QLineEdit in Android - no text visual

MartinGU

Qt 6.7.2, QtCreator 14.0.1, Linux Mint 22
Setup Android according to documentation
Create a new Android project, QtWidget Application.
Put a QLineEdit on mainwindow.ui
Run in Android Emulator or in physical phone (tested three different)

Type something into the QLineEdit, no text shown, something is entered but its like white text on white background. Changing color does not help!

Rotate screen and the text entered will be visible.

Is this just me or a horrible bug???

Morgatte

Yes, I believe it's a bug. It's not limited to a simple QLine. Regardless of the widget used, it's not updated on the upper half of the phone's screen. If you move it down to the lower part, you'll see that it works again.

This is a real issue, and I still don't have a solution...

To fix this bug, I use now Qt 6.8 but nothing has changed.

MartinGU

So this is how "well" they test the code before they release it...
Makes Qt more or less useless on Android.

Why try to report that some settings does not save in configuring an Android project when they cannot even handle widgets right...

And no better on 6.8 then?

@Morgatte said in QLineEdit in Android - no text visual:

Yes, I believe it's a bug. It's not limited to a simple QLine. Regardless of the widget used, it's not updated on the upper half of the phone's screen. If you move it down to the lower part, you'll see that it works again.

This is a real issue, and I still don't have a solution...

To fix this bug, I use now Qt 6.8 but nothing has changed.

mvuori

Qt can be usefull with Android. One just needs to pick a version that has the least number of serious bugs - and bugs that can be lived with. For some, it might still mean using a 5.x version...

Axel Spoerl

I fixed a bunch of bugs in the Android backing store and also in text edit fields. Haven’t come across this, but it absolutely sounds like a bug. Please boil it down to a simple reproducer that has no more than a few lines. Feel free to report a bug as well. I’ll look into it.

MartinGU

@Axel-Spoerl said in QLineEdit in Android - no text visual:

I fixed a bunch of bugs in the Android backing store and also in text edit fields. Haven’t come across this, but it absolutely sounds like a bug. Please boil it down to a simple reproducer that has no more than a few lines. Feel free to report a bug as well. I’ll look into it.

QTBUG-128794

Axel Spoerl

Please boil it down to a simple reproducer that has no more than a few lines.

The reproducer is missing in the ticket.
Please add an archive, that can be downloaded, compiled, deployed and run out of the box.

ademmler

Hi there,

I ran into the same/similar issue. Using Qt for Android 6.8.2, BulidTool 34, SDK 35.

I tried PlainTextEdit, LineEdit and TextEdit ... all have the same issue.
You need to type arround 20-30 Characters, after they start to appear ...
I took a photo to illustrate this. Any hint what to do?

After rotating the tablet, the letters are appearing.
QTextEdit::update does not help.
Is there a way to force textFiled or full screen update?

I also tried to use connect and update in the slot:

connect( textFiled, &QTextEdit::textChanged, this, &MyTalker::onTextChanged);
void MyTalker::onTextChanged()
{
    ui->textEdit->ensureCursorVisible();
    ui->textEdit->update();

    QApplication::processEvents();
}

ademmler

I found at least a workaround. I do a full update, each time the Text has changed.
For my small application this works. At least it is a workaround ...

void MyTalker::on_plainTextEdit_cursorPositionChanged() {
    this->update();
}

Maybe this is helpful for others with such issues ...