<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity" android:id="@+id/f"> <Button android:id="@+id/button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="颜色选择" android:background="#00BCD4" android:layout_centerHorizontal="true" android:layout_centerVertical="true" android:onClick="gh"/> </RelativeLayout>
package com.example.back; import androidx.appcompat.app.AppCompatActivity; import android.app.AlertDialog; import android.content.DialogInterface; import android.graphics.Color; import android.os.Bundle; import android.view.View; import android.widget.RelativeLayout; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } String b="#000000"; public void gh(View view) { AlertDialog dialog; AlertDialog.Builder builder = new AlertDialog.Builder(this) .setTitle("设置布局背景") .setIcon(R.drawable.ic_launcher_background) .setSingleChoiceItems(new String[]{"白色", "黑色", "红色", }, 0,new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { // 点单选按钮时发生的事件,这里which表示你点的单选按钮是第几个 switch (which){ case 0:b="#FAF9F9" ; break; case 1:b="#000000" ; break; case 2: b="#F44336"; break; } } }) .setPositiveButton("确定", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { //点确定按钮时发生的事件 ((RelativeLayout)findViewById(R.id.f)).setBackgroundColor(Color.parseColor(b)); dialog.dismiss(); } })//添加“确定”按钮 .setNegativeButton("取消", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // 点取消按钮发生的事件 dialog.dismiss(); } }); dialog = builder.create(); dialog.show(); } }