我创建了一些自定义元素,并希望以编程方式将它们放置在右上角(距离上边缘n个像素,距离右边缘m个像素)。因此,我需要获得屏幕宽度和屏幕高度,然后设置位置:

int px = screenWidth - m;
int py = screenHeight - n;

如何在主活动中获取screenWidth和screenHeight?


当前回答

我会这样包装getSize代码:

@SuppressLint("NewApi")
public static Point getScreenSize(Activity a) {
    Point size = new Point();
    Display d = a.getWindowManager().getDefaultDisplay();
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
        d.getSize(size);
    } else {
        size.x = d.getWidth();
        size.y = d.getHeight();
    }
    return size;
}

其他回答

在Kotlin要简单得多。

val displayMetrics = Resources.getSystem().displayMetrics
displayMetrics.heightPixels
displayMetrics.widthPixels

我使用了上述建议,并为我们的问题创建了一个kotlin版本。希望这为使用科特林的人提供一些额外的帮助:

private val screenDimensions: Int by lazy {
    val display = (context.getSystemService(Context.WINDOW_SERVICE) as WindowManager).defaultDisplay
    Point()
        .also { size ->
            when {
                Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1 -> display.getRealSize(size)
                else -> display.getSize(size)
            }
        }
}

screenDimensions.x // width
screenDimensions.y // height

此函数以英寸为单位返回近似屏幕大小。

public double getScreenSize()
{
        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        int width=dm.widthPixels;
        int height=dm.heightPixels;
        int dens=dm.densityDpi;
        double wi=(double)width/(double)dens;
        double hi=(double)height/(double)dens;
        double x = Math.pow(wi,2);
        double y = Math.pow(hi,2);
        double screenInches = Math.sqrt(x+y);
        return screenInches;
}

有一种使用DisplayMetrics(API 1)来实现这一点的方法并不过时,它可以避免try/catch混乱:

 // initialize the DisplayMetrics object
 DisplayMetrics deviceDisplayMetrics = new DisplayMetrics();

 // populate the DisplayMetrics object with the display characteristics
 getWindowManager().getDefaultDisplay().getMetrics(deviceDisplayMetrics);

 // get the width and height
 screenWidth = deviceDisplayMetrics.widthPixels;
 screenHeight = deviceDisplayMetrics.heightPixels;

创建一个类和方法,如下所示:

public MyPoint getScreenDimensionsAsPixel(Context context){
        WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
        Display display = windowManager.getDefaultDisplay();

        Point point = new Point();
        display.getSize(point);

        return new MyPoint(point.x, point.y);
    }

    public class MyPoint{
        private int width;
        private int height;

        public MyPoint(int width, int height) {
            this.width = width;
            this.height = height;
        }

        public int getWidth() {
            return width;
        }

        public void setWidth(int width) {
            this.width = width;
        }

        public int getHeight() {
            return height;
        }

        public void setHeight(int height) {
            this.height = height;
        }
    }

然后在代码中使用它们:

MyPoint myPoint = getScreenDimensionsAsPixel(MainActivity.this);
                Toast.makeText(MainActivity.this, "width: " + String.valueOf(myPoint.getWidth()) + "|" +
                        "height: " + String.valueOf(myPoint.getHeight()), Toast.LENGTH_LONG).show();