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copied!<p>As @Inazfiger says, your objects need at least one strong (retaining) reference, otherwise they won't be retained.</p> <p>In this case, you're assigning the picker view to a <code>UITextField</code>'s <code>inputView</code> property. The text field will retain the picker view (I know this because the <code>inputView</code> property on <code>UITextField</code> is <a href="https://developer.apple.com/library/ios/#documentation/uikit/reference/UITextField_Class/Reference/UITextField.html#//apple_ref/occ/instp/UITextField/inputView" rel="noreferrer">declared with the modifiers "readwrite, <strong>retain</strong>"</a>), but <strong>only once you've made the assignment</strong>. So if you want to stick with a weak reference, you need to rearrange your code slightly - something like this:</p> <pre><code>// Declare a temporary UIPickerView reference. By default, this is // a strong reference - so tempPicker will be retained until this // variable goes out of scope. UIPickerView *tempPicker = [[UIPickerView alloc] initWithFrame:frame]; // Configure the picker tempPicker.delegate = self; tempPicker.dataSource = self; // Assign the picker view to the text field's inputView property. This // will increase the picker's retain count. Now it'll no longer be // released when tempPicker goes out of scope. textField.inputView = tempPicker; // Finally, assign the same object to self.levelPicker - it won't // go out of scope as long as it remains assigned to textField's // inputView property, and textField itself remains retained. self.levelPicker = tempPicker; </code></pre>

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