设置视图大小

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="视图宽高采用wrap_content定义"
        android:textColor="#000000"
        android:background="#00ff00"
        android:layout_marginTop="5dp"
        android:textSize="17sp"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="视图宽高采用match_parent定义"
        android:textColor="#000000"
        android:background="#00ff00"
        android:layout_marginTop="5dp"
        android:textSize="17sp"/>

    <TextView
        android:layout_width="300dp"
        android:layout_height="wrap_content"
        android:text="视图宽高采用固定大小"
        android:textColor="#000000"
        android:background="#00ff00"
        android:layout_marginTop="5dp"
        android:textSize="17sp"/>

    <TextView
        android:id="@+id/tv_code"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="通过代码指定视图宽度"
        android:textColor="#000000"
        android:background="#00ff00"
        android:layout_marginTop="5dp"
        android:textSize="17sp"/>

</LinearLayout>

package com.example.chapter003;

import android.os.Bundle;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

import com.example.chapter003.Utils.Utils;

public class ViewBorderActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_border);
        TextView tv_code = findViewById(R.id.tv_code);
        ViewGroup.LayoutParams Params = tv_code.getLayoutParams();
        Params.width = Utils.dip2px(this, 300);
        tv_code.setLayoutParams(Params);
    }
}

package com.example.chapter003.Utils;

import android.content.Context;

public class Utils {
    public static int dip2px(Context context,float dpValue){
        float scale = context.getResources().getDisplayMetrics().density;
        return (int)(dpValue * scale + 0.5f);
    }
}