Event handling challenges

Hi Squeakers,
My SRE context browser is a tool for drawing a snapshot of a selected structure of interlinked objects where each object is shown as a rectangular symbol. This diagram shows an object with its class and superclass objects:


SRE has worked for years, last in 'Squeak3.10.2'. In 'Squeak5.3', the same program went into an infinite loop. It transpired that myClass>>processEvent: anEvent using: defaultDispatcher had become a new thing called an event filter and needed to return an Event or a Symbol. That problem fixed; the program still misbehaves. The problem seems to be with event handling. I have never been into that corner of Smalltalk but have read some Squeak documentation. I have not found any concrete code.  I realize that I will never understand Squeak's event handling by reading code, code comments, and even the documentation I have found. There has apparently been a significant increase in complexity lately. An example: In 3,10,2, class MorphicEventDispatcher has 4 methods. In 5,3, it has 16.

Here's the beginning of my challenges with 5.3: I find two anomalies in a diagram with just one symbol:

1.     When I move some other window to a position within the diagram, the diagram grabs it and makes it a submorph of itself.  In 3.10.2, the diagram ignores it.
2.     The cursor becomes a text cursor when I move the mouse across a symbol.

I have no explanation for either anomaly. My SRE code is a kludge and is almost unreadable. It is hard to formulate a question without the whole code as a background, and I have tried to reproduce them in a simple example. I managed to reproduce the first, but not the second anomaly. In a workspace, copy, select,  and do it. The XXX-symbol becomes attached to the cursor, and I place it in the blue background.

joe := PasteUpMorph new color: Color lightBlue.
joe bounds: (500@400 corner: 800@600).
joe dropEnabled: true.
joe openInWorld.
circle := CircleMorph new.
joe addMorphCentered: circle.
tex := TextMorphXX new
        contents: 'XXX';
        borderWidth: 1;
        color: Color red;
        extent: 100@100.
tex openInHand.

There is only one  method in class TextMorphXX (sco TextMorph):

processEvent: anEvent using: defaultDispatcher
    ^#rejected

I move some background window,  actually a collapsed Monticello thing, to Joe's position, Joe grabs it and makes it into a submorph. Any hints about how to proceed will be greatly appreciated.
--Trygve

--

The essence of object orientation is that objects collaborate  to achieve a goal.
Trygve Reenskaug      [hidden email]
Morgedalsvn. 5A       http://folk.uio.no/trygver/
N-0378 Oslo             http://fullOO.info
Norway                     Tel: (+47) 468 58 625

Not quite. Joe now throws the the strange Morph back to where it came from instead of ignoring it.
I need Joe to accept all TexMorphXX but ignore the rest.

PasteUpMorphXX>>acceptDroppingMorph: morphToDrop event: evt
    (morphToDrop isKindOf: TextMorphXX) ifFalse: [
        ^morphToDrop rejectDropMorphEvent: evt].

On 2020.06.15 15:13, karl ramberg wrote:

Hi,

When you open a morph for dropping it will accept all dropped morphs:

joe dropEnabled: true.

To filter what is accepted you must override acceptDroppingMorph: aMorph event: evt

Look at implementors for that method.

Best,

Karl

On Mon, Jun 15, 2020 at 2:44 PM Trygve Reenskaug <[hidden email]> wrote:

Hi Squeakers,
My SRE context browser is a tool for drawing a snapshot of a selected structure of interlinked objects where each object is shown as a rectangular symbol. This diagram shows an object with its class and superclass objects:


SRE has worked for years, last in 'Squeak3.10.2'. In 'Squeak5.3', the same program went into an infinite loop. It transpired that myClass>>processEvent: anEvent using: defaultDispatcher had become a new thing called an event filter and needed to return an Event or a Symbol. That problem fixed; the program still misbehaves. The problem seems to be with event handling. I have never been into that corner of Smalltalk but have read some Squeak documentation. I have not found any concrete code.  I realize that I will never understand Squeak's event handling by reading code, code comments, and even the documentation I have found. There has apparently been a significant increase in complexity lately. An example: In 3,10,2, class MorphicEventDispatcher has 4 methods. In 5,3, it has 16.

Here's the beginning of my challenges with 5.3: I find two anomalies in a diagram with just one symbol:

1.     When I move some other window to a position within the diagram, the diagram grabs it and makes it a submorph of itself.  In 3.10.2, the diagram ignores it.
2.     The cursor becomes a text cursor when I move the mouse across a symbol.

I have no explanation for either anomaly. My SRE code is a kludge and is almost unreadable. It is hard to formulate a question without the whole code as a background, and I have tried to reproduce them in a simple example. I managed to reproduce the first, but not the second anomaly. In a workspace, copy, select,  and do it. The XXX-symbol becomes attached to the cursor, and I place it in the blue background.

joe := PasteUpMorph new color: Color lightBlue.
joe bounds: (500@400 corner: 800@600).
joe dropEnabled: true.
joe openInWorld.
circle := CircleMorph new.
joe addMorphCentered: circle.
tex := TextMorphXX new
        contents: 'XXX';
        borderWidth: 1;
        color: Color red;
        extent: 100@100.
tex openInHand.

There is only one  method in class TextMorphXX (sco TextMorph):

processEvent: anEvent using: defaultDispatcher
    ^#rejected

I move some background window,  actually a collapsed Monticello thing, to Joe's position, Joe grabs it and makes it into a submorph. Any hints about how to proceed will be greatly appreciated.
--Trygve

--

The essence of object orientation is that objects collaborate  to achieve a goal.
Trygve Reenskaug      [hidden email]
Morgedalsvn. 5A       http://folk.uio.no/trygver/
N-0378 Oslo             http://fullOO.info
Norway                     Tel: (+47) 468 58 625

--

The essence of object orientation is that objects collaborate  to achieve a goal.
Trygve Reenskaug      [hidden email]
Morgedalsvn. 5A       http://folk.uio.no/trygver/
N-0378 Oslo             http://fullOO.info
Norway                     Tel: (+47) 468 58 625

Try this

PasteUpMorphXX>>acceptDroppingMorph: morphToDrop event: evt
    (morphToDrop isKindOf: TextMorphXX) ifFalse: [
        ^morphToDrop rejectDropMorphEvent: evt].

    super acceptDroppingMorph: aPiece event: evt.

Best,

Karl

On Mon, Jun 15, 2020 at 3:47 PM Trygve Reenskaug <[hidden email]> wrote:

Not quite. Joe now throws the the strange Morph back to where it came from instead of ignoring it.
I need Joe to accept all TexMorphXX but ignore the rest.

PasteUpMorphXX>>acceptDroppingMorph: morphToDrop event: evt
    (morphToDrop isKindOf: TextMorphXX) ifFalse: [
        ^morphToDrop rejectDropMorphEvent: evt].

On 2020.06.15 15:13, karl ramberg wrote:

Hi,

When you open a morph for dropping it will accept all dropped morphs:

joe dropEnabled: true.

To filter what is accepted you must override acceptDroppingMorph: aMorph event: evt

Look at implementors for that method.

Best,

Karl

On Mon, Jun 15, 2020 at 2:44 PM Trygve Reenskaug <[hidden email]> wrote:

Hi Squeakers,
My SRE context browser is a tool for drawing a snapshot of a selected structure of interlinked objects where each object is shown as a rectangular symbol. This diagram shows an object with its class and superclass objects:


SRE has worked for years, last in 'Squeak3.10.2'. In 'Squeak5.3', the same program went into an infinite loop. It transpired that myClass>>processEvent: anEvent using: defaultDispatcher had become a new thing called an event filter and needed to return an Event or a Symbol. That problem fixed; the program still misbehaves. The problem seems to be with event handling. I have never been into that corner of Smalltalk but have read some Squeak documentation. I have not found any concrete code.  I realize that I will never understand Squeak's event handling by reading code, code comments, and even the documentation I have found. There has apparently been a significant increase in complexity lately. An example: In 3,10,2, class MorphicEventDispatcher has 4 methods. In 5,3, it has 16.

Here's the beginning of my challenges with 5.3: I find two anomalies in a diagram with just one symbol:

1.     When I move some other window to a position within the diagram, the diagram grabs it and makes it a submorph of itself.  In 3.10.2, the diagram ignores it.
2.     The cursor becomes a text cursor when I move the mouse across a symbol.

I have no explanation for either anomaly. My SRE code is a kludge and is almost unreadable. It is hard to formulate a question without the whole code as a background, and I have tried to reproduce them in a simple example. I managed to reproduce the first, but not the second anomaly. In a workspace, copy, select,  and do it. The XXX-symbol becomes attached to the cursor, and I place it in the blue background.

joe := PasteUpMorph new color: Color lightBlue.
joe bounds: (500@400 corner: 800@600).
joe dropEnabled: true.
joe openInWorld.
circle := CircleMorph new.
joe addMorphCentered: circle.
tex := TextMorphXX new
        contents: 'XXX';
        borderWidth: 1;
        color: Color red;
        extent: 100@100.
tex openInHand.

There is only one  method in class TextMorphXX (sco TextMorph):

processEvent: anEvent using: defaultDispatcher
    ^#rejected

I move some background window,  actually a collapsed Monticello thing, to Joe's position, Joe grabs it and makes it into a submorph. Any hints about how to proceed will be greatly appreciated.
--Trygve

--

The essence of object orientation is that objects collaborate  to achieve a goal.
Trygve Reenskaug      [hidden email]
Morgedalsvn. 5A       http://folk.uio.no/trygver/
N-0378 Oslo             http://fullOO.info
Norway                     Tel: (+47) 468 58 625

--

The essence of object orientation is that objects collaborate  to achieve a goal.
Trygve Reenskaug      [hidden email]
Morgedalsvn. 5A       http://folk.uio.no/trygver/
N-0378 Oslo             http://fullOO.info
Norway                     Tel: (+47) 468 58 625

Hi Squeakers,
My SRE context browser is a tool for drawing a snapshot of a selected structure of interlinked objects where each object is shown as a rectangular symbol. This diagram shows an object with its class and superclass objects:


SRE has worked for years, last in 'Squeak3.10.2'. In 'Squeak5.3', the same program went into an infinite loop. It transpired that myClass>>processEvent: anEvent using: defaultDispatcher had become a new thing called an event filter and needed to return an Event or a Symbol. That problem fixed; the program still misbehaves. The problem seems to be with event handling. I have never been into that corner of Smalltalk but have read some Squeak documentation. I have not found any concrete code.  I realize that I will never understand Squeak's event handling by reading code, code comments, and even the documentation I have found. There has apparently been a significant increase in complexity lately. An example: In 3,10,2, class MorphicEventDispatcher has 4 methods. In 5,3, it has 16.

Here's the beginning of my challenges with 5.3: I find two anomalies in a diagram with just one symbol:

1.     When I move some other window to a position within the diagram, the diagram grabs it and makes it a submorph of itself.  In 3.10.2, the diagram ignores it.
2.     The cursor becomes a text cursor when I move the mouse across a symbol.

I have no explanation for either anomaly. My SRE code is a kludge and is almost unreadable. It is hard to formulate a question without the whole code as a background, and I have tried to reproduce them in a simple example. I managed to reproduce the first, but not the second anomaly. In a workspace, copy, select,  and do it. The XXX-symbol becomes attached to the cursor, and I place it in the blue background.

joe := PasteUpMorph new color: Color lightBlue.
joe bounds: (500@400 corner: 800@600).
joe dropEnabled: true.
joe openInWorld.
circle := CircleMorph new.
joe addMorphCentered: circle.
tex := TextMorphXX new
        contents: 'XXX';
        borderWidth: 1;
        color: Color red;
        extent: 100@100.
tex openInHand.

There is only one  method in class TextMorphXX (sco TextMorph):

processEvent: anEvent using: defaultDispatcher
    ^#rejected

I move some background window,  actually a collapsed Monticello thing, to Joe's position, Joe grabs it and makes it into a submorph. Any hints about how to proceed will be greatly appreciated.
--Trygve

--

The essence of object orientation is that objects collaborate  to achieve a goal.
Trygve Reenskaug      [hidden email]
Morgedalsvn. 5A       http://folk.uio.no/trygver/
N-0378 Oslo             http://fullOO.info
Norway                     Tel: (+47) 468 58 625