Feature request: add optional scroll to the TextInput widget [$34]

[ghost]

The TextInput widget needs a scrollbar / scroll capability on x, y axis when the text overflows in it.

If one attaches TextInput to ScrollView like this, the TextInput object will be scrolled, moved around, not the actual text in the widget:

ScrollView:
    id: scrlv
    TextInput:
        text: disp_text
        size_hint: 1, None
        height: max( (len(self._lines)+1) * self.line_height, scrlv.height)

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[tito]

From master, the corresponding Kv would be:

ScrollView:
    TextInput:
        size_hint_y: None
        height: self.minimum_height

As many others widgets, if you want a textinput with a scrollbar, just make the assembly as showed in the kv. That's not more complex than that. It would be complex if we start to mix behavior for your own need.

The kivy way is not to make all the widgets complex and hard to maintain, but cut into small and reusable piece.

[tshirtman]

I disagree, there are good reasons for which the TextInput should control its scrolling, the visibility of the cursor is one of them, when you go up/down, you want moving the cursor to control the scrolling, and you want the view to go back to cursor when you start typing. Currently the TextInput can scroll when the text is larger than the container, but there is no scrollbar to it, and no touch management, only keyboard can control it, if you put the TextInput in a ScrollView, then you lose the keyboard-controlled scrolling, and the sync between cursor position and view.

[tito]

Ok, +1.

[ghost]

Thanks tito for reopening it, using your code gives me a textinput that changes it's size and the widget scrolls up and down, not the text, it's the same as the code posted by me.

[ndapost]

py:

  class Root(BoxLayout):
       def change_scroll_y(self, ti, scrlv):
             y_cursor = ti.cursor_pos[1]
             y_bar = scrlv.scroll_y * (ti.height-scrlv.height)
             if ti.height > scrlv.height:
                    if y_cursor >= y_bar + scrlv.height:
                            dy = y_cursor - (y_bar + scrlv.height)
                            scrlv.scroll_y = scrlv.scroll_y + scrlv.convert_distance_to_scroll(0, dy)[1] 
                    if y_cursor - ti.line_height <= y_bar:
                            dy = (y_cursor - ti.line_height) - y_bar
                            scrlv.scroll_y = scrlv.scroll_y + scrlv.convert_distance_to_scroll(0, dy)[1] 

kv:

Root:    
    ScrollView:
        id: scrlv
        bar_width: 10
        scroll_type: ['bars', 'content']
        size_hint: 0.2, 0.2
        bar_inactive_color: self.bar_color        
    TextInput:
        id: ti
        font_size: 23
        size_hint: 1, None
        height: max(self.minimum_height, scrlv.height)
        on_cursor_row: root.change_scroll_y(ti, scrlv)

[brentpicasso]

+1 right now on a mobile device, it is impossible to scroll a TextInput with just the touch interface.

[misl6]

The issue have been fixed by @DexerBR via #7610