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When implementing Custom Patches, the developer has the option to perform self-operations on a subclass of QCPatch.

Table of contents

1 Pausing and Resuming Notifications 1.1 [self pauseNotifications]; 1.2 [self resumeNotifications]; 2 Creating and Deleting Input and Output Ports 2.1 [self createInputWithPortClass:portclass forKey:key attributes:0x0]; 2.2 [self deleteInputForKey:key]; 2.3 [self createOutputWithPortClass:portclass forKey:key attributes:0x0]; 2.4 [self deleteOutputForKey:key]; 3 Logging 3.1 [self logMessage:@"foo"]; 3.2 NSLog(@"foo");

Pausing and Resuming Notifications

[self pauseNotifications];

• Pause notifications before creating/deleting input/output ports.

[self resumeNotifications];

• Resume notifications after input/output port creation/deletion is complete.

Creating and Deleting Input and Output Ports

[self createInputWithPortClass:portclass forKey:key attributes:0x0];

• adds key to the input ports list

• portclass should be the "class" method of a class derived from QCPort. For example: [QCNumberPort class]
• key should be an arbitrary NSString, unique to this patch instance. For example: @"controller_0"
• attributes is possibly used to specify enum lists

[self deleteInputForKey:key];

• removes key from the input ports list

[self createOutputWithPortClass:portclass forKey:key attributes:0x0];

• adds key to the output ports list

• portclass should be the "class" method of a class derived from QCPort. For example: [QCNumberPort class]
• key should be an arbitrary NSString, unique to this patch instance. For example: @"controller_0"
• attributes is possibly used to specify enum lists

• Consumer patches (executionMode() == 1) cannot have output ports.

[self deleteOutputForKey:key];

• removes key from the output ports list

Logging

[self logMessage:@"foo"];

• Logs a message to the system console.
• Logs a message to the Viewer Log Drawer.
• Puts the patch in Debug mode.

NSLog(@"foo");

• Logs a message to the system console (without logging to the Viewer Log Drawer or putting the patch in Debug Mode.