout。LayoutParams RelativeLayout。LayoutParams lp = new RelativeLayout.LayoutParams(…) (不管…填充父内容或包装内容,绝对数字(如果你必须,或引用XML资源) 添加规则: 规则指的是父级或层次结构中的其他“兄弟”。 lp.addRule(使用。下面,someOtherView.getId ()) lp.addRule (RelativeLayout.ALIGN_PARENT_LEFT) 应用布局参数:最“健康”的方法是: parentLayout。addView (myView lp)

注意:不要从布局回调中更改布局。这样做很有诱惑力,因为这是视图获得实际大小的时候。然而,在这种情况下,预期会出现意想不到的结果。

根据我所能够拼凑的内容,您必须使用LayoutParams添加视图。

LinearLayout linearLayout = new LinearLayout(this);

RelativeLayout.LayoutParams relativeParams = new RelativeLayout.LayoutParams(
        LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
relativeParams.addRule(RelativeLayout.ALIGN_PARENT_TOP);

parentView.addView(linearLayout, relativeParams);

所有功劳都归功于sechastain,以编程方式相对定位您的项目,您必须为它们分配id。

TextView tv1 = new TextView(this);
tv1.setId(1);
TextView tv2 = new TextView(this);
tv2.setId(2);

然后addRule(使用。RIGHT_OF tv1.getId ());

调用

tv1.setId(1) 

tv1.setText("A");

我花了4个小时来解决这个问题。终于意识到你不能使用0作为视图id。你可能认为NO_ID == -1是允许的,但是如果你把它给你的视图,事情就会变得混乱…

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //setContentView(R.layout.activity_main);

        final RelativeLayout relativeLayout = new RelativeLayout(this);
        final TextView tv1 = new TextView(this);
        tv1.setText("tv1 is here");
        // Setting an ID is mandatory.
        tv1.setId(View.generateViewId());
        relativeLayout.addView(tv1);


        final TextView tv2 = new TextView(this);
        tv2.setText("tv2 is here");

        // We are defining layout params for tv2 which will be added to its  parent relativelayout.
        // The type of the LayoutParams depends on the parent type.
        RelativeLayout.LayoutParams tv2LayoutParams = new  RelativeLayout.LayoutParams(
            RelativeLayout.LayoutParams.WRAP_CONTENT,
            RelativeLayout.LayoutParams.WRAP_CONTENT);

        //Also, we want tv2 to appear below tv1, so we are adding rule to tv2LayoutParams.
        tv2LayoutParams.addRule(RelativeLayout.BELOW, tv1.getId());

        //Now, adding the child view tv2 to relativelayout, and setting tv2LayoutParams to be set on view tv2.
        relativeLayout.addView(tv2);
        tv2.setLayoutParams(tv2LayoutParams);
        //Or we can combined the above two steps in one line of code
        //relativeLayout.addView(tv2, tv2LayoutParams);

        this.setContentView(relativeLayout);
    }

}