setChek and setPreviousStatement Details

Rainbow Market

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Jun 20, 2024, 1:28:44 PMJun 20

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Dear Team,

please help me for blocks "setCheck", "setPreviousStatement" and "setNextStatement" how to handle,

this is my code, i am try to do main block inside one by one sub_block 1 to 4 but it's not working.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Custom Blockly Blocks</title>

<script src="https://unpkg.com/blockly/blockly.min.js"></script>
<style>
body {
font-family: sans-serif;
}
#blocklyDiv {
height: 480px;
width: 600px;
}
</style>
</head>
<body>
<h1>Blockly Custom Blocks Example</h1>
<div id="blocklyDiv"></div>
<xml id="toolbox" style="display: none">
<block type="main_block"></block>
<block type="sub_block_1"></block>
<block type="sub_block_2"></block>
<block type="sub_block_3"></block>
<block type="sub_block_4"></block>
</xml>

<script>
Blockly.Blocks['main_block'] = {
init: function() {
this.appendDummyInput()
.appendField("main block");
this.appendStatementInput("NAME")
.setCheck("sub_block_1");
this.setColour(230);
this.setTooltip("");
this.setHelpUrl("");
}
};

Blockly.Blocks['sub_block_1'] = {
init: function() {
this.appendDummyInput()
.appendField("sub block 1");
this.appendStatementInput("NAME")
.setCheck(null);
this.setPreviousStatement(true, null);
this.setNextStatement(true, "sub_block_2");
this.setColour(230);
this.setTooltip("");
this.setHelpUrl("");
}
};

Blockly.Blocks['sub_block_2'] = {
init: function() {
this.appendDummyInput()
.appendField("sub block 2");
this.appendStatementInput("NAME")
.setCheck(null);
this.setPreviousStatement(true, "sub_block_1");
this.setNextStatement(true, "sub_block_3");
this.setColour(230);
this.setTooltip("");
this.setHelpUrl("");
}
};

Blockly.Blocks['sub_block_3'] = {
init: function() {
this.appendDummyInput()
.appendField("sub block 3");
this.appendStatementInput("NAME")
.setCheck(null);
this.setPreviousStatement(true, "sub_block_2");
this.setNextStatement(true, "sub_block_4");
this.setColour(230);
this.setTooltip("");
this.setHelpUrl("");
}
};

Blockly.Blocks['sub_block_4'] = {
init: function() {
this.appendDummyInput()
.appendField("sub block 4");
this.appendStatementInput("NAME")
.setCheck(null);
this.setPreviousStatement(true, "sub_block_3");
this.setNextStatement(true, null);
this.setColour(230);
this.setTooltip("");
this.setHelpUrl("");
}
};

// Initialize Blockly
const workspace = Blockly.inject('blocklyDiv', {
toolbox: document.getElementById('toolbox')
});
</script>
</body>
</html>

Regards,
Naveen S.

Mark Friedman

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Jun 20, 2024, 6:35:00 PMJun 20

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Naveen,

I am assuming that you want the various "sub" blocks to be allowed only in the order 1-4. Given that, I believe that the only thing that you are missing in your code is the specification of the connection type for sub_block_1 in its call to setPreviousStatement. You specified it correctly for the other sub-blocks.

Hope this helps.

-Mark

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Rainbow Market

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Jul 1, 2024, 1:43:54 PMJul 1

to Blockly

I understand your point, but I am not sure how to do it because I tried various processes to connect the substring, but I was still blocked. Please give me any sample code for this; that would be very helpful for the next process.

Thank and Regards,

Naveen S

Mark Friedman

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Jul 1, 2024, 3:54:15 PMJul 1

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Naveen,

The type checking mechanism can get a little confusing, and the particular case of statement inputs and their checks is not mentioned in depth in the documentation.

I believe that you need so to specify:

this.setPreviousStatement(true, "sub_block_1");

in you definition of sub_block_1, so that it matches this type check:

this.appendStatementInput("NAME")
.setCheck("sub_block_1");

specified in your main_block. I'll also point out that if you want to be consistent with the names of your other type checks you might want to replace "sub_block_1" with "main_block" in the two code fragments that I mentioned above.

Hope this helps.

-Mark

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