EDIT: The application's interface
I've created a Pop-up window and class that when I click this onInfoWindowClick in the google maps, a pop-up window will appear OR the next activity will appear. I used Display Metrics for this but it only shows up in the center screen.
What I want to happen is: when the activity shows up, I would like it to show up in the upper-top or at least have the power to change the position of the activity in any part of the window.
My problem: The display metrics shows the activity only in the center.
My codes in my Pop-Up window:
public class PopUp extends AppCompatActivity {
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.pop_layout);
DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
int width = dm.widthPixels;
int height = dm.heightPixels;
getWindow().setLayout((int)(width*.8),(int)(height*.5));
}
}
Note: Is there an another method to do this? Can you give me link on how to do it. (Only if there is an another method to do it)
Just add this line at the end:
getWindow().setGravity(Gravity.TOP);
P.S. you can use other values (not only Gravity.TOP) according to your needs. Also you can combine multiple options, for instance, getWindow().setGravity(Gravity.TOP|Gravity.START);
I have a very simple RelativeLayout subclass that adds an image view with a text view on top of it. I have a method, show(), which creates and adds the child views and sets the initial text.
At the point I call show() for the first time, the view does not know how big it is, so I can't set the textSize nor the padding for the textView.
I have a solution that mostly works, where I call setTextSize() and setPadding() for the textView within the overridden method, onSizeChanged(). The text does not show the first time it is displayed. However, it shows every time after that, perfectly sized and placed.
Here is the code for onSizeChanged():
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
Log.e(TAG, "onSizeChanged() called");
if (_childTextView != null) {
float textSize = h / 2.0f;
int topPadding = (int)(h / 3.0f);
Log.e(TAG, "setting textSize = " + textSize);
Log.e(TAG, "topPadding = " + topPadding);
_childTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize);
_childTextView.setPadding(0, topPadding, 0, 0);
}
super.onSizeChanged(w, h, oldw, oldh);
Log.e(TAG, "end onSizeChanged()");
}
The code for show() is as follows:
public void show(int val) {
_val = val;
Log.e(TAG, "in show(), val = " + val);
// create and add background image if not already there
if (_backgroundImageView == null) {
_backgroundImageView = new ImageView(_context);
_backgroundImageView.setImageResource(R.drawable.background);
LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
params.addRule(CENTER_IN_PARENT);
addView(_backgroundImageView, params);
}
// create and add text view if not already there
if (_childTextView == null) {
_childTextView = new TextView(_context);
_childTextView.setTextColor(Color.BLACK);
LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.addRule(CENTER_HORIZONTAL);
addView(_childTextView, params);
}
Log.e(TAG, "setting text to: " + _val);
// update value and make visible
_childTextView.setText(String.valueOf(_val));
setVisibility(VISIBLE);
Log.e(TAG, "end show()");
}
The background image displays correctly every time. The textView only displays correctly the second time show() is called and afterwards. Logging in onSizeChanged() shows that the calculated numbers are correct the first time. As expected, onSizeChanged() only gets called the first time, a bit after we return from show(). Subsequent calls to show() just set the value and visibility, and the text is displayed correctly.
My question is: is there a better way to do this? Or a better callback method to override?
Trying to set these values in show() doesn't work because the main view doesn't yet know its own size (at least the first time). I have tried putting invalidate() at the end of onSizeChanged(). I have also tried putting the call to setText() there.
I need to be able to do this based on size, because this class is reused in different contexts where the image needs to be smaller or larger.
Thank you for any insight you can give. I'd really like to keep this simple if possible.
Edit: What I am trying to do is size some text to be about 1/2 the size of the child image (which is the same as the parent size), and to have top padding set to about 1/3 of the image size. This would be easy if I just wanted it to be one size. However, I want it to be size-adjustable based on the needs of the display.
Imagine a postage stamp, where you want to place the value somewhere precisely in the image. So far so good. But what if this postage stamp needs to be displayed at different sizes on the same phone? You'd want both the placement offset (the padding) and the text size to adjust accordingly. If I hardcode this into the xml, then the text size and placement will not be adjusted when I size the layout. The text will be too big on the small version, and will be placed too far from the top of the image.
i have no idea why you override onSizeChanged(), normaly android handles all this nicely if you use it the way it is intendet.
can you pls explain what you want to achive - maybe with example picture?
however i wondered that you don't override onMesure() when you override the rest and if a delayed call to show() helps it also might be because of onMesure is called in between.
edit:
in android you should never want to know a real size of some views. nearly every device has other sizes and there is portrait/landscape mode too. if you start coding vs real sizes you can give up at the start. instead you should use something more relative like dp and sp than you should never again worry about text sizes and similar.
you may also want and you should use LayoutInflater and xml files as much as possible in your application. in a Activity you can call setContentView(). in other cases there might be methods to overload like onCreateView. and if you have nothing else you can do it like this:
LayoutInflater inflater = LayoutInflater.from(contextEgActivity);
View rootView = inflater.inflate(R.layout.highscore_daily, parentCanBeNull);
edit II:
so this is what you want - right? (on the ImageView and the TextView it would be even better to use wrap_content for height and width)
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:layout_width="200dp"
android:layout_height="200dp"
android:id="#+id/imageView"
android:layout_gravity="center"
android:background="#ff0000" />
<TextView
android:layout_width="100dp"
android:layout_height="100dp"
android:text="New Text"
android:id="#+id/textView"
android:layout_gravity="center"
android:background="#00ff00"
android:textSize="20sp" />
</FrameLayout>
if you only have ~3 different sizes i would write 3 different xml files to match what you want. otherwise i think this code will fit your needs.
//http://stackoverflow.com/questions/4605527/converting-pixels-to-dp
public static float convertDpToPixel(float dp, Context context){
Resources resources = context.getResources();
DisplayMetrics metrics = resources.getDisplayMetrics();
float px = dp * (metrics.densityDpi / 160f);
return px;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);//loads the xml above
ImageView v = (ImageView) findViewById(R.id.imageView);
int dp = 200;
int px = (int) convertDpToPixel(dp, this);
v.setMaxHeight(px);//no need for it
v.setMinimumHeight(px);//should do more or less the same as next line
v.setLayoutParams(new LinearLayout.LayoutParams(px, px));//is like android:layout_width="200dp" android:layout_height="200dp"
v.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, px));//is like android:layout_width="wrap_content" android:layout_height="200dp"
//basically you can do the same with the TextView + the Text styling
TextView tv = (TextView) findViewById(R.id.textView);
tv.setTextSize(TypedValue.COMPLEX_UNIT_SP, 50);
tv.setPadding(30,30,30,30);//don't forget, this is also px so you may need dp to px conversion
}
this is the normal way, nice clean and easy. if you why ever still want to react on size changes of your parent you can try this but i don't suggest it. btw changing view stuff should only be executed from ui/main thread so if the method gets called from a other thread thry a Handler like new Handler(getMainLooper)
I'm looking for a good way to measure the dimensions of the actual content area for an activity in Android.
Getting display always works. Simply go like this:
Display display = getWindowManager().getDefaultDisplay();
And you can get the pixel count for the entire screen. Of course this does not take into consideration the ActionBar, status bar, or any other views which will reduce the available size of the activity itself.
Once the activity is running, you can do this:
View content = getWindow().findViewById(Window.ID_ANDROID_CONTENT);
To get the activity content only. But doing this in onCreate() will result in a view with width and height of 0, 0.
Is there a way to get these dimensions during onCreate? I imagine there ought to be a way to get the measurements of any status bars and just subtract that from the total display size, but I'm unable to find a way to do that. I think this would be the only way, because the content window method will always return a view with no width/height before it is drawn.
Thanks!
You can use a layout or pre-draw listener for this, depending on your goals. For example, in onCreate():
final View content = findViewById(android.R.id.content);
content.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
//Remove it here unless you want to get this callback for EVERY
//layout pass, which can get you into infinite loops if you ever
//modify the layout from within this method.
content.getViewTreeObserver().removeGlobalOnLayoutListener(this);
//Now you can get the width and height from content
}
});
Update
as of API 16 removeGlobalOnLayoutListener is deprecated.
Change to:
content.getViewTreeObserver().removeOnGlobalLayoutListener(this)
(copied from my answer to a related question)
I use the following technique - post a runnable from onCreate() that will be executed when the view has been created:
contentView = findViewById(android.R.id.content);
contentView.post(new Runnable()
{
public void run()
{
contentHeight = contentView.getHeight();
}
});
This code will run on the main UI thread, after onCreate() has finished.
Answer with post is incorrect, because the size might not be recalculated.
Another important thing is that the view and all it ancestors must be visible. For that I use a property View.isShown.
Here is my kotlin function, that can be placed somewhere in utils:
fun View.onInitialized(onInit: () -> Unit) {
viewTreeObserver.addOnGlobalLayoutListener(object : OnGlobalLayoutListener {
override fun onGlobalLayout() {
if (isShown) {
viewTreeObserver.removeOnGlobalLayoutListener(this)
onInit()
}
}
})
}
And the usage is:
myView.onInitialized {
Log.d(TAG, "width is: " + myView.width)
}
This appears to be a duplicate question. There is an elegant answer within this SO question:
getWidth() and getHeight() of View returns 0
Which (shamelessly copied) is to override onWindowFocusChanged(), which seems to fire just after onCreate(), and where the sizes are rendered:
#Override
public void onWindowFocusChanged(boolean hasFocus) {
super.onWindowFocusChanged(hasFocus);
//Here you can get the size!
}
If you want lo load a Bitmap into a ImageView within OnCreate(), you can use this example to do it:
public static void setImageLater(#NonNull final ImageView imageView,final Bitmap bitmap){
final ViewTreeObserver observer = imageView.getViewTreeObserver();
observer.addOnGlobalLayoutListener(
new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
imageView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
imageView.setImageBitmap(bitmap);
}
});
}
You can do any work wich needs sizes in onResume(using flag like alreadyDone not to repeat it every time an Activity goes foreground). In onCreate views are not displayed, so it's normal that sizes are zeros.
I am developing an android app in which I need to display the saved gesture to the user. I have tried doing it using the GestureOverlayView object's setGesture() function but it displays the gesture well outside the screen. Only small portion is visible in the left top corner of the screen in the Android emulator 2.1.
Here is the code that I have used..
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.savegesture);
gestureoverlay = (GestureOverlayView) findViewById(R.id.gestures_overlay2);
mOldGesture = (Gesture) getIntent().getExtras().get("gesture");
mDoneButton = findViewById(R.id.done);
DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
gestureoverlay.setLayoutParams(new FrameLayout.LayoutParams(dm.widthPixels,dm.heightPixels,0x50));
gestureoverlay.setGesture(mOldGesture);
gestureoverlay.invalidate();
}
The android GestureOverlayView defined in "savegesture.xml" is as follows:-
<android.gesture.GestureOverlayView android:scaleType="center" android:layout_gravity="center"
android:id="#+id/gestures_overlay2" android:layout_width="fill_parent"
android:layout_height="fill_parent" android:gestureStrokeType="multiple" />
I don't know what the problem is, but it won't show the gesture ON the screen....
Although this is a 3 year old question, I'll still add an answer.
The gesture appears outside the GestureOverlayView because it's been set in onCreate. It must be set after the layout measurements have been computed.
ViewTreeObserver can be used to know when the layout has been measured.
ViewTreeObserver vto = gestureoverlay.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
gestureoverlay.getViewTreeObserver().removeGlobalOnLayoutListener(this);
gestureoverlay.setGesture(mOldGesture);
}
});
Altough this is a 5 year old question, I'll still add an answer, because the approved answer is inefficient in comparison to this:
Use view.post() to execute code after the view has been loaded.
gestureoverlay.post(new Runnable() {
#Override
public void run() {
gestureoverlay.setGesture(mOldGesture);
}
});
I have a view made up of TableLayout, TableRow and TextView. I want it to look like a grid. I need to get the height and width of this grid. The methods getHeight() and getWidth() always return 0. This happens when I format the grid dynamically and also when I use an XML version.
How to retrieve the dimensions for a view?
Here is my test program I used in Debug to check the results:
import android.app.Activity;
import android.os.Bundle;
import android.widget.TableLayout;
import android.widget.TextView;
public class appwig extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.maindemo); //<- includes the grid called "board"
int vh = 0;
int vw = 0;
//Test-1 used the xml layout (which is displayed on the screen):
TableLayout tl = (TableLayout) findViewById(R.id.board);
tl = (TableLayout) findViewById(R.id.board);
vh = tl.getHeight(); //<- getHeight returned 0, Why?
vw = tl.getWidth(); //<- getWidth returned 0, Why?
//Test-2 used a simple dynamically generated view:
TextView tv = new TextView(this);
tv.setHeight(20);
tv.setWidth(20);
vh = tv.getHeight(); //<- getHeight returned 0, Why?
vw = tv.getWidth(); //<- getWidth returned 0, Why?
} //eof method
} //eof class
I believe the OP is long gone, but in case this answer is able to help future searchers, I thought I'd post a solution that I have found. I have added this code into my onCreate() method:
EDITED: 07/05/11 to include code from comments:
final TextView tv = (TextView)findViewById(R.id.image_test);
ViewTreeObserver vto = tv.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
LayerDrawable ld = (LayerDrawable)tv.getBackground();
ld.setLayerInset(1, 0, tv.getHeight() / 2, 0, 0);
ViewTreeObserver obs = tv.getViewTreeObserver();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
obs.removeOnGlobalLayoutListener(this);
} else {
obs.removeGlobalOnLayoutListener(this);
}
}
});
First I get a final reference to my TextView (to access in the onGlobalLayout() method). Next, I get the ViewTreeObserver from my TextView, and add an OnGlobalLayoutListener, overriding onGLobalLayout (there does not seem to be a superclass method to invoke here...) and adding my code which requires knowing the measurements of the view into this listener. All works as expected for me, so I hope that this is able to help.
I'll just add an alternative solution, override your activity's onWindowFocusChanged method and you will be able to get the values of getHeight(), getWidth() from there.
#Override
public void onWindowFocusChanged (boolean hasFocus) {
// the height will be set at this point
int height = myEverySoTallView.getMeasuredHeight();
}
You are trying to get width and height of an elements, that weren't drawn yet.
If you use debug and stop at some point, you'll see, that your device screen is still empty, that's because your elements weren't drawn yet, so you can't get width and height of something, that doesn't yet exist.
And, I might be wrong, but setWidth() is not always respected, Layout lays out it's children and decides how to measure them (calling child.measure()), so If you set setWidth(), you are not guaranteed to get this width after element will be drawn.
What you need, is to use getMeasuredWidth() (the most recent measure of your View) somewhere after the view was actually drawn.
Look into Activity lifecycle for finding the best moment.
http://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle
I believe a good practice is to use OnGlobalLayoutListener like this:
yourView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
if (!mMeasured) {
// Here your view is already layed out and measured for the first time
mMeasured = true; // Some optional flag to mark, that we already got the sizes
}
}
});
You can place this code directly in onCreate(), and it will be invoked when views will be laid out.
Use the View's post method like this
post(new Runnable() {
#Override
public void run() {
Log.d(TAG, "width " + MyView.this.getMeasuredWidth());
}
});
I tried to use onGlobalLayout() to do some custom formatting of a TextView, but as #George Bailey noticed, onGlobalLayout() is indeed called twice: once on the initial layout path, and second time after modifying the text.
View.onSizeChanged() works better for me because if I modify the text there, the method is called only once (during the layout pass). This required sub-classing of TextView, but on API Level 11+ View. addOnLayoutChangeListener() can be used to avoid sub-classing.
One more thing, in order to get correct width of the view in View.onSizeChanged(), the layout_width should be set to match_parent, not wrap_content.
Are you trying to get sizes in a constructor, or any other method that is run BEFORE you get the actual picture?
You won't be getting any dimensions before all components are actually measured (since your xml doesn't know about your display size, parents positions and whatever)
Try getting values after onSizeChanged() (though it can be called with zero), or just simply waiting when you'll get an actual image.
As F.X. mentioned, you can use an OnLayoutChangeListener to the view that you want to track itself
view.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
#Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
// Make changes
}
});
You can remove the listener in the callback if you only want the initial layout.
I guess this is what you need to look at: use onSizeChanged() of your view. Here is an EXTENDED code snippet on how to use onSizeChanged() to get your layout's or view's height and width dynamically http://syedrakibalhasan.blogspot.com/2011/02/how-to-get-width-and-height-dimensions.html
ViewTreeObserver and onWindowFocusChanged() are not so necessary at all.
If you inflate the TextView as layout and/or put some content in it and set LayoutParams then you can use getMeasuredHeight() and getMeasuredWidth().
BUT you have to be careful with LinearLayouts (maybe also other ViewGroups). The issue there is, that you can get the width and height after onWindowFocusChanged() but if you try to add some views in it, then you can't get that information until everything have been drawn. I was trying to add multiple TextViews to LinearLayouts to mimic a FlowLayout (wrapping style) and so couldn't use Listeners. Once the process is started, it should continue synchronously. So in such case, you might want to keep the width in a variable to use it later, as during adding views to layout, you might need it.
Even though the proposed solution works, it might not be the best solution for every case because based on the documentation for ViewTreeObserver.OnGlobalLayoutListener
Interface definition for a callback to be invoked when the global layout state or the visibility of views within the view tree changes.
which means it gets called many times and not always the view is measured (it has its height and width determined)
An alternative is to use ViewTreeObserver.OnPreDrawListener which gets called only when the view is ready to be drawn and has all of its measurements.
final TextView tv = (TextView)findViewById(R.id.image_test);
ViewTreeObserver vto = tv.getViewTreeObserver();
vto.addOnPreDrawListener(new OnPreDrawListener() {
#Override
public void onPreDraw() {
tv.getViewTreeObserver().removeOnPreDrawListener(this);
// Your view will have valid height and width at this point
tv.getHeight();
tv.getWidth();
}
});
Height and width are zero because view has not been created by the time you are requesting it's height and width . One simplest solution is
view.post(new Runnable() {
#Override
public void run() {
view.getHeight(); //height is ready
view.getWidth(); //width is ready
}
});
This method is good as compared to other methods as it is short and crisp.
You should rather look at View lifecycle: http://developer.android.com/reference/android/view/View.html Generally you should not know width and height for sure until your activity comes to onResume state.
You can use a broadcast that is called in OnResume ()
For example:
int vh = 0;
int vw = 0;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.maindemo); //<- includes the grid called "board"
registerReceiver(new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
TableLayout tl = (TableLayout) findViewById(R.id.board);
tl = (TableLayout) findViewById(R.id.board);
vh = tl.getHeight();
vw = tl.getWidth();
}
}, new IntentFilter("Test"));
}
protected void onResume() {
super.onResume();
Intent it = new Intent("Test");
sendBroadcast(it);
}
You can not get the height of a view in OnCreate (), onStart (), or even in onResume () for the reason that kcoppock responded
Simple Response: This worked for me with no Problem.
It seems the key is to ensure that the View has focus before you getHeight etc. Do this by using the hasFocus() method, then using getHeight() method in that order. Just 3 lines of code required.
ImageButton myImageButton1 =(ImageButton)findViewById(R.id.imageButton1);
myImageButton1.hasFocus();
int myButtonHeight = myImageButton1.getHeight();
Log.d("Button Height: ", ""+myButtonHeight );//Not required
Hope it helps.
Use getMeasuredWidth() and getMeasuredHeight() for your view.
Developer guide: View
CORRECTION:
I found out that the above solution is terrible. Especially when your phone is slow.
And here, I found another solution:
calculate out the px value of the element, including the margins and paddings:
dp to px:
https://stackoverflow.com/a/6327095/1982712
or dimens.xml to px:
https://stackoverflow.com/a/16276351/1982712
sp to px:
https://stackoverflow.com/a/9219417/1982712 (reverse the solution)
or dimens to px:
https://stackoverflow.com/a/16276351/1982712
and that's it.