java - 相对布局中的 Textview 不会以编程方式出现在彼此下方

Question

我试图将一些 TextView 放置在 RelativeLayout 中的另一个 TextView 下方，但由于某种原因它不起作用:

import android.graphics.Color;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.widget.TextViewCompat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.GridLayout.LayoutParams;
import android.widget.RelativeLayout;
import android.widget.TextView;

import com.companyname.projectname.R;

import static com.companyname.projectname.R.id.FL_relativeLayout;


public class FragmentFL extends android.support.v4.app.Fragment {

    public FragmentFL() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        return inflater.inflate(R.layout.fragment_fl, container, false);
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        View v = getView();
        assert v != null;

        RelativeLayout relativelayout = v.findViewById(FL_relativeLayout);

        RelativeLayout.LayoutParams rlp = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

        // add text views
        TextView txt1 = new TextView(getActivity());
        txt1.setText("Blue");
        TextViewCompat.setTextAppearance(txt1, android.R.style.TextAppearance_Large);
        txt1.setTextColor(Color.BLACK);

        TextView txt2 = new TextView(getActivity());
        txt2.setText("Black");
        TextViewCompat.setTextAppearance(txt2, android.R.style.TextAppearance_Medium);
        txt2.setTextColor(Color.BLACK);

        TextView txt3 = new TextView(getActivity());
        txt3.setText("Green");
        TextViewCompat.setTextAppearance(txt3, android.R.style.TextAppearance_Large);
        txt3.setTextColor(Color.BLACK);

        TextView txt4 = new TextView(getActivity());
        txt4.setText("Red");
        TextViewCompat.setTextAppearance(txt4, android.R.style.TextAppearance_Medium);
        txt4.setTextColor(Color.BLACK);

        TextView txt5 = new TextView(getActivity());
        txt5.setText("Yellow");
        TextViewCompat.setTextAppearance(txt5, android.R.style.TextAppearance_Large);
        txt5.setTextColor(Color.BLACK);

        TextView txt6 = new TextView(getActivity());
        txt6.setText("White");
        TextViewCompat.setTextAppearance(txt6, android.R.style.TextAppearance_Medium);
        txt6.setTextColor(Color.BLACK);

        txt1.setId(View.generateViewId());
        txt2.setId(View.generateViewId());
        txt3.setId(View.generateViewId());
        txt4.setId(View.generateViewId());
        txt5.setId(View.generateViewId());
        txt6.setId(View.generateViewId());

        rlp.addRule(RelativeLayout.BELOW, txt1.getId());
        rlp.addRule(RelativeLayout.BELOW, txt2.getId());
        rlp.addRule(RelativeLayout.BELOW, txt3.getId());
        rlp.addRule(RelativeLayout.BELOW, txt4.getId());
        rlp.addRule(RelativeLayout.BELOW, txt5.getId());
        txt2.setLayoutParams(rlp);
        txt3.setLayoutParams(rlp);
        txt4.setLayoutParams(rlp);
        txt5.setLayoutParams(rlp);
        txt6.setLayoutParams(rlp);

        relativelayout.addView(txt1);
        relativelayout.addView(txt2);
        relativelayout.addView(txt3);
        relativelayout.addView(txt4);
        relativelayout.addView(txt5);
        relativelayout.addView(txt6);


        super.onActivityCreated(savedInstanceState);
    }
}

Answer 1

您需要为每个 TextView 使用不同的 LayoutParams，如

 rlp.addRule(RelativeLayout.BELOW, txt1.getId());
 rlp1.addRule(RelativeLayout.BELOW, txt2.getId());
 rlp2.addRule(RelativeLayout.BELOW, txt3.getId());
 rlp3.addRule(RelativeLayout.BELOW, txt4.getId());
 rlp4.addRule(RelativeLayout.BELOW, txt5.getId());

    txt2.setLayoutParams(rlp);
    txt3.setLayoutParams(rlp1);
    txt4.setLayoutParams(rlp2);
    txt5.setLayoutParams(rlp3);
    txt6.setLayoutParams(rlp4);