获取屏幕尺寸，以像素为单位
I created some custom elements, and I want to programmatically place them to the upper right corner (n pixels from the top edge and m pixels from the right edge). Therefore I need to get the screen width and screen height and then set position:
int px = screenWidth - m;
int py = screenHeight - n;
How do I get screenWidth and screenHeight in the main Activity?
转载于:https://stackoverflow.com/questions/1016896/get-screen-dimensions-in-pixels
If you want the display dimensions in pixels you can use getSize:
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int width = size.x;
int height = size.y;
If you're not in an Activity you can get the default Display via WINDOW_SERVICE:
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
If you are in a fragment and want to acomplish this just use Activity.WindowManager (in Xamarin.Android) or getActivity().getWindowManager() (in java).
Before getSize was introduced (in API level 13), you could use the getWidth and getHeight methods that are now deprecated:
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth(); // deprecated
int height = display.getHeight(); // deprecated
For the use case you're describing however, a margin/padding in the layout seems more appropriate.
Another way is: DisplayMetrics
A structure describing general information about a display, such as its size, density, and font scaling. To access the DisplayMetrics members, initialize an object like this:
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
We can use widthPixels to get information for:
"The absolute width of the display in pixels."
Example:
Log.d("ApplicationTagName", "Display width in px is " + metrics.widthPixels);
First get view (eg. by findViewById()) and then you can use getWidth() on the view itself.
One way is:
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth();
int height = display.getHeight();
It is deprecated, and you should try the following code instead. The first two lines of code gives you the DisplayMetrics objecs. This objects contains the fields like heightPixels,widthPixels.
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
int height = metrics.heightPixels;
int width = metrics.widthPixels;
It may not answer your question, but it could be useful to know (I was looking for it myself when I came to this question) that if you need a View's dimension but your code is being executed when its layout has not been laid out yet (for example in onCreate() ) you can setup a ViewTreeObserver.OnGlobalLayoutListener with View.getViewTreeObserver().addOnGlobalLayoutListener() and put the relevant code that needs the view's dimension there. The listener's callback will be called when the layout will have been laid out.
For dynamically scaling using XML there is an attribute called "android:layout_weight"
The below example, modified from synic's response on this thread, shows a button that takes up 75% of the screen (weight = .25) and a text view taking up the remaining 25% of the screen (weight = .75).
<LinearLayout android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight=".25"
android:text="somebutton">
<TextView android:layout_width="fill_parent"
android:layout_height="Wrap_content"
android:layout_weight=".75">
</LinearLayout>
I found this did the trick.
Rect dim = new Rect();
getWindowVisibleDisplayFrame(dim);
Just adding to Francesco's answer. The other observer that is more apt, if you want to find out the location in window or location in screen is ViewTreeObserver.OnPreDrawListener()
This also can be used to find other attributes of a view that is mostly unknown at onCreate() time e.g. the scrolled position, the scaled position.
Using the following code in Activity.
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
int height = metrics.heightPixels;
int wwidth = metrics.widthPixels;
Find width and height of the screen:
width = getWindowManager().getDefaultDisplay().getWidth();
height = getWindowManager().getDefaultDisplay().getHeight();
Using this, we can get the latest and above SDK 13.
// New width and height
int version = android.os.Build.VERSION.SDK_INT;
Log.i("", " name == "+ version);
Display display = getWindowManager().getDefaultDisplay();
int width;
if (version >= 13) {
Point size = new Point();
display.getSize(size);
width = size.x;
Log.i("width", "if =>" +width);
}
else {
width = display.getWidth();
Log.i("width", "else =>" +width);
}
public class AndroidScreenActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
String str_ScreenSize = "The Android Screen is: "
+ dm.widthPixels
+ " x "
+ dm.heightPixels;
TextView mScreenSize = (TextView) findViewById(R.id.strScreenSize);
mScreenSize.setText(str_ScreenSize);
}
}
(2012 answer, may be out of date) If you want to support pre Honeycomb, you will need to put in backward compatibility prior to API 13. Something like:
int measuredWidth = 0;
int measuredHeight = 0;
WindowManager w = getWindowManager();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
Point size = new Point();
w.getDefaultDisplay().getSize(size);
measuredWidth = size.x;
measuredHeight = size.y;
} else {
Display d = w.getDefaultDisplay();
measuredWidth = d.getWidth();
measuredHeight = d.getHeight();
}
Of course the deprecated methods will eventually be taken out of the the most recent SDKs, but while we still rely on most of our users having Android 2.1, 2.2 and 2.3, this is what we are left with.
I have two functions, one for sending the context and the other getting height and width in pixels:
public static int getWidth(Context mContext){
int width=0;
WindowManager wm = (WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
if(Build.VERSION.SDK_INT>12){
Point size = new Point();
display.getSize(size);
width = size.x;
}
else{
width = display.getWidth(); // Deprecated
}
return width;
}
and
public static int getHeight(Context mContext){
int height=0;
WindowManager wm = (WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
if(Build.VERSION.SDK_INT>12){
Point size = new Point();
display.getSize(size);
height = size.y;
}
else{
height = display.getHeight(); // Deprecated
}
return height;
}
First load the XML file and then write this code:
setContentView(R.layout.main);
Display display = getWindowManager().getDefaultDisplay();
final int width = (display.getWidth());
final int height = (display.getHeight());
Show width and height according your screen resolution.
There is a non-deprecated way to do this using DisplayMetrics (API 1), that avoids the try/catch messiness:
// 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;
This is the code I use for the task:
// `activity` is an instance of Activity class.
Display display = activity.getWindowManager().getDefaultDisplay();
Point screen = new Point();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
display.getSize(screen);
} else {
screen.x = display.getWidth();
screen.y = display.getHeight();
}
Seems clean enough and yet, takes care of the deprecation.
Need to say, that if you are not in Activity, but in View (or have variable of View type in your scope), there is not need to use WINDOW_SERVICE. Then you can use at least two ways.
First:
DisplayMetrics dm = yourView.getContext().getResources().getDisplayMetrics();
Second:
DisplayMetrics dm = new DisplayMetrics();
yourView.getDisplay().getMetrics(dm);
All this methods we call here is not deprecated.
I have tried all possible "solutions" unsuccessfully and I noticed that Elliott Hughes' "Dalvik Explorer" app always shows correct dimension on any Android device/OS version. I ended up looking at his open source project that can be found here: https://code.google.com/p/enh/
Here's all the relevant code:
WindowManager w = activity.getWindowManager();
Display d = w.getDefaultDisplay();
DisplayMetrics metrics = new DisplayMetrics();
d.getMetrics(metrics);
// since SDK_INT = 1;
widthPixels = metrics.widthPixels;
heightPixels = metrics.heightPixels;
try {
// used when 17 > SDK_INT >= 14; includes window decorations (statusbar bar/menu bar)
widthPixels = (Integer) Display.class.getMethod("getRawWidth").invoke(d);
heightPixels = (Integer) Display.class.getMethod("getRawHeight").invoke(d);
} catch (Exception ignored) {
}
try {
// used when SDK_INT >= 17; includes window decorations (statusbar bar/menu bar)
Point realSize = new Point();
Display.class.getMethod("getRealSize", Point.class).invoke(d, realSize);
widthPixels = realSize.x;
heightPixels = realSize.y;
} catch (Exception ignored) {
}
EDIT: slightly improved version (avoid firing exceptions on non-supported OS version):
WindowManager w = activity.getWindowManager();
Display d = w.getDefaultDisplay();
DisplayMetrics metrics = new DisplayMetrics();
d.getMetrics(metrics);
// since SDK_INT = 1;
widthPixels = metrics.widthPixels;
heightPixels = metrics.heightPixels;
// includes window decorations (statusbar bar/menu bar)
if (Build.VERSION.SDK_INT >= 14 && Build.VERSION.SDK_INT < 17)
try {
widthPixels = (Integer) Display.class.getMethod("getRawWidth").invoke(d);
heightPixels = (Integer) Display.class.getMethod("getRawHeight").invoke(d);
} catch (Exception ignored) {
}
// includes window decorations (statusbar bar/menu bar)
if (Build.VERSION.SDK_INT >= 17)
try {
Point realSize = new Point();
Display.class.getMethod("getRealSize", Point.class).invoke(d, realSize);
widthPixels = realSize.x;
heightPixels = realSize.y;
} catch (Exception ignored) {
}
I would wrap the getSize code like this:
@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;
}
Isn't this a much better solution? DisplayMetrics comes with everything you need and works from API 1.
public void getScreenInfo(){
DisplayMetrics metrics = new DisplayMetrics();
getActivity().getWindowManager().getDefaultDisplay().getMetrics(metrics);
heightPixels = metrics.heightPixels;
widthPixels = metrics.widthPixels;
density = metrics.density;
densityDpi = metrics.densityDpi;
}
You can also get the actual display (including screen decors, such as Status Bar or software navigation bar) using getRealMetrics, but this works on 17+ only.
Am I missing something?
There are times when you need to know the precise dimensions of the available space for a layout when in an activity's onCreate. After some thought I worked out this way of doing it.
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();
}
}
}
If for some reason you don't want to add another activity to the Android manifest, you can do it this way:
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();
}
}
If you don't want the overhead of WindowManagers, Points, or Displays, you can grab the height and width attributes of the topmost View item in your XML, provided its height and width are set to match_parent. (This is true so long as your layout takes up the entire screen.)
For example, if your XML starts with something like this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/entireLayout"
android:layout_width="match_parent"
android:layout_height="match_parent" >
Then findViewById(R.id.entireLayout).getWidth() will return the screen's width and findViewById(R.id.entireLayout).getHeight() will return the screen's height.
This is not an answer for the OP, as he wanted the display dimensions in real pixels. I wanted the dimensions in "device-independent-pixels", and putting together answers from here https://stackoverflow.com/a/17880012/253938 and here https://stackoverflow.com/a/6656774/253938 I came up with this:
DisplayMetrics displayMetrics = Resources.getSystem().getDisplayMetrics();
int dpHeight = (int)(displayMetrics.heightPixels / displayMetrics.density + 0.5);
int dpWidth = (int)(displayMetrics.widthPixels / displayMetrics.density + 0.5);
For accessing the height of the status bar for Android devices, we prefer a programmatic way to get it:
Sample code
int resId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resId > 0) {
result = getResources().getDimensionPixelSize(resId);
}
The variable result gives the height in the pixel.
For quick access
For more information about height of Title bar, Navigation bar and Content View, kindly look on Android Device Screen Sizes.
For who is searching for usable screen dimension without Status Bar and Action Bar (also thanks to Swapnil's answer):
DisplayMetrics dm = getResources().getDisplayMetrics();
float screen_w = dm.widthPixels;
float screen_h = dm.heightPixels;
int resId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resId > 0) {
screen_h -= getResources().getDimensionPixelSize(resId);
}
TypedValue typedValue = new TypedValue();
if(getTheme().resolveAttribute(android.R.attr.actionBarSize, typedValue, true)){
screen_h -= getResources().getDimensionPixelSize(typedValue.resourceId);
}
I have a splash screen activity with a LinearLayout as a root view that has match_parent for its width & height. This is the code in the onCreate() method of that activity. I use these measures in all other activities of the app.
int displayWidth = getRawDisplayWidthPreHoneycomb();
int rawDisplayHeight = getRawDisplayHeightPreHoneycomb();
int usableDisplayHeight = rawDisplayHeight - getStatusBarHeight();
pf.setScreenParameters(displayWidth, usableDisplayHeight);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
LinearLayout myView = (LinearLayout) findViewById(R.id.splash_view);
myView.addOnLayoutChangeListener(new OnLayoutChangeListener() {
@Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
if (left == 0 && top == 0 && right == 0 && bottom == 0) {
return;
}
int displayWidth = Math.min(right, bottom);
int usableDisplayHeight = Math.max(right, bottom);
pf.setScreenParameters(displayWidth, usableDisplayHeight);
}
});
}
Here are the implementations for the methods you see get called above:
private int getRawDisplayWidthPreHoneycomb() {
WindowManager windowManager = getWindowManager();
Display display = windowManager.getDefaultDisplay();
DisplayMetrics displayMetrics = new DisplayMetrics();
display.getMetrics(displayMetrics);
int widthPixels = displayMetrics.widthPixels;
int heightPixels = displayMetrics.heightPixels;
return Math.min(widthPixels, heightPixels);
}
private int getRawDisplayHeightPreHoneycomb() {
WindowManager w = getWindowManager();
Display d = w.getDefaultDisplay();
DisplayMetrics metrics = new DisplayMetrics();
d.getMetrics(metrics);
int widthPixels = metrics.widthPixels;
int heightPixels = metrics.heightPixels;
return Math.max(widthPixels, heightPixels);
}
public int getStatusBarHeight() {
int statusBarHeight = 0;
int resourceId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resourceId > 0) {
statusBarHeight = getResources().getDimensionPixelSize(resourceId);
}
return statusBarHeight;
}
This results in the height and width of the usable display, excluding any type of bars (status bar, navigation bar), for all API versions and different types of devices (phones and tablets).
Follow the methods below:
public static int getWidthScreen(Context context) {
return getDisplayMetrics(context).widthPixels;
}
public static int getHeightScreen(Context context) {
return getDisplayMetrics(context).heightPixels;
}
private static DisplayMetrics getDisplayMetrics(Context context) {
DisplayMetrics displayMetrics = new DisplayMetrics();
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
wm.getDefaultDisplay().getMetrics(displayMetrics);
return displayMetrics;
}
DisplayMetrics dimension = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dimension);
int w = dimension.widthPixels;
int h = dimension.heightPixels;
Simplest way:
int screenHeight = getResources().getDisplayMetrics().heightPixels;
int screenWidth = getResources().getDisplayMetrics().widthPixels;
For getting the screen dimensions use display metrices
DisplayMetrics displayMetrics = new DisplayMetrics();
if (context != null)
WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display defaultDisplay = windowManager.getDefaultDisplay();
defaultDisplay.getRealMetrics(displayMetrics);
}
Get the height and width in pixels
int width =displayMetrics.widthPixels;
int height =displayMetrics.heightPixels;
You can do get the height size using :
getResources().getDisplayMetrics().heightPixels;
and the width size using
getResources().getDisplayMetrics().widthPixels;