If I call getMeasuredWidth() or getWidth() for layout in onResume they return 0
If I call getMeasuredWidth() or getWidth() for layout in onResume they returns 0. I think that view it's not drawn yet in this moment.
Also I think that I need to put getMeasuredWidth() or ge开发者_JAVA百科tWidth() in callback method called after layout is drawn and view measurements are known. What android callback method should I use?
You cannot use the width
/height
/getMeasuredWidth
/getMeasuredHeight
on a View
before the system renders it (typically from onCreate
/onResume
).
Simple solution for this is to post a Runnable
to the layout. The runnable will be executed after the View
has been laid out.
BoxesLayout = (RelativeLayout) findViewById(R.id.BoxesLinearLayout);
BoxesLayout.post(new Runnable() {
@Override
public void run() {
int w = BoxesLayout.getMeasuredWidth();
int h = BoxesLayout.getMeasuredHeight();
...
}
});
This answer says:
Use the ViewTreeObserver
on the View
to wait for the first layout. Only after the first layout will getWidth()/getHeight()/getMeasuredWidth()/getMeasuredHeight()
work.
ViewTreeObserver viewTreeObserver = view.getViewTreeObserver();
if (viewTreeObserver.isAlive()) {
viewTreeObserver.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
view.getViewTreeObserver().removeGlobalOnLayoutListener(this);
viewWidth = mediaGallery.getWidth();
viewHeight = mediaGallery.getHeight();
}
});
}
you can override onLayout() in your view; this is used by android to position each of the children the view has, so you could do the stuff you want to do there after the super(..)
call.
Indeed, it appears that if the layout is not shown on the screen the getWidth() method returns 0. What seems to work for me is calling the measure() method before calling the getMeasuredWidth() or getMesuredHeight(). For the measure method I used the Layout.WRAP_CONTENT arguments to get a measurement of what the layout contains.
Hope this helps, Mihai
Simpler way:
view.post(new Runnable() {
public void run() {
view.getWidth();
}
}
);
http://developer.android.com/reference/android/view/View.html#post(java.lang.Runnable)
Solution #1: To do it dynamically, you need a tag. A tag is basically a way for views to have memories. So save the convertView in another class (MyTag). So inside your java file:
private LayoutInflater layoutInflater;
@Override
public View getView(int position, View convertView, ViewGroup parent) {
MyTag holder = null;
View row = convertView;
if (row == null) {
//Inflate the view however u can
String strInflater = Context.LAYOUT_INFLATER_SERVICE;
layoutInflater = (LayoutInflater) context.getSystemService(strInflater);
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
row = inflater.inflate(layoutResID, parent, false);
holder = new MyTag();
holder.itemName = (TextView) row.findViewById(R.id.example_itemname);
holder.icon = (ImageView) row.findViewById(R.id.example_image);
holder.button1 = (Button) row.findViewById(R.id.swipe_button1);
holder.button2 = (Button) row.findViewById(R.id.swipe_button2);
holder.button3 = (Button) row.findViewById(R.id.swipe_button3);
row.setTag(holder);
} else {
holder = (MyTag) row.getTag();
}
holder.itemName.setText(itemdata.getItemName());
System.out.println("holder.button3.getMeasuredWidth()= "+ holder.button3.getMeasuredWidth());
System.out.println("holder.button3.getWidth()= "+ holder.button3.getWidth());
return row;
} //End of getView()
static class MyTag { //It also works if not static
TextView itemName;
ImageView icon;
Button button1;
Button button2;
Button button3;
}
Solution #2: Hard-code it. Pre-set the width. Inside your res/values/dimens.xml file, include
<dimen name="your_button_width">50dp</dimen>
Then inside your res/layout/your_layout.xml file, include
<Button
android:layout_width="@dimen/your_button_width" />
Then inside your java file:
int buttonSize= (int) (context.getResources().getDimension(R.dimen.your_button_width));
Use below code:
@Override
public void onWindowFocusChanged(boolean hasFocus) {
super.onWindowFocusChanged(hasFocus);
Log.e("WIDTH",""+view.getWidth());
Log.e("HEIGHT",""+view.getHeight());
}
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