Android动态生成Relativelayout + button

要求：输入每行btn个数，输出一共200个btn。

直接上代码，参考了csdn上的博客 android：动态创建多个按钮

不需要任何XML文件即可显示出btn。

import androidx.appcompat.app.AppCompatActivity;

import android.content.Context;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RelativeLayout;

public class MainActivity extends AppCompatActivity {


    private EditText editNum;
    private Button addbtn;


    DisplayMetrics dm = new DisplayMetrics();


    //MainActivity().getMetrics(dm);
    int width = dm.widthPixels;
    int height = dm.heightPixels;
    Button[] btt = new Button[205];

    //RelativeLayout layout = new RelativeLayout(this);
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        final RelativeLayout rlayout = new RelativeLayout(this);
        RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);

        layoutParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT );
        RelativeLayout.LayoutParams layoutParams2 = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);

        layoutParams2.addRule(RelativeLayout.ALIGN_PARENT_LEFT );
        rlayout.setLayoutParams(layoutParams);
        editNum = new EditText(MainActivity.this);
        editNum.setHint("请输入个数");
        editNum.setLayoutParams(layoutParams2);
        addbtn = new Button(MainActivity.this);
        addbtn.setWidth(100);
        addbtn.setHeight(40);
        addbtn.setText("add");
        addbtn.setLayoutParams(layoutParams);
        rlayout.addView(editNum);
        rlayout.addView(addbtn);
        addbtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                int linenum = Integer.parseInt(editNum.getText().toString());
                DisplayMetrics dm = new DisplayMetrics();
                getWindowManager().getDefaultDisplay().getMetrics(dm);
                int width = dm.widthPixels;
                int height = dm.heightPixels;



                Button Btn[] = new Button[205];
                int j = -1;
                for  (int i=0; i<200; i++) {
                    Btn[i]=new Button(MainActivity.this);
                    Btn[i].setId(i);
                    Btn[i].setText("B"+i);
                    RelativeLayout.LayoutParams btParams = new RelativeLayout.LayoutParams ((width-50)/linenum,120);
                    if (i%linenum == 0) {
                        j++;
                    }
                    btParams.leftMargin = 10+ ((width-50)/linenum+10)*(i%linenum);
                    btParams.topMargin = 120 + 120*j;   
                    rlayout.addView(Btn[i],btParams);   
                }
            }
        });


        setContentView(rlayout);

    }

}

运行效果

参考博文：https://blog.csdn.net/lihengfang/article/details/8204238