Unity开发过程中如何正确的拿到Screen的width和height

首先明确两个概念:

Screen.currentResolution - 指的是设备分辨率，比如:电脑上指的就是电脑的屏幕分辨率，手机上指的就是手机的屏幕分辨率。

Screen.width,Screen.height - 指的是使用该值的窗口的宽高，比如:在Scene窗口使用指的就是Scene窗口的宽高，在Game窗口使用，即运行编辑器时使用，指的就是Game窗口的宽高，在自定义的Window使用指的就是自定义的Window的宽高。

定义如下窗口，用来测试上述结论:

代码:

using UnityEngine;
using UnityEditor;


public class CustomWindow : EditorWindow
{
    static CustomWindow mWin;

    [MenuItem("自定义窗口/MyWin")]
    static void ShowWin()
    {
        mWin = GetWindow<CustomWindow>();
        mWin.titleContent = new GUIContent("MyWin");
        mWin.minSize = new Vector2(400, 200);
    }

    void OnGUI()
    {
        if (GUILayout.Button("ShowInfo", GUILayout.Width(200), GUILayout.Height(50)))
        {
            Debug.Log("Screen.width = " + Screen.width + "  Screen.height = " + Screen.height + " | currentResolution = " + Screen.currentResolution);
        }
    }
}

打印结果:

在游戏开发过程中，我们更多关注的是Game视图下的屏幕宽高。假如，我们想在自定的Window中获取Game视图的屏幕宽高，该如何做呢？

下面是NGUI-3.9.4中提供的获取Game视图屏幕宽高的方法:

static int mSizeFrame = -1;
static System.Reflection.MethodInfo s_GetSizeOfMainGameView;
static Vector2 mGameSize = Vector2.one;

/// <summary>
/// Size of the game view cannot be retrieved from Screen.width and Screen.height when the game view is hidden.
/// </summary>

static public Vector2 screenSize
{
    get
    {
        int frame = Time.frameCount;

        if (mSizeFrame != frame || !Application.isPlaying)
        {
            mSizeFrame = frame;

            if (s_GetSizeOfMainGameView == null)
            {
                System.Type type = System.Type.GetType("UnityEditor.GameView,UnityEditor");
                s_GetSizeOfMainGameView = type.GetMethod("GetSizeOfMainGameView",
                    System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
            }
            mGameSize = (Vector2)s_GetSizeOfMainGameView.Invoke(null, null);
        }
        return mGameSize;
    }
}

对于移动设备，个人理解Screen.width,Screen.height和Screen.currentResolution值是一样的(并未实际验证)。为了安全起见，个人建议，编辑器下和移动设备上最好用Screen.width,Screen.height统一起来。NGUI也是这个思路:

#if UNITY_EDITOR
static int mSizeFrame = -1;
static System.Reflection.MethodInfo s_GetSizeOfMainGameView;
static Vector2 mGameSize = Vector2.one;

/// <summary>
/// Size of the game view cannot be retrieved from Screen.width and Screen.height when the game view is hidden.
/// </summary>

static public Vector2 screenSize
{
    get
    {
        int frame = Time.frameCount;

        if (mSizeFrame != frame || !Application.isPlaying)
        {
            mSizeFrame = frame;

            if (s_GetSizeOfMainGameView == null)
            {
                System.Type type = System.Type.GetType("UnityEditor.GameView,UnityEditor");
                s_GetSizeOfMainGameView = type.GetMethod("GetSizeOfMainGameView",
                    System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
            }
            mGameSize = (Vector2)s_GetSizeOfMainGameView.Invoke(null, null);
        }
        return mGameSize;
    }
}
#else
    /// <summary>
    /// Size of the game view cannot be retrieved from Screen.width and Screen.height when the game view is hidden.
    /// </summary>

    static public Vector2 screenSize { get { return new Vector2(Screen.width, Screen.height); } }
#endif

这里再提供一个折叠屏手机展开或者闭合后屏幕适配的一个思路:

Update中检测Screen的size是否发生变化，如果发生变化就去刷新一下锚定设置。

代码:

using UnityEngine;

public class CheckScreen : MonoBehaviour
{
    int screenWidth, screenHeight;
    void Start()
    {
        screenWidth = Screen.width;
        screenHeight = Screen.height;
    }


    void Update()
    {
        if (screenWidth != Screen.width || screenHeight != Screen.height)
        {
            screenWidth = Screen.width;
            screenHeight = Screen.height;
            OnScreenChange();
        }
    }

    void OnScreenChange()
    {
        //发送消息-处理适配之 前 的一些操作
        //UI适配
        //3D适配
        //其他...
        //发送消息-处理适配之 后 的一些操作
    }
}