Develop Reference

android , moving view in linearlayout

I made a linear layout and it contain some Image views . when i move one with (set X(view.get x + 10)) function, it moves... but it moves behind other views. that the view become hidden.
and the other problem is when i get X & Y of the view, its always 0,0. but the view is in the middle of the screen. what should I do??? should i give up with linear layout??
if(wichmov == "right" ){
if(martin.getX() < width){
martin.setX(martin.getX()+ deltax);
}
else if(wichmov == "left"){
if(martin.getX() > 0){
martin.setX(martin.getX()- deltax );
}
}
}
this is how i move it.

When are you trying to call getX()? This might be something to look into: View getX() and getY() return 0.0 after they have been added to the Activity
If you're making the call in onCreate, it'll be zero.

I just figured it out.
I use a relative layout and then set the linear layout as match parent. After designing the background with the linear layout, I define an image view after the linear layout and inside of the relative layout, and then in Java, I set the position of it in the exact place I want it to (front of the special box of linear layout that I wanted it move), and width and height of it too.
The following code will help you to place your view to the exact place of your screen you want it, and set its width and height:
DisplayMetrics metrics = this.getResources().getDisplayMetrics(); //getting screen size
width = metrics.widthPixels;
height = metrics.heightPixels;
view.setX(width *5/8); //setting the place
view.setY(height/4);
LayoutParams para = view.getLayoutParams(); //set size of view
para.height = (int) (height/2);
para.width = (int) (width/4);
view.setLayoutParams(para);

Android: how to determine new size of a view

I have a LinearLayout (vertical) with two child views in it. The 1st one is a ScrollView and the 2nd one is another layout with Visibility.GONE, its size is not fixed (determined by its children).
<LinearLayout vertical>
<ScrollView> ... </ScrollView>
<AnotherLayout visibility=GONE height=wrap_content> ... </AnotherLayout>
</LinearLayout>
At some point of time I want to show AnotherLayout. But, once it pops up, I also want to adjust the scrolling of my ScollView one. For this, I need to know the size of this AnotherLayout.
I'm doing something like that:
int oldHeight = scrollArea.getHeight();
linearLayout.setVisibility(VISIBLE);
int newHeight = scrollArea.getHeight();
But oldHeight and newHeight are still the same.
How can I calculate the new height?

The two dimensions are the same because visibility change took time and the line of code was run before that so it returns the same.
You can use a visibility listener to calculate the dimension after visibility change , You may use that
linearLayout.setTag(linearLayout.getVisibility());
linearLayout.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
int newVis = linearLayout.getVisibility();
if((int)linearLayout.getTag() != newVis)
{
linearLayout.setTag(linearLayout.getVisibility());
//visibility has changed
int newHeight = scrollArea.getHeight();
}
}
});

Set Views Y position programmatically

I got a layout in which there's a RelativeLayout with a visibility of GONE. This rl is a layout for a bar with buttons which appears at the bottom of the fragment when setting the visibility to visible. While the RL is still not visible, there are 2 buttons and when I set it to visible, the RL is covering the buttons.
What I want to do is simply move the buttons up above that bar which becomes visible. What I tried to do it:
rl.setVisibility(View.VISIBLE);
rl.post(new Runnable()
{
int dpToPx(final int dp)
{
return (int) (dp * getResources().getSystem().getDisplayMetrics().density + 0.5f);
}
#Override
public void run() {
int h = rl.getHeight(); //height is ready
h = dpToPx(h);
ImageButton button = (ImageButton)inflate.findViewById(R.id.button1);
float y = button.getY();
button.setY((float)h+y - 1100);
ImageButton button2 = (ImageButton)inflate.findViewById(R.id.button2);
y = button2.getY();
button2.setY((float)h+y);
}
});
The button with the -1100 (That number was just something I checked to see how it affects the position of the button and will not stay there obviously) is showing where I want it to be. The other button is so high or low which is no longer visible.
How do I set the position such that the button's Y position will be the old position + the height of the newly shown relative layout so the buttons will show just above it?

This is straightforward, all we need to do is to position the buttons at the y coordinate of our RelativeLayout.
We can get the y coordinate by calling:
rl.getY();
And since we want the button to be above the rl, we will subtract its height from the y coordinate of rl, something like this:
button.setY(rl.getY() - button.getHeight());

Android TextView: can I stop text that is partially displayed from appearing

In my app I display several text views containing text of various length that is loaded in at run time. I do not know the dimensions of the text view or the length of the text until run time. Sometimes, when the text is long and the textview small some of the text is partially visible, for example:
I want to remove the partially visible text as it looks a bit naff, but I can't find a way to do this. Any help would be appreciated!
Thanks,
Dave

You can hard code the TextView height in a way that the second row of text will not be visible.
Or use:
android:maxLines , Makes the TextView be at most this many lines tall.
as suggested above.

Put your textviews in a scrollview layout.And specify a specific width to your textview and make the height wrap content.So that your text doesn't get cut.

This is how I did it. I ran this code after the activity had loaded by posting the method CheckTextIsVisible to the parent relativelayout's handler queue, otherwise the height of the textviews will not be known:
m_eventsLayout.Post(new Action(CheckTextIsVisible));
Then the method CheckTextIsVisible finds each textview with text in it, calculates the height of the font, works out how many lines can fit in the textview, and sets the number of maximum lines accordingly:
private void CheckTextIsVisible()
{
View view;
TextView tView;
Android.Text.TextPaint tPaint;
float height;
int heightOfTextView;
int noLinesInTextView;
for (int i = 0; i < m_eventsLayout.ChildCount; i++)
{
view = m_eventsLayout.GetChildAt(i);
if (view is TextView)
{
tView = (TextView)view;
if (tView.Text != "")
{
//calculate font height
tPaint = tView.Paint;
height = CalculateTextHeight(tPaint.GetFontMetrics());
//calculate the no of lines that will fit in the text box based on this height
heightOfTextView = tView.Height;
noLinesInTextView = (int)(heightOfTextView / height);
//set max lines to this
tView.SetMaxLines(noLinesInTextView);
}
}
}
}
private float CalculateTextHeight(Android.Graphics.Paint.FontMetrics fm)
{
return fm.Bottom - fm.Top;
}
This results in no partially visible text!

Get itemPosition in the layout (x and y parametres)

I have a RelativeLayout in which i have one ImageButton.
I need the position parametres of this item and I don,t know how to get them.
I have try with:
ImageButton user = (ImageButton) findViewById(R.id.User);
int x =user.getTop();
int y =user.getLeft();
But the result is allways 0;
Thank you.

I think you are invoking this method when the layout is being drawn, instead you should use:
ViewTreeObserver observer = user.getViewTreeObserver();
observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
//in here, place the code that requires you to know the dimensions.
//Place your code here
}
}

getTop() and getLeft() returns you the location of the view relative to its parent. For instance, when getLeft() returns 20, that means the view is located 20 pixels to the right of the left edge of its direct parent. See here under the point position. Try something like:
user.getParent().getLeft();
hope that helps!

Because your ImageButton was not calculated its position ready on that time.
see How to get an Android widget's size after layout is calculated?
Do not try to get position in onCreate(), that always returns 0.