how to capture bluetooth command text selection running in QProcess ?

ChrisW67

There is no relationship between the QTextEdit, or whatever else you put in the QMdiSubWindow, and the separate operating system process you start (xterm) other than that you have directed that process to render its output on the screen in the same location as the QMdiSubWindow.

There is no relationship between the input/output streams of the xterm you have launched with QProcess and the input/output streams of the process or processes being run internally by xterm. So, for example, xterm does not send anything to standard out when it is asked, as you do, to execute bluetoothctl inside even though bluetoothctl does output (see example below).

You therefore cannot access the bluetoothctl output through the QProcess instance.

Here is a complete example widget that captures the output into a QTextEdit and can see the selections/clipboard.

#ifndef DEMOWIDGET_H
#define DEMOWIDGET_H

#include <QWidget>
#include <QTextEdit>
#include <QProcess>

class DemoWidget : public QWidget
{
    Q_OBJECT

public:
    DemoWidget(QWidget *parent = nullptr);
    ~DemoWidget();

private slots:
    void startProcess();
    void handleOutput();
    void finishedOutput();
    void handleSelection();

private:
    QTextEdit *m_textEdit;
    QTextEdit *m_selectedEdit;
    QProcess *m_process;
    QByteArray buffer;
};
#endif // DEMOWIDGET_H

#include "demowidget.h"

#include <QVBoxLayout>
#include <QTimer>
#include <QStandardPaths>
#include <QClipboard>
#include <QGuiApplication>

DemoWidget::DemoWidget(QWidget *parent)
    : QWidget(parent)
    , m_textEdit(nullptr)
    , m_selectedEdit(nullptr)
    , m_process(nullptr)
{
    m_textEdit = new QTextEdit(this);
    m_textEdit->setLineWrapMode(QTextEdit::NoWrap);
    m_textEdit->setAcceptRichText(false);
    m_textEdit->setReadOnly(true);
    connect(m_textEdit, &QTextEdit::selectionChanged, this, &DemoWidget::handleSelection);

    m_selectedEdit = new QTextEdit(this);
    m_selectedEdit->setLineWrapMode(QTextEdit::NoWrap);
    m_selectedEdit->setAcceptRichText(false);
    m_selectedEdit->setReadOnly(true);

    QVBoxLayout *layout = new QVBoxLayout(this);
    layout->addWidget(m_textEdit);
    layout->setStretchFactor(m_textEdit, 4);
    layout->addWidget(m_selectedEdit);
    layout->setStretchFactor(m_selectedEdit, 1);

    resize(1024, 768);

    QTimer::singleShot(1000, this, &DemoWidget::startProcess);
}

DemoWidget::~DemoWidget()
{
}

void DemoWidget::startProcess()
{
    m_process = new QProcess(this);
    connect(m_process, &QProcess::readyReadStandardOutput, this, &DemoWidget::handleOutput);
    connect(m_process, &QProcess::finished, this, &DemoWidget::finishedOutput);

    QStringList args = QStringList() << "-l" << QStandardPaths::standardLocations(QStandardPaths::HomeLocation).at(0);
    m_process->start("/usr/bin/ls", args);
}

void DemoWidget::handleOutput()
{
    QByteArray processOutput = m_process->readAllStandardOutput();
    m_textEdit->append(QString::fromUtf8(processOutput));
}

void DemoWidget::finishedOutput()
{
    m_textEdit->append(QStringLiteral("\n\n=====\nFinished"));
}

void DemoWidget::handleSelection()
{
    // will work on Linux only, rough demo only
    QClipboard *clipboard = QGuiApplication::clipboard();
    m_selectedEdit->setPlainText(clipboard->text(QClipboard::Selection));
}

No intervening xterm, no separate processes rendering into a Qt window, no problem accessing the text in the edit. This is a way to address what you are trying to do, but what you are trying to do is probably not the best solution to your actual problem... you could not make QBluetooth work.

This post proudly sponsored by XY Problem

JonB

@ChrisW67
We have already explained this to the OP. Back in September in https://forum.qt.io/topic/139374/another-xterm-qtextedit-issues/10 I took the time to write just what she needs for running the bluetoothctl, capturing its input/output, removing the ANSI "color" control sequences it emits, and displaying its output in a QTextEdit. It also shows a screenshot of what it looks like for a small exchange.
alt text

Because I wanted to be helpful. Obviously it's dead easy to add cut/copy/paste between such a QTextEdit and other windows if desired. Explained why using xterm is the wrong way to go. Asked her to just try it for herself so she could see. But was told

**PLEASE - If your know the answer post it... other contributions are superfluous at this point **

Anonymous_Banned275

@ChrisW67 Thanks.

After briefly reading you excellent post I still do not get how I can highlight specific text, using mouse, and not be able to detect that by any means - using OS or mouse (down) . If event ( highlight) happens there MUST be a way to detect it.

I went thru the MDI example code and found this line

CCC_MdiChild *CCC_MainWindow::createMdiChild()
{

    // insert  new child here ??
#ifdef TRACE_MDI_XTERM
    qDebug()<< "TRACE_MDI_XTERM  "  <<Q_FUNC_INFO;
    qDebug()<< "TRACE_MDI_XTERM  @line "  << QString::number(__LINE__);
    qDebug()<< "TRACE_MDI_XTERM insert  new child here ??  @line "  << QString::number(__LINE__);
#endif
    CCC_MdiChild *child = new CCC_MdiChild;
    mdiArea->addSubWindow(child);
    // ??
    here
#ifndef QT_NO_CLIPBOARD
    connect(child, &QTextEdit::copyAvailable, cutAct, &QAction::setEnabled);
    connect(child, &QTextEdit::copyAvailable, copyAct, &QAction::setEnabled);
#endif

    return child;
}

Since the code is poorly documented I have no clue what / how is this used .
I'll looking into it.

Anonymous_Banned275

I would like to concentrate on SPECIFIC problem - if possible.
It may or may not lead to problem solution.

I can detect mouse movement SIGNAL -after it enters the "Black frame".
I have a function to process "mouse down" but it never executes.
BUT if either mouse button is pressed - "mouse move" is NOT generated - hence the button(s) are acknowledged somehow.

HOWEVER - I am getting this run time message
"Selection too old..." and like to identify where it is coming from .

Christian Ehrlicher

@AnneRanch said in how to capture bluetooth command text selection running in QProcess ?:

I can detect mouse movement SIGNAL -after it enters the "Black frame".

For the nth time: the 'black frame' is another application where you don't have control of it.

Anonymous_Banned275

@ChrisW67 said in how to capture bluetooth command text selection running in QProcess ?:

Chis
I have your code partially inserted in my project.

Since your code runs the QProcess I have to bypass my "run QProcess" or add your code to existing MDI child.

So far it looks as it will process the text - the task is still to "drag and drop" the selected text between MDI subwindows .

I will tackle the graphics after I get this resolved - using QClipboard mode.

PS
I have explained (several times) I like to "drag and drop" using xterm/ bluetoothctl GUI - NOT just bluetoothctl text.
I had that - just text - working long time ago.

I am NOT changing my task / goal just because.....

There is no relationship between the QTextEdit, or whatever else you put in the QMdiSubWindow, and the separate operating system process you start (xterm) other than that you have directed that process to render its output on the screen in the same location as the QMdiSubWindow.

There is no relationship between the input/output streams of the xterm you have launched with QProcess and the input/output streams of the process or processes being run internally by xterm. So, for example, xterm does not send anything to standard out when it is asked, as you do, to execute bluetoothctl inside even though bluetoothctl does output (see example below).

You therefore cannot access the bluetoothctl output through the QProcess instance.

Here is a complete example widget that captures the output into a QTextEdit and can see the selections/clipboard.
#ifndef DEMOWIDGET_H
#define DEMOWIDGET_H

#include <QWidget>
#include <QTextEdit>
#include <QProcess>

class DemoWidget : public QWidget
{
    Q_OBJECT

public:
    DemoWidget(QWidget *parent = nullptr);
    ~DemoWidget();

private slots:
    void startProcess();
    void handleOutput();
    void finishedOutput();
    void handleSelection();

private:
    QTextEdit *m_textEdit;
    QTextEdit *m_selectedEdit;
    QProcess *m_process;
    QByteArray buffer;
};
#endif // DEMOWIDGET_H
#include "demowidget.h"

#include <QVBoxLayout>
#include <QTimer>
#include <QStandardPaths>
#include <QClipboard>
#include <QGuiApplication>

DemoWidget::DemoWidget(QWidget *parent)
    : QWidget(parent)
    , m_textEdit(nullptr)
    , m_selectedEdit(nullptr)
    , m_process(nullptr)
{
    m_textEdit = new QTextEdit(this);
    m_textEdit->setLineWrapMode(QTextEdit::NoWrap);
    m_textEdit->setAcceptRichText(false);
    m_textEdit->setReadOnly(true);
    connect(m_textEdit, &QTextEdit::selectionChanged, this, &DemoWidget::handleSelection);

    m_selectedEdit = new QTextEdit(this);
    m_selectedEdit->setLineWrapMode(QTextEdit::NoWrap);
    m_selectedEdit->setAcceptRichText(false);
    m_selectedEdit->setReadOnly(true);

    QVBoxLayout *layout = new QVBoxLayout(this);
    layout->addWidget(m_textEdit);
    layout->setStretchFactor(m_textEdit, 4);
    layout->addWidget(m_selectedEdit);
    layout->setStretchFactor(m_selectedEdit, 1);

    resize(1024, 768);

    QTimer::singleShot(1000, this, &DemoWidget::startProcess);
}

DemoWidget::~DemoWidget()
{
}

void DemoWidget::startProcess()
{
    m_process = new QProcess(this);
    connect(m_process, &QProcess::readyReadStandardOutput, this, &DemoWidget::handleOutput);
    connect(m_process, &QProcess::finished, this, &DemoWidget::finishedOutput);

    QStringList args = QStringList() << "-l" << QStandardPaths::standardLocations(QStandardPaths::HomeLocation).at(0);
    m_process->start("/usr/bin/ls", args);
}

void DemoWidget::handleOutput()
{
    QByteArray processOutput = m_process->readAllStandardOutput();
    m_textEdit->append(QString::fromUtf8(processOutput));
}

void DemoWidget::finishedOutput()
{
    m_textEdit->append(QStringLiteral("\n\n=====\nFinished"));
}

void DemoWidget::handleSelection()
{
    // will work on Linux only, rough demo only
    QClipboard *clipboard = QGuiApplication::clipboard();
    m_selectedEdit->setPlainText(clipboard->text(QClipboard::Selection));
}
No intervening xterm, no separate processes rendering into a Qt window, no problem accessing the text in the edit. This is a way to address what you are trying to do, but what you are trying to do is probably not the best solution to your actual problem... you could not make QBluetooth work.

This post proudly sponsored by XY Problem

Christian Ehrlicher

@AnneRanch said in how to capture bluetooth command text selection running in QProcess ?:

I have explained (several times) I like to "drag and drop" using xterm/ bluetoothctl GUI - NOT just bluetoothctl text.

And we told you that this does not work when the external process doesn't support it.

ChrisW67

@JonB I know. You can lead a horse to water but you cannot make it drink.

JonB

@AnneRanch said in how to capture bluetooth command text selection running in QProcess ?:

PS
I have explained (several times) I like to "drag and drop" using xterm/ bluetoothctl GUI - NOT just bluetoothctl text.
I had that - just text - working long time ago.
I am NOT changing my task / goal just because.....

I hear what you are saying. It's just that if you removed the xterm and did the bluetoothctl directly into a QTextEdit you would be able to easily do/recognise cut/copy/paste/drag/drop between that QTextEdit and your other windows in a way that won't be possible using xterm.

Anonymous_Banned275

UNTIL SOMEBODY BOTHERS TO READ And actually answers / elaborate on this thread original post - this is getting nowhere and very tiresome.

STUPID insults seldom lead to a solution... stop .

So ONE MORE TIME

What event / signal or whatever is generated when CLICKING ON SELECTED TEXT HIGHLIGHTS IT ?

Christian Ehrlicher

@AnneRanch said in how to capture bluetooth command text selection running in QProcess ?:

What event / signal or whatever is generated when CLICKING ON SELECTED TEXT HIGHLIGHTS IT ?

None in your application.

ChrisW67

@AnneRanch said in how to capture bluetooth command text selection running in QProcess ?:

What event / signal or whatever is generated when CLICKING ON SELECTED TEXT HIGHLIGHTS IT ?

Or, if you remove xterm as an intermediary, you can get the text in a Qt environment and receive QTextEdit::selectionChanged() and QTextEdit::copyAvailable() signals. This is demonstrated in my example widget.