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?
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
以上代码已在API级别30中弃用。现在您可以使用以下代码
val width = windowManager.currentWindowMetrics.bounds.width()
val height = windowManager.currentWindowMetrics.bounds.height()
此方法报告包括所有系统栏区域的窗口大小,而Display#getSize(Point)报告不包括导航栏和显示剪切区域的区域。Display#getSize(Point)报告的值可通过以下方式获得:
val metrics = windowManager.currentWindowMetrics
// Gets all excluding insets
val windowInsets = metrics.windowInsets
var insets: Insets = windowInsets.getInsets(WindowInsets.Type.navigationBars())
val cutout = windowInsets.displayCutout
if (cutout != null) {
val cutoutSafeInsets = Insets.of(cutout.safeInsetLeft, cutout.safeInsetTop, cutout.safeInsetRight, cutout.safeInsetBottom)
insets = Insets.max(insets, cutoutSafeInsets)
}
val insetsWidth = insets.right + insets.left
val insetsHeight = insets.top + insets.bottom
// Legacy size that Display#getSize reports
val legacySize = Size(metrics.bounds.width() - insetsWidth, metrics.bounds.height() - insetsHeight)
来源:WindowManager#getCurrentWindowMetrics()
其他回答
它可能无法回答您的问题,但如果你需要一个视图的维度,但你的代码在尚未布局时(例如在onCreate()中)正在执行,你可以使用View.getViewTreeObserver().addOnGlobalLayoutListener()设置一个ViewTreeObserver.OnGlobalLayout侦听器,并将需要该视图的相关代码放入尺寸。布局布局完成后,将调用侦听器的回调。
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;
}
在活动的onCreate中,有时需要知道布局可用空间的精确尺寸。经过一番思考,我想出了这种方法。
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
startActivityForResult(new Intent(this, Measure.class), 1);
// Return without setting the layout, that will be done in onActivityResult.
}
@Override
protected void onActivityResult (int requestCode, int resultCode, Intent data) {
// Probably can never happen, but just in case.
if (resultCode == RESULT_CANCELED) {
finish();
return;
}
int width = data.getIntExtra("Width", -1);
// Width is now set to the precise available width, and a layout can now be created. ...
}
}
public final class Measure extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
// Create a LinearLayout with a MeasureFrameLayout in it.
// Just putting a subclass of LinearLayout in works fine, but to future proof things, I do it this way.
LinearLayout linearLayout = new LinearLayout(this);
LinearLayout.LayoutParams matchParent = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
MeasureFrameLayout measureFrameLayout = new MeasureFrameLayout(this);
measureFrameLayout.setLayoutParams(matchParent);
linearLayout.addView(measureFrameLayout);
this.addContentView(linearLayout, matchParent);
// measureFrameLayout will now request this second activity to finish, sending back the width.
}
class MeasureFrameLayout extends FrameLayout {
boolean finished = false;
public MeasureFrameLayout(Context context) {
super(context);
}
@SuppressLint("DrawAllocation")
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (finished) {
return;
}
finished = true;
// Send the width back as the result.
Intent data = new Intent().putExtra("Width", MeasureSpec.getSize(widthMeasureSpec));
Measure.this.setResult(Activity.RESULT_OK, data);
// Tell this activity to finish, so the result is passed back.
Measure.this.finish();
}
}
}
如果出于某种原因,您不想将另一个活动添加到Android清单中,可以这样做:
public class MainActivity extends Activity {
static Activity measuringActivity;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
Bundle extras = getIntent().getExtras();
if (extras == null) {
extras = new Bundle();
}
int width = extras.getInt("Width", -2);
if (width == -2) {
// First time in, just start another copy of this activity.
extras.putInt("Width", -1);
startActivityForResult(new Intent(this, MainActivity.class).putExtras(extras), 1);
// Return without setting the layout, that will be done in onActivityResult.
return;
}
if (width == -1) {
// Second time in, here is where the measurement takes place.
// Create a LinearLayout with a MeasureFrameLayout in it.
// Just putting a subclass of LinearLayout in works fine, but to future proof things, I do it this way.
LinearLayout linearLayout = new LinearLayout(measuringActivity = this);
LinearLayout.LayoutParams matchParent = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
MeasureFrameLayout measureFrameLayout = new MeasureFrameLayout(this);
measureFrameLayout.setLayoutParams(matchParent);
linearLayout.addView(measureFrameLayout);
this.addContentView(linearLayout, matchParent);
// measureFrameLayout will now request this second activity to finish, sending back the width.
}
}
@Override
protected void onActivityResult (int requestCode, int resultCode, Intent data) {
// Probably can never happen, but just in case.
if (resultCode == RESULT_CANCELED) {
finish();
return;
}
int width = data.getIntExtra("Width", -3);
// Width is now set to the precise available width, and a layout can now be created.
...
}
class MeasureFrameLayout extends FrameLayout {
boolean finished = false;
public MeasureFrameLayout(Context context) {
super(context);
}
@SuppressLint("DrawAllocation")
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (finished) {
return;
}
finished = true;
// Send the width back as the result.
Intent data = new Intent().putExtra("Width", MeasureSpec.getSize(widthMeasureSpec));
MainActivity.measuringActivity.setResult(Activity.RESULT_OK, data);
// Tell the (second) activity to finish.
MainActivity.measuringActivity.finish();
}
}
要获得屏幕尺寸,请使用显示度量
DisplayMetrics displayMetrics = new DisplayMetrics();
if (context != null)
WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display defaultDisplay = windowManager.getDefaultDisplay();
defaultDisplay.getRealMetrics(displayMetrics);
}
以像素为单位获取高度和宽度
int width =displayMetrics.widthPixels;
int height =displayMetrics.heightPixels;
这不是更好的解决方案吗?DisplayMetrics提供了您所需的一切,并从API 1开始工作。
public void getScreenInfo(){
DisplayMetrics metrics = new DisplayMetrics();
getActivity().getWindowManager().getDefaultDisplay().getMetrics(metrics);
heightPixels = metrics.heightPixels;
widthPixels = metrics.widthPixels;
density = metrics.density;
densityDpi = metrics.densityDpi;
}
您也可以使用getRealMetrics获得实际显示(包括屏幕装饰,如状态栏或软件导航栏),但这仅适用于17+。
我错过了什么吗?