Automatic height in blocks (in WebView, ListView etc.)

Patryk_F · February 28, 2020, 5:41pm

Hello. How to set the automatic height of an element in blocks? I tried 0 and -1. -1 sets Fill Parent, and 0 causes the element to disappear.

ewpatton · February 28, 2020, 5:45pm

Automatic height is -1. Fill parent is -2. In the case of WebViewer, it interprets Automatic as Fill Parent, but for every other component it will try to only take up as much space as it needs.

Patryk_F · February 28, 2020, 5:57pm

I’m using the ListView element. When I set the automatic height in Designer is ok. When I set the height in Blocks to -1, it extends the ListView to the entire screen. I returned the ListView height to the text label and after starting the application when ListView has an automatic height in the label shows me the value 0.

Patryk_F · February 29, 2020, 7:22pm

Is this how it works in ListView? Is this a error?

TIMAI2 · February 29, 2020, 7:44pm

I have to agree with Patryk_F. After testing (in companion) if a listview is on the screen, setting a listview to height = -1 with blocks set the listview to fill parent.

ewpatton · March 2, 2020, 6:03pm

Actually, it looks like this logic also applies to ListView:

github.com

mit-cml/appinventor-sources/blob/127c96111782483f32ac7ae3272f47c2f2349f3a/appinventor/components/src/com/google/appinventor/components/runtime/ListView.java#L178


}


/**
* Specifies the `%type%`'s vertical height, measured in pixels.
* @param height for height length
*/
@Override
@SimpleProperty(description = "Determines the height of the list on the view.",
    category =PropertyCategory.APPEARANCE)
public void Height(int height) {
  if (height == LENGTH_PREFERRED) {
    height = LENGTH_FILL_PARENT;
  }
  super.Height(height);
}


/**
* Specifies the horizontal width of the `%type%`, measured in pixels.
* @param width for width length
*/
@Override

yosi · April 21, 2024, 9:19pm

Hi,
Did you found a solution ?

yosi · April 21, 2024, 8:50pm

Hi everyone,
I tried to set listview height to automatic from the blocks so I tried to set the height to -1 but it set it to fill parent. what can I do? please help me

Anke · April 21, 2024, 9:04pm

Android or iOS? Post the aia.

yosi · April 21, 2024, 9:17pm

Android,

the block is setting the listview to fill parent and not to automatic.
I think is a bug

yosi · April 21, 2024, 9:37pm

Do you have idea?

TIMAI2 · April 21, 2024, 9:58pm

You can workaround by doing something like this, using combinations of these blocks:

If you change the number of entries, you will need to set the listview height to 0 then load the elements again.